Item 16. Form 10-K Summary

None.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

			COSTAR GROUP, INC.
			By:			/s/ Andrew C. Florance
February 25, 2026						Andrew C. Florance
						President and Chief Executive Officer

KNOW ALL PERSONS BY THESE PRESENTS, that each individual whose signature appears below constitutes and appoints Andrew C. Florance and Christian M. Lown, and each of them individually, as their true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments to this report, and to file the same, with all exhibits thereto and to all documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he might or could do in person, herein by ratifying and confirming all that said attorneys-in-fact and agents or any of them, or his or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1934, as amended, this report has been signed by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

Signature						Capacity						Date
/s/ Louise S. Sams						Chairman of the Board of Directors						February 25, 2026
Louise S. Sams
/s/ Andrew C. Florance						Chief Executive Officer and						February 25, 2026
Andrew C. Florance						President and a Director
						(Principal Executive Officer)
/s/ Christian M. Lown						Chief Financial Officer						February 25, 2026
Christian M. Lown						(Principal Financial Officer)
/s/ Cynthia C. Cann						Chief Accounting Officer						February 25, 2026
Cynthia C. Cann						(Principal Accounting Officer)
/s/ John C. Berisford						Director						February 25, 2026
John C. Berisford
/s/ Angelique G. Brunner						Director						February 25, 2026
Angelique G. Brunner
/s/ Rachel C. Glaser						Director						February 25, 2026
Rachel C. Glaser
/s/ John W. Hill						Director						February 25, 2026
John W. Hill
/s/ Christine M. McCarthy						Director						February 25, 2026
Christine M. McCarthy
/s/ Robert W. Musslewhite						Director						February 25, 2026
Robert W. Musslewhite

COSTAR GROUP, INC.

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Reports of Independent Registered Public Accounting Firm (PCAOB ID Number 42)			F-2
Consolidated Statements of Operations			F-7
Consolidated Statements of Comprehensive Income			F-8
Consolidated Balance Sheets			F-9
Consolidated Statements of Changes in Stockholders’ Equity			F-10
Consolidated Statements of Cash Flows			F-11
Notes to Consolidated Financial Statements			F-12

F-1

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of CoStar Group, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of CoStar Group, Inc. (the Company) as of December 31, 2025 and 2024, the related consolidated statements of operations, comprehensive income, changes in stockholders’ equity and cash flows for each of the three years in the period ended December 31, 2025, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2025, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February 25, 2026 expressed an unqualified opinion thereon.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current period audit of the financial statements that were communicated or required to be communicated to the audit committee and that: (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

						Highly Automated Revenue Systems related to Subscription Revenue
Description of the Matter						As described in Note 2 to the consolidated financial statements, the Company derives revenues primarily by (i) providing access to its proprietary database of commercial real estate information and (ii) providing online marketplaces for professional property management companies, property owners, real estate agents and brokers and landlords, in each case, typically through a fixed fee for its subscription-based services. Revenues from subscription-based contracts are approximately 93% of total revenues for the current year and are recognized on a straight-line basis over the term of the agreement. The Company’s revenue recognition process involves several applications responsible for the initiation, processing, and recording of transactions. These applications interface with the Company’s enterprise resource planning system through automated and manual journal entries to accurately reflect revenue.

F-2

						The process to calculate, aggregate, and record revenue relies on multiple internally developed and external software programs and systems and involves interfacing significant volumes of data across the systems. Auditing the Company's accounting for revenue from subscription-based contracts was challenging and complex due to the high volume of individually-low-monetary-value transactions, dependency on the effective design and operation of multiple applications, some of which are specifically designed for the Company's business, and the use of multiple data sources in the revenue recognition process. Given the complexity of the information technology (IT) environment, the required involvement of professionals with expertise in IT to identify, test, and evaluate the revenue data flows, systems, and automated controls, we considered the audit of the Company’s subscription revenue-generating transactions to be a critical audit matter.
How We Addressed the Matter in Our Audit						We performed procedures related to the Company’s internal controls that included, among others, obtaining an understanding, evaluating the design, and testing the operating effectiveness of internal controls over the Company’s accounting for subscription revenue. We tested the controls over the initiation and billing of new and recurring subscriptions and the provisioning of customers. We tested the controls related to the key application interfaces between the provisioning, billing, and accounting systems and tested IT general controls related to access to the relevant applications and data, and changes made to the relevant systems, configurations and interfaces.
						We performed substantive audit procedures that included, among others, testing the Company’s accounting for revenue from contracts with customers, by testing, on a sample basis, the completeness and accuracy of the underlying data within the Company’s billing system.
						We performed data analytics by extracting data from the general ledger to evaluate the completeness and accuracy of recorded revenue and deferred revenue amounts, tracing a sample of sales transactions to source data, including evidence of cash receipt.
						Valuation of Certain Identified Intangible Assets Related to the Acquisitions of Matterport, LLC and Domain Holdings Australia Pty Limited
Description of the Matter						As discussed in Note 4 of the consolidated financial statements, during the year ended December 31, 2025, the Company completed the acquisitions of Matterport, LLC (“Matterport”) and Domain Holdings Australia Pty Limited (“Domain”) for an aggregate purchase price of approximately $3.9 billion. These transactions were accounted for as business combinations using the acquisition method of accounting, which requires, among other things, the identifiable assets acquired and liabilities assumed in the acquiree to be measured at their acquisition-date fair value. Any excess of the fair value of consideration transferred over the fair value of the identifiable assets acquired and liabilities assumed is recorded as goodwill.
						Auditing the Company’s accounting for its acquisitions of Matterport and Domain was complex due to the significant estimation uncertainty in the Company’s determination of the fair value of the identifiable intangible assets, which totaled $1.5 billion and consisted of customer relationships, developed technology, and trade name intangible assets. The Company used a discounted cash flow model to measure the customer relationship intangible assets and the relief from royalty approach to value the developed technology and trade name intangible assets. The significant assumptions used in the valuation of the intangible assets included discount rates, royalty rates, customer attrition rates, annual revenue growth rates, and EBITDA margin. These significant assumptions are forward looking and could be affected by future economic and market conditions.
How We Addressed the Matter in Our Audit						We obtained an understanding, evaluated the design, and tested the operating effectiveness of internal controls over the identification and valuation of the identified intangible assets including management’s review of the valuation models applied and significant underlying assumptions.

F-3

						To test the estimated fair value of the acquired intangible assets, we performed audit procedures that included, among others, evaluating the Company’s valuation methodologies used, evaluating the significant assumptions discussed above, and testing the completeness and accuracy of the underlying data supporting the significant assumptions. We involved our valuation specialists to assist in evaluating the methodology and certain significant assumptions used in the fair value estimates. For example, we compared the significant assumptions to current industry, market and economic trends as well as to historical results of the acquired business and to other guidelines used by companies within the same industry. In addition, we performed a sensitivity analysis on the significant assumptions to evaluate the change in the fair values of the intangible assets that would result from the changes in assumptions.

/s/ Ernst & Young LLP

We have served as the Company’s auditor since 1994.

Tysons, Virginia

February 25, 2026

F-4

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of CoStar Group, Inc.

Opinion on Internal Control Over Financial Reporting

We have audited CoStar Group, Inc.’s internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, CoStar Group, Inc. (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, 2025, based on the COSO criteria.

As indicated in the accompanying Management’s Report on Internal Control over Financial Reporting, management’s assessment of and conclusion on the effectiveness of internal control over financial reporting did not include the internal controls of Matterport, LLC and Domain Holdings Australia Pty Limited, which are included in the 2025 consolidated financial statements of the Company and collectively constituted less than 5% of total assets, excluding the preliminary value of goodwill and other intangible assets as of December 31, 2025, and less than 10% of total revenues for the year then ended. Our audit of internal control over financial reporting of the Company also did not include an evaluation of the internal control over financial reporting of Matterport, LLC and Domain Holdings Australia Pty Limited.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2025 and 2024, the related consolidated statements of operations, comprehensive income, changes in stockholders' equity and cash flows for each of the three years in the period ended December 31, 2025 and the related notes and our report dated February 25, 2026 expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

F-5

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

Tysons, Virginia

February 25, 2026

F-6

COSTAR GROUP, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(in millions, except per share data)

			Year Ended December 31,
			2025						2024						2023
Revenue			$	3,247					$	2,736					$	2,455
Cost of revenue			686						558						491
Gross profit			2,561						2,178						1,964
Operating expenses:
Selling and marketing (excluding customer base amortization)			1,560						1,364						990
Software development			406						326						268
General and administrative			549						439						382
Customer base amortization			118						44						42
			2,633						2,173						1,682
Income (loss) from operations			(72)						5						282
Interest income, net			110						213						214
Other income (expense), net			(8)						(8)						6
Income before income taxes			30						210						502
Income tax expense			23						71						127
Net income			$	7					$	139					$	375
Earnings per share — basic			$	0.02					$	0.34					$	0.92
Earnings per share — diluted			$	0.02					$	0.34					$	0.92
Weighted-average outstanding shares — basic			416.8						406.3						405.3
Weighted-average outstanding shares — diluted			420.7						407.8						406.9

See accompanying notes.

F-7

COSTAR GROUP, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(in millions)

						Year Ended December 31,
						2025						2024						2023
Net income						$	7					$	139					$	375
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment						106						(8)						12
Total other comprehensive income (loss), net of tax						106						(8)						12
Total comprehensive income						$	113					$	131					$	387

See accompanying notes.

F-8

COSTAR GROUP, INC.

CONSOLIDATED BALANCE SHEETS

(in millions, except per share data)

			December 31,
			2025						2024
ASSETS
Current assets:
Cash and cash equivalents			$	1,633					$	4,681
Restricted cash			100						—
Accounts receivable			263						211
Less: Allowance for credit losses			(29)						(23)
Accounts receivable, net			234						188
Income taxes receivable			18						—
Prepaid expenses and other current assets			134						81
Total current assets			2,119						4,950
Deferred income taxes, net			47						31
Property and equipment, net			1,323						1,015
Lease right-of-use assets			123						103
Goodwill			4,944						2,528
Intangible assets, net			1,771						433
Deferred commission costs, net			184						170
Deposits and other assets			27						27
Total assets			$	10,538					$	9,257
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Accounts payable			$	42					$	44
Accrued wages and commissions			145						133
Accrued expenses			203						164
Litigation accrual			99						—
Income taxes payable			1						23
Lease liabilities			28						32
Deferred revenue			205						137
Other current liabilities			23						19
Total current liabilities			746						552
Long-term debt, net			993						992
Deferred income taxes, net			238						8
Income taxes payable			27						25
Lease and other long-term liabilities			163						127
Total liabilities			2,167						1,704
Stockholders’ equity:
Preferred stock, $0.01 par value; 2.0 million shares authorized; zero outstanding			—						—
Common stock, $0.01 par value; 1.2 billion shares authorized at December 31, 2025 and 2024; and 425.0 million issued and 417.9 million outstanding as of December 31, 2025 and 409.5 million issued and outstanding as of December 31, 2024			4						4
Additional paid-in capital			6,410						5,232
Treasury stock, 7.1 million shares, cost basis at December 31, 2025			(510)						—
Accumulated other comprehensive income (loss)			80						(26)
Retained earnings			2,350						2,343
Stockholders' equity attributable to CoStar Group			8,334						7,553
Equity attributable to NCI			37						—
Total equity			8,371						7,553
Total liabilities and stockholders’ equity			$	10,538					$	9,257

See accompanying notes.

F-9

COSTAR GROUP, INC.

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

(in millions)

			Common Stock												Additional Paid-In Capital						Treasury Stock						Accumulated Other Comprehensive Income (Loss)						Retained Earnings						Stockholders’ Equity Attributable to CoStar Group						Equity Attributable to NCI						Total Equity
			Shares						Amount
Balance at January 1, 2023			406.7						$	4					$	5,065					$	—					$	(30)					$	1,829					$	6,868					$	—					$	6,868
Net income			—						—						—						—						—						375						375						—						375
Other comprehensive income			—						—						—						—						12						—						12						—						12
Exercise of stock options			0.4						—						8						—						—						—						8						—						8
Restricted stock grants			1.4						—						—						—						—						—						—						—						—
Restricted stock grants surrendered			(0.7)						—						(23)						—						—						—						(23)						—						(23)
Stock-based compensation expense			—						—						84						—						—						—						84						—						84
Management stock purchase plan			0.1						—						(3)						—						—						—						(3)						—						(3)
Employee stock purchase plan			0.2						—						17						—						—						—						17						—						17
Balance at December 31, 2023			408.1						4						5,148						—						(18)						2,204						7,338						—						7,338
Net income			—						—						—						—						—						139						139						—						139
Other comprehensive loss			—						—						—						—						(8)						—						(8)						—						(8)
Exercise of stock options			0.1						—						7						—						—						—						7						—						7
Restricted stock grants			1.7						—						—						—						—						—						—						—						—
Restricted stock grants surrendered			(0.7)						—						(28)						—						—						—						(28)						—						(28)
Stock-based compensation expense			—						—						87						—						—						—						87						—						87
Management stock purchase plan			0.1						—						(2)						—						—						—						(2)						—						(2)
Employee stock purchase plan			0.2						—						20						—						—						—						20						—						20
Balance at December 31, 2024			409.5						4						5,232						—						(26)						2,343						7,553						—						7,553
Net income			—						—						—						—						—						7						7						—						7
Domain Acquisition			—						—						—						—						—						—						—						39						39
Other comprehensive income			—						—						—						—						106						—						106						—						106
Change in NCI			—						—						—						—						—						—						—						2						2
Distributions to NCI			—						—						—						—						—						—						—						(4)						(4)
Exercise of stock options			0.7						—						6						—						—						—						6						—						6
Restricted stock grants			3.4						—						—						—						—						—						—						—						—
Restricted stock grants surrendered			(0.6)						—						(73)						—						—						—						(73)						—						(73)
Stock-based compensation expense			—						—						192						—						—						—						192						—						192
Management stock purchase plan			—						—						(2)						—						—						—						(2)						—						(2)
Employee stock purchase plan			0.3						—						20						—						—						—						20						—						20
Stock repurchases under stock repurchase programs (7.1 million shares)			(7.1)						—						10						(510)						—						—						(500)						—						(500)
Common stock issued for Matterport Acquisition			11.7						—						1,025						—						—						—						1,025						—						1,025
Balance at December 31, 2025			417.9						$	4					$	6,410					$	(510)					$	80					$	2,350					$	8,334					$	37					$	8,371

See accompanying notes.

F-10

COSTAR GROUP, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(in millions)

			Year Ended December 31,
			2025						2024						2023
Operating activities:
Net income			$	7					$	139					$	375
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization			263						147						108
Amortization of deferred commissions costs			141						117						95
Non-cash lease expense			30						33						30
Stock-based compensation expense			194						89						85
Deferred income taxes, net			36						(50)						(37)
Credit loss expense			32						36						35
Other operating activities, net			(5)						1						(2)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable			(28)						(30)						(67)
Prepaid expenses, other current assets and other assets			(21)						(8)						(17)
Deferred commissions			(152)						(120)						(120)
Accounts payable and other liabilities			(12)						44						34
Lease liabilities			(31)						(38)						(39)
Income taxes payable, net			(45)						22						11
Deferred revenue			21						11						(1)
Net cash provided by operating activities			430						393						490
Investing activities:
Proceeds from sale and settlement of investments and other assets			205						2						4
Purchases of property, equipment, and other assets for new campuses			(307)						(579)						(118)
Purchases of property, equipment, and other assets			(82)						(59)						(25)
Purchases of equity securities			(285)						—						—
Cash paid for acquisitions, net of cash acquired			(2,347)						(277)						(100)
Net cash used in investing activities			(2,816)						(913)						(239)
Financing activities:
Repurchase of restricted stock to satisfy tax withholding obligations			(75)						(30)						(26)
Stock repurchase			(500)						—						—
Proceeds from exercise of stock options and employee stock purchase plan			24						25						23
Other financing activities, net			(8)						(9)						(1)
Net cash used in financing activities			(559)						(14)						(4)
Effect of foreign currency exchange rates on cash, cash equivalents, and restricted cash			(3)						(1)						1
Net (decrease) increase in cash, cash equivalents, and restricted cash			(2,948)						(535)						248
Cash, cash equivalents, and restricted cash at the beginning of period			4,681						5,216						4,968
Cash, cash equivalents, and restricted cash at the end of period			$	1,733					$	4,681					$	5,216
Supplemental cash flow disclosures:
Interest paid			$	30					$	31					$	31
Income taxes paid			$	73					$	100					$	163
Supplemental non-cash investing and financing activities:
Consideration owed for acquisitions			$	—					$	1					$	8
Accrued capital expenditures and non-cash landlord incentives			$	74					$	64					$	29

See accompanying notes.

F-11

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. ORGANIZATION

CoStar Group (the "Company") is a leading global provider of real estate information, analytics, online marketplaces, and 3D digital twin technology. The Company has created and compiled a standardized platform of real estate information and analytics and online marketplaces where industry professionals, consumers of real estate, and the related business communities can continuously interact and facilitate transactions by efficiently accessing and exchanging accurate and standardized real estate-related information. The Company's service offerings span all property types, including office, residential, retail, industrial, multifamily, land, mixed-use, and hospitality. The Company's services are typically distributed to its customers under subscription-based agreements that generally renew automatically, and have a minimum term of one year. The Company operates within two operating segments which are Commercial Real Estate and Residential Real Estate.

The Company acquired OnTheMarket, Visual Lease, Matterport, and Domain in December 2023, November 2024, February 2025, and August 2025, respectively. See Note 4 for further discussion of these acquisitions.

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Accounting policies are consistent for each operating segment.

Principles of Consolidation

The consolidated financial statements include CoStar Group, Inc. and all entities in which we have a controlling financial interest. To determine whether such an interest exists, we assess whether the entity qualifies as a VIE.

We consolidate VIEs when we are the primary beneficiary. We are deemed the primary beneficiary of a VIE when we have both (a) the power to direct the activities of the VIE that most significantly impact its economic performance, and (b) the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE.

In determining whether we are the primary beneficiary, we consider various factors regarding the nature of our involvement with the VIE, including our economic interests, voting rights, authority to appoint or remove directors, and ability to authorize key decisions. We also analyze the VIE’s design, including its capital structure, cash flows, and classes of shares.

As part of the Domain Acquisition, the Company obtained ownership interests in the AOMs, which are considered VIEs for which the Company is the primary beneficiary. Domain introduced the AOMs to incentivize real estate agents to increase their use of Domain's depth products by allowing agents to share in a portion of Domain's earnings in return for placing premium, higher-value advertisements on the Domain platform. Domain provides corporate services to the VIEs under services agreements. In addition, CoStar has issued letters of support to the VIEs, committing to provide financial support in the event that the VIEs are unable to meet their liabilities independently.

See Note 4 for additional details regarding the Domain acquisition.

Recast of Certain Prior Period Information

During fourth quarter of 2025, the Company changed the composition of the Company's segments from geography-based to product-portfolio-based. This change aligns with the internal reporting used by the CODM for assessing performance and allocating resources. Prior period segment disclosures have been recast to conform to the current presentation, except where it was impracticable to do so. These changes primarily impacted Notes 3 and 13.

The recast of prior period information did not affect the consolidated balance sheets, consolidated statements of operations, or other consolidated financial statements.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to revenue recognition, allowance for credit losses, the useful

F-12

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

lives and recoverability of long-lived and intangible assets, goodwill impairment assessment, income taxes, accounting for business combinations, stock-based compensation, estimating the Company's incremental borrowing rate for its leases, the determination of stand-alone selling prices of various performance obligations, and contingencies, among others. The Company bases these estimates on historical and anticipated results, trends, and various other assumptions that it believes are reasonable, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenue and expenses. Actual results could differ from these estimates.

Revenue Recognition

Revenue is recognized upon transfer of control of promised products or services to customers in an amount that reflects the consideration we expect to receive in exchange for those products or services. We enter into contracts that can include various combinations of products and services, which are generally capable of being distinct and accounted for as separate performance obligations. Revenue is recognized net of allowances for refunds and returns and any taxes collected from customers, which are subsequently remitted to governmental authorities.

Nature of Products and Services

The Company derives revenue primarily by (i) providing access to its proprietary database of commercial real estate information, including benchmarking and analytics for the hospitality industry and analytics for lenders and (ii) providing online marketplaces for professional property management companies, property owners, real estate agents and brokers, and landlords, in each case, typically through a fixed monthly fee for its subscription-based advertising services. Other subscription-based services include (i) real estate and lease management solutions to commercial customers and real estate investors, (ii) access to applications to manage workflow for residential real estate agents, and (iii) access to its AI-powered spatial data platform to create high-fidelity and high-accuracy digital twins of physical spaces.

Subscription contract rates are generally based on the number of sites, number of users, organization size, the customer’s business focus, geography, the number of properties reported on or analyzed, the number and types of services to which a customer subscribes, the number of properties a customer advertises, the number of digital twins hosted, the number of transactions and average transaction size a broker or agent has closed, and the prominence and placement of a customer's advertised properties in the search results. The Company’s subscription-based license, advertising packages, and membership agreements generally renew automatically, and a majority have a term of at least one year. Revenue from our subscription-based contracts was approximately 93%, 96%, and 95% of total revenue for the years ended December 31, 2025, 2024, and 2023, respectively.

The Company also derives revenue from transaction-based services including: (i) providing premium listings for individual properties on our marketplaces, (ii) providing data capture services to create digital twins, (iii) the sale of Matterport cameras and capture equipment, (iv) Ten-X's auctions, and (v) ancillary products and services that are sold on an ad hoc basis.

The Company analyzes contracts to determine the appropriate revenue recognition using the following steps: (i) identification of contracts with customers, (ii) identification of distinct performance obligations in the contract, (iii) determination of contract transaction price, (iv) allocation of contract transaction price to the performance obligations, and (v) determination of revenue recognition based on timing of satisfaction of the performance obligations.

The Company recognizes revenue upon the satisfaction of its performance obligations (upon transfer of control of promised services to its customers) in an amount that reflects the consideration to which it expects to be entitled to in exchange for those services. Revenue from subscription-based services is recognized on a straight-line basis over the term of the agreement. Revenue from premium listings sold on a transactional basis is recognized over the estimated period the advertisements will be active. Revenue from all other transaction-based services is recognized when the promised product or services are delivered, which, in the case of property auctions, is at the time of a successful closing of the sale of the auctioned property. Revenue from product sales is recognized upon control transferring to the customers, which is generally upon shipment. Revenue for sales of Matterport cameras are recorded net of estimates of returns, as buyers are entitled to return the camera within 30 days from the date of purchase for a full refund. These rights are accounted for as variable consideration and recognized as a reduction to the revenue recognized.

In limited circumstances, the Company's contracts with customers include promises to transfer multiple services, such as contracts for its subscription-based services and professional services or product sales, digital twin capture services, and subscription-based hosting service. For these contracts, the Company accounts for individual performance obligations separately if they are distinct, which involves the determination of the standalone selling price for each distinct performance obligation.

F-13

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Contract Balances and Other Receivables

Deferred revenue results from amounts billed in advance to customers or cash received from customers in advance of the Company's fulfillment of its performance obligations and is recognized as those obligations are satisfied.

Contract assets represent a conditional right to consideration for satisfied performance obligations that become a receivable when the conditions are satisfied. Contract assets are generated when contractual billing schedules differ from revenue recognition timing.

Assets Recognized from Costs to Obtain a Contract with a Customer

Certain sales commissions are considered incremental and recoverable costs of obtaining a contract with a customer. Sales commissions incurred for obtaining new contracts are deferred and then amortized as selling and marketing expenses (excluding customer base amortization) over a period of benefit that the Company has determined to be three years. The amortization periods were determined based on several factors, including the nature of the technology and proprietary data underlying the services being purchased, customer contract renewal rates, and industry competition. Sales commissions that do not represent incremental costs of obtaining a contract, or that would otherwise be amortized over a period of one year or less, are not subject to capitalization.

See Note 3 for further discussion of the Company's revenue recognition.

Cost of Revenue

Cost of revenue principally consists of salaries, benefits, bonuses, stock-based compensation expenses, and other indirect costs for the Company's researchers who collect and analyze the real estate data that is the basis for the Company's information, analytics, and online marketplace services and for employees that support these products. Additionally, cost of revenue includes amortization of acquired trade names, technology, and certain other intangible assets; product hosting costs; credit card and other transaction fees relating to processing customer transactions; cost of data from third-party data sources; costs of capture services; and costs of Matterport cameras sold.

Foreign Currency Translation

The Company’s reporting currency is the U.S. dollar. The functional currency for the majority of its operations is the local currency, with the exception of certain international locations for which the functional currency is the British Pound or U.S. dollar. Assets and liabilities denominated in a foreign currency are translated into U.S. dollars using the exchange rates in effect as of the balance sheet date. Gains and losses resulting from translation are included in accumulated other comprehensive income (loss). Currency gains and losses on the translation of intercompany loans made to foreign subsidiaries that are of a long-term investment nature are also included in accumulated other comprehensive income (loss). Gains and losses resulting from transactions denominated in a currency other than the functional currency of the entity are included in other income (expense), net in the consolidated statements of operations using the average exchange rates in effect during the period. The Company recognized a net foreign currency loss of $6 million, a net foreign currency loss of $1 million, and a net foreign currency gain of $3 million for the years ended December 31, 2025, 2024, and 2023, respectively, which are included in other income (expense), net on the consolidated statements of operations.

Accumulated Other Comprehensive Income (Loss)

The components of accumulated other comprehensive income (loss) were as follows (in millions):

			As of December 31,
			2025						2024
Foreign currency translation income (loss)			$	80					$	(26)
Total accumulated other comprehensive income (loss)			$	80					$	(26)

There were no amounts reclassified out of accumulated other comprehensive income (loss) to the consolidated statements of operations for both the years ended December 31, 2025 and 2024.

F-14

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Advertising Costs

The Company expenses advertising costs as incurred. Advertising costs include digital marketing, television, radio, print, and other media advertising. Advertising costs were $830 million, $845 million, and $550 million for the years ended December 31, 2025, 2024, and 2023, respectively.

Research and Development Costs

Research and development costs are expensed as incurred and consist primarily of salaries, consulting services, and other direct expenses.

Earnings Per Share

Earnings per share is computed by dividing net income by the weighted-average number of common shares outstanding during the period on a basic and diluted basis. The Company's potentially dilutive securities include outstanding stock options, and unvested stock-based awards, which include restricted stock awards that vest over a specific service period, restricted stock awards with a performance condition, restricted stock awards with a performance condition and a market condition, restricted stock units, and Matching RSUs awarded under the MSPP. Shares underlying unvested restricted stock awards that vest based on a performance condition and those that vest based on a performance and market condition that have not been achieved as of the end of the period are not included in the computation of basic or diluted earnings per share. Diluted earnings per share considers the impact of potentially dilutive securities except when the inclusion of the potentially dilutive securities would have an anti-dilutive effect.

See Note 15 for further discussion of the Company's calculation of earnings per share.

Stock-Based Compensation

Equity instruments issued in exchange for services performed by officers, employees, and directors of the Company are accounted for using a fair-value based method and the fair value of such equity instruments is recognized as expense in the consolidated statements of operations.

For stock-based awards that vest over a specific service period, compensation expense is measured based on the fair value of the awards at the grant date and is recognized on a straight-line basis over the service period of the awards, net of an estimated forfeiture rate. For equity instruments that vest based on achievement of a performance condition or both a performance and a market condition, stock-based compensation expense is recognized over the service period of the awards based on the expected achievement of the related performance conditions at the end of each reporting period. If the Company's initial estimates of the achievement of the performance conditions change, the related stock-based compensation expense may fluctuate from period to period based on those estimates. If the performance conditions are not met, no stock-based compensation expense will be recognized and any previously recognized stock-based compensation expense will be reversed. For awards with both a performance and a market condition, the Company estimates the fair value of each equity instrument granted on the date of grant using a Monte-Carlo simulation model. This pricing model uses multiple simulations to evaluate the probability of achieving the market condition to calculate the fair value of the awards which includes the recent market price and volatility of the Company's shares. When determining the grant date fair value of all stock-based awards, the Company considers whether it is in possession of any material, non-public information that upon its release would have a material effect on its share price, and if so, whether the observable share price or expected volatility assumptions used in determining the fair value of the awards should be adjusted.

Stock-based compensation expense for stock options, restricted stock awards, and restricted stock units issued under equity incentive plans, stock purchases under the ESPP, and DSUs and Matching RSUs awarded under the MSPP included in the Company’s consolidated statements of operations were as follows (in millions):

			Year Ended December 31,
			2025						2024						2023
Cost of revenue			$	21					$	14					$	14
Selling and marketing (excluding customer base amortization)			32						11						9
Software development			46						22						18
General and administrative			95						42						44
Total stock-based compensation expense			$	194					$	89					$	85

F-15

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Income Taxes

Deferred income taxes result from temporary differences between the tax basis of assets and liabilities and the basis reported in the Company’s consolidated financial statements. Deferred tax liabilities and assets are determined based on the difference between the financial statement and the tax basis of assets and liabilities using enacted rates in effect during the year in which the Company expects differences to reverse. Valuation allowances are provided against assets, including net operating losses, if the Company determines it is more likely than not that some portion or all of an asset may not be realized. Interest and penalties related to income tax matters are recognized in income tax expense.

The Company has elected to record the GILTI under the current-period cost method.

On July 4, 2025, new federal tax legislation, H.R.1, was enacted. The relevant effects of this legislation include making 100 percent bonus depreciation permanent, the permanent restoration of the ability of taxpayers to immediately expense certain domestic research and experimental expenditures, and the restoration of EBITDA-based interest deduction limitations. In addition, H.R.1 includes international tax provisions, including eliminating the net deemed tangible income return, decreasing the tax rates and taxable income computations applicable to GILTI and FDII, and permanently increasing the BEAT rate. Upon enactment in the third quarter of 2025, the legislation (i) did not materially impact our effective tax rate, (ii) decreased our cash income tax liability and (iii) increased our deferred tax liability. We continue to evaluate the provisions of the legislation and its potential effects on our consolidated balance sheets, consolidated statements of operations, and consolidated statements of cash flows, and disclosures addressing any material financial statement impact will be provided in future periods as the impact of the legislation is determined.

See Note 11 for further discussion of the Company's accounting for income taxes.

Loss Contingencies and Litigation Expense

The Company is subject to the possibility of losses from various contingencies, including certain legal proceedings. Significant judgment is necessary to estimate the probability and amount of a loss, if any, from such contingencies. An accrual is made when it is probable that a liability has been incurred or an asset has been impaired, and the amount of loss can be reasonably estimated. In accounting for the resolution of contingencies, significant judgment may be necessary to estimate amounts pertaining to periods prior to the resolution that are charged to operations in the period of resolution and amounts related to future periods. If only a range of estimated losses can be determined, the Company records an amount within the range that, in its judgment, reflects the most likely outcome; if none of the estimates within that range are a better estimate than any other amount, the Company records the low end of the range. Any such accrual would be charged to expense in the appropriate period.

Deal-Contingent Foreign Currency Forward Contracts

On May 9, 2025, the Company entered into deal-contingent foreign currency forward contracts to manage the risk of appreciation of the Australian dollar-denominated purchase price related to the Domain Transaction. Deal-contingent foreign currency forward contracts had an aggregate notional amount of A$2.4 billion ($1.5 billion). These derivative instruments were entered into as economic hedges and do not qualify for hedge accounting. The contracts were settled on August 22, 2025. The Company recognized a loss of $10 million for the year ended December 31, 2025 related to these contracts. The losses were recorded in other income (expense), net, in the consolidated statements of operations.

See Note 4 for further discussion regarding the Company's acquisitions.

Cash, Cash Equivalents, and Restricted Cash

The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Restricted cash consists of cash deposited as collateral related to a litigation bond in a third-party insured account. See Note 12 for further discussion regarding the Company's litigation.

F-16

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Cash, cash equivalents, and restricted cash are included in the following line items in the consolidated balance sheets and consolidated statements of cash flows (in millions):

			December 31, 2025						December 31, 2024
Cash and cash equivalents			$	1,633					$	4,681
Restricted cash			100						—
Total cash, cash equivalents, and restricted cash			$	1,733					$	4,681

Concentration of Credit Risk and Financial Instruments

The Company’s customer base creates a lack of dependence on any individual customer that mitigates the risk of nonpayment of the Company’s accounts receivable. No single customer accounted for more than 5% of the Company’s revenue for each of the years ended December 31, 2025, 2024, and 2023. The carrying amount of the accounts receivable approximates the net realizable value.

The Company holds cash at major financial institutions that often exceed Federal Deposit Insurance Corporation-insured limits. The Company manages its credit risk associated with cash concentrations by diversifying cash holdings across AAA-rated Government and Treasury Money Market Funds and multiple high quality financial institutions, and by periodically evaluating the credit quality of the primary financial institutions holding such deposits. The carrying value of cash approximates fair value. Historically, the Company has not experienced any losses due to such cash concentrations.

Allowance for Credit Losses

The Company maintains an allowance for credit losses to cover its current expected credit losses on its trade receivables and contract assets arising from the failure of customers to make contractual payments. The Company estimates credit losses expected over the life of its trade receivables and contract assets based on historical information combined with current conditions that may affect a customer’s ability to pay and reasonable and supportable forecasts. While the Company uses various credit quality metrics, it primarily monitors collectability by reviewing the duration of collection pursuits on its delinquent trade receivables and historical write-off trends. Based on the Company’s experience, the customer's delinquency status, which is analyzed periodically, is the strongest indicator of the credit quality of the underlying trade receivables. The Company’s policy is to write-off trade receivables when they are deemed uncollectible.

The following table details the activity related to the allowance for credit losses for trade receivables (in millions):

			Year Ended December 31,
			2025						2024						2023
Beginning balance			$	23					$	23					$	12
Current-period provision for expected credit losses			32						36						35
Write-offs charged against the allowance			(26)						(36)						(24)
Ending balance			$	29					$	23					$	23

Inventories

Inventories consist primarily of finished goods, assemblies, and raw materials. Assemblies are generally purchased from contract manufacturers. Inventories are valued at the lower of cost or net realizable value. Costs are determined using standard cost, which approximates actual cost on a first-in, first-out basis. The Company assesses the valuation of inventory and periodically adjusts the value for estimated excess and obsolete inventory based upon estimates of future demand and market conditions, as well as damaged or otherwise impaired goods.

F-17

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Inventories related to the Matterport Acquisition as of December 31, 2025 consisted of the following (in millions):

			December 31, 2025
Finished goods			$	4
Purchased parts and raw materials			2
Total inventories			$	6

Leases

The determination of whether an arrangement contains a lease and the classification of a lease, if applicable, is made at the commencement of the arrangement, at which time the Company also measures and recognizes a ROU asset, representing the Company’s right to use the underlying asset, and a lease liability, representing the Company’s obligation to make lease payments under the terms of the arrangement. For the purposes of recognizing ROU assets and lease liabilities associated with the Company’s leases, the Company has elected the practical expedient to not recognize a ROU asset or lease liability for short-term leases, which are leases with a term of 12 months or less. The lease term is defined as the noncancellable portion of the lease term, plus any periods covered by an option to extend the lease if it is reasonably certain that the option will be exercised.

In determining the amount of lease payments used in measuring ROU assets and lease liabilities, the Company has elected the practical expedient not to separate non-lease components from lease components for all classes of underlying assets. Consideration deemed part of the lease payments used to measure ROU assets and lease liabilities generally includes fixed payments and variable payments based on either an index or a rate, offset by lease incentives. Upon commencement, the initial ROU asset also includes any lease prepayments. ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. The rates implicit within the Company's leases are generally not determinable. Therefore, the Company's incremental borrowing rate is used to determine the present value of lease payments. The determination of the Company’s incremental borrowing rate requires judgment and is determined at lease commencement and is subsequently reassessed upon a modification to the lease arrangement.

Lease costs related to the Company's operating leases are generally recognized as a single ratable lease cost over the lease term.

See Note 6 for further discussion of the Company’s accounting for leases.

Property and Equipment, Net

Property and equipment are stated at cost, net of accumulated depreciation and amortization. All repairs and maintenance costs are expensed as incurred. Construction in progress includes expenditures for construction and improvements to our campuses and are stated at cost. Costs related to acquisition of additional aircraft components or the replacement of existing aircraft components are capitalized and depreciated over the estimated useful life of the aircraft or the added or replaced component, whichever is less. Depreciation and amortization are calculated on a straight-line basis over the following estimated useful lives of the assets:

Buildings						Twenty to thirty-nine years
Land						Indefinite
Aircraft						Ten to twenty years
Furniture and office equipment						Five to ten years
Vehicles						Four to five years
Computer hardware and software						Three to five years
Leasehold improvements						Shorter of lease terms or useful life

Qualifying internal-use software costs incurred during the application development stage, which consist primarily of internal product development costs, are capitalized and amortized over the estimated useful life of the asset. All other costs are expensed as incurred. The Company removes fully depreciated property and equipment from the cost and accumulated depreciation amounts disclosed in the period they become fully depreciated.

F-18

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Long-Lived Assets, Intangible Assets, and Goodwill

Long-lived assets, such as property and equipment, and purchased intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset or asset group. If the carrying amount of an asset exceeds its estimated undiscounted future cash flows, an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds the fair value of the asset. The Company capitalizes interest costs during the construction phase. Capitalized interest is added to the cost of the underlying asset upon substantial completion and amortized over the estimated useful life of the asset.

Acquired technology and data, customer base assets, trade names, and other intangible assets are related to the Company’s acquisitions. Acquired technology and data is amortized on a straight-line basis over periods ranging from 2 years to 10 years. Acquired intangible assets characterized as customer base assets consist of acquired customer contracts and the related customer relationships and are amortized over periods ranging from 5 years to 20 years. Acquired customer bases are amortized on an accelerated or straight-line basis depending on the expected economic benefit of the intangible asset. Acquired trade names and other intangible assets are amortized on a straight-line basis over periods ranging from 2 years to 15 years. The Company removes fully amortized intangible assets from the cost and accumulated amortization amounts disclosed.

The Company allocates goodwill to reporting units based on the reporting unit expected to benefit from the business combination. A reporting unit is defined as an operating segment or one level below an operating segment. We evaluate our reporting units on an annual basis and, if necessary, reassign goodwill using a relative fair value allocation approach. Goodwill is tested for impairment at least annually, on October 1, or more frequently if an event or other circumstance indicates that the fair value of a reporting unit may be below its carrying amount. The Company may first assess qualitative factors to evaluate whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount, or elect to bypass the qualitative assessment. If it is determined that it is more likely than not that the fair value of a reporting unit is less than its carrying value, or the Company elects to bypass the qualitative assessment, the Company then performs a quantitative assessment by determining the fair value of each reporting unit. The estimate of the fair value of each reporting unit is based on a projected discounted cash flow model that includes significant assumptions and estimates including the discount rate, growth rate and future financial performance. Assumptions about the discount rate are based on a weighted average cost of capital for comparable companies. Assumptions about the growth rate and future financial performance of a reporting unit are based on the Company's forecasts, business plans, economic projections, and anticipated future cash flows. The fair value of each reporting unit is compared to the carrying amount of the reporting unit. If the carrying value of the reporting unit exceeds the fair value, then an impairment loss is recognized for the difference.

See Notes 4, 8, and 9 for further discussion of the Company's acquisitions, goodwill, and intangible assets, respectively.

Leasing Operations and Other Expense/Income, Net

In February 2024, the Company closed on the purchase of an office tower and the land on which it rests in Arlington, Virginia. In January 2025, the Company relocated its headquarters from Washington, D.C. to Arlington, VA occupying approximately 30% of the building. The Company has and intends to continue to build out further space in this building to support anticipated growth and expansion of its operations in the coming years. As of December 31, 2025, the Company occupied approximately 50% of the property with the remainder leased or available to be leased to third parties. Maintenance, physical facilities, leasing, property management, and other key responsibilities related to property ownership are outsourced to professional real-estate managers. The office tower measures approximately 550,000 rentable square feet.

The Company accounted for the purchase of this building as an asset acquisition at the cost to acquire, including transaction costs. The Company estimated the fair values of acquired tangible assets (consisting of land, buildings, improvements, and other assets), identified intangible assets and liabilities (consisting of in-place leases and above- and below-market leases), and other liabilities based on its evaluation of information and estimates available at the date of acquisition. Based on these estimates, the Company allocated the total cost to the identified assets acquired and liabilities assumed based on their relative fair value.

The fair value of the building and building improvements consists of the physical structure containing rentable area, as well as amenities such as parking structures, and was valued as if vacant, using the cost approach, which uses replacement cost data obtained from industry recognized guides less depreciation as an input to estimate the fair value, with consideration given to its age, functionality, use classification, construction quality, replacement cost new, and accumulated depreciation (effective age vs. economic life). The Company also considered the value of the building using an income approach. The income approach

F-19

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

uses market leasing assumptions to estimate the fair value of the property as if vacant assuming lease-up at prevailing market rental rates over a market-based lease-up period, including deductions for lost-rent during lease-up and leasing costs. The cost and income approaches are reconciled to arrive at an estimated building fair value. The Company assessed the fair value of land based on market comparisons.

The fair values of identified intangible assets and liabilities were determined based on the following:

• The value allocable to the above- or below-market component of an acquired in-place lease is determined based upon the present value (using a discount rate that reflects the risks associated with the acquired lease) of the difference between: (i) the contractual amounts to be received pursuant to the lease over its remaining term and (ii) management's estimate of the amounts that would be received using market rates current at the time of the acquisition for the remaining term of the lease. Amounts allocated to above-market leases are recorded as above-market leases in intangible assets, net in the consolidated balance sheets. These intangible assets are amortized on a straight-line basis as a component of leasing operations to other income (expense), net in the consolidated statements of operations over the remaining terms of the respective leases.

• Factors considered in determining the value allocable to in-place leases during hypothetical lease-up periods related to space that is leased at the time of acquisition include: (i) lost rent and operating cost recoveries during the hypothetical lease-up period and (ii) theoretical leasing commissions required to execute similar leases. These intangible assets are recorded as in-place leases in intangible assets, net in the consolidated balance sheets and are amortized to other income (expense), net in the consolidated statements of operations over the remaining terms of the existing leases.

The total cost of the land and building was $343 million and was allocated to the following components (in millions):

Component			Balance Sheet Caption			Amount
Land			Property and equipment, net			$	17
Building			Property and equipment, net			224
Land and building improvements			Property and equipment, net			28
Above-market leases			Intangible assets, net			42
In-place leases			Intangible assets, net			32
						$	343

The cash paid for this asset acquisition was included in the caption purchases of property, equipment, and other assets for new campuses in the consolidated statement of cash flows. The Company records the third-party rental activity from this building's operations and leases, including building depreciation and operating expenses for space occupied by tenants, as other income (expense), net in the consolidated statements of operations.

In October 2024, the Company and a building tenant modified a lease agreement to reduce the leased space and extend the lease term of a portion of the remaining space. Among other provisions, the modified lease agreement required the tenant to make a $48 million buyout payment, in two equal installments which were received in the fourth quarter of 2024 and the second quarter in 2025. The buyout payments are recognized in other income (expense), net in the consolidated statements of operations ratably over the modified lease term. The tenant surrendered certain space concurrently with the execution of the modified lease agreement and the Company has outfit this space to host its employees.

Deferred lease income as of December 31, 2025 and December 31, 2024 was as follows (in millions):

Balance			Balance Sheet Caption			December 31, 2025						December 31, 2024
Current portion			Other current liabilities			$	6					$	5
Non-current portion			Lease and other long-term liabilities			35						18
Total deferred lease income						$	41					$	23

Lease income includes base rent each tenant pays in accordance with the terms of its respective lease and is reported on a straight-line basis over the non-cancellable term of the lease, which includes the effects of periodic step-ups in rent and rent abatements under the lease. When a renewal option is included within the lease, the Company assesses whether the option is reasonably certain of being exercised against relevant economic factors to determine whether the option period should be

F-20

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

included as part of the lease term. Further, lease income includes tenant reimbursement amounts for the recovery of the operating expenses and real estate taxes. Tenant reimbursements, which vary each period, are non-lease components that are not the predominant activity within the contract. The Company has elected the practical expedient that allows it to combine certain lease and non-lease components of operating leases. Non-lease components are recognized together with fixed base rent in “lease income,” as variable lease income in the same period as the related expenses are incurred. Variable lease income was not material for the years ended December 31, 2025 and December 31, 2024. Components of other income (expense), net related to leasing operations for the years ended December 31, 2025 and December 31, 2024 were as follows (in millions):

			Year Ended December 31,
			2025						2024
Lease income(1)			$	17					$	22
Less:
Property operating expenses			6						9
Depreciation and amortization expense			17						19
Other expense from leasing operations			$	(6)					$	(6)
__________________________
(1) Includes $4 million and $10 million of amortization expense of above-market leases for the years ended December 31, 2025 and December 31, 2024, respectively.

The following is a maturity analysis of the annual undiscounted cash flows of operating lease payments to be received as of December 31, 2025 (in millions):

			Operating Leases
2026			$	11
2027			13
2028			9
2029			8
2030			7
Thereafter			26
Total undiscounted cash flows			$	74

Building depreciation and operating expenses for space occupied by the Company are allocated between cost of revenue, selling and marketing (excluding customer base amortization), software development, and general and administrative expenses on the consolidated statement of operations based on the headcount of the respective departments occupying the building.

Debt Issuance Costs

Costs incurred in connection with the issuance of long-term debt are deferred and amortized as interest expense over the term of the related debt using the effective interest method for term debt and on a straight-line basis for revolving debt. The Company made a policy election to classify deferred issuance costs on the revolving credit facility as a long-term asset on its consolidated balance sheets. Upon a refinancing or amendment, previously capitalized debt issuance costs are expensed and included in loss on extinguishment of debt if the Company determines that there has been a substantial modification of the related debt. If the Company determines that there has not been a substantial modification of the related debt, any previously capitalized debt issuance costs are amortized as interest expense over the term of the new debt instrument.

See Note 10 for further discussion of the Company's accounting for its outstanding debt, revolving credit facility, and related issuance costs.

Business Combinations

The Company includes the results of operations of the businesses that it acquires from the date of acquisition. The Company generally allocates the purchase consideration to the tangible assets acquired and liabilities assumed and intangible assets acquired based on their estimated fair values on the date of the acquisition. The purchase price is generally determined based on the fair value of the assets transferred, liabilities assumed, and equity interests issued, after considering any transactions that are separate from the business combination. The excess of the fair value of purchase consideration, the fair

F-21

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

value of any NCI in the acquiree and the fair value of any previous equity interest in the acquiree over the fair values of these identifiable assets and liabilities is recorded as goodwill. In a business combination achieved in stages, the Company shall remeasure its previously held equity interest in the acquiree at its acquisition-date fair value and recognize the resulting gain or loss, if any, in results of operations. The Company applies significant assumptions, estimates, and judgments in determining the fair value of assets acquired and liabilities assumed on the acquisition date, especially with respect to intangible assets and contingent liabilities. Significant estimates in valuing certain intangible assets include, but are not limited to, future expected cash flows from acquired customer bases, acquired technology and acquired trade names, useful lives, royalty rates, and discount rates. Estimates of fair value are based on assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. Any adjustments to provisional amounts that are identified during the measurement period, not to exceed one year from the date of acquisition, are recorded in the reporting period in which the adjustment amounts are determined. Upon the conclusion of the measurement period, any subsequent adjustments are recorded to earnings.

The Company has elected the practical expedient provided under ASC 805, Business Combinations, which allows for contract assets and liabilities acquired or assumed in an acquisition to be measured in accordance with the accounting framework for revenue from contracts with customers as if the Company had originated the acquired contract. This is an exception to the general requirement to measure assets acquired and liabilities assumed at their fair value on the acquisition date.

For a given acquisition, the Company may identify certain pre-acquisition contingencies as of the acquisition date and may extend its review and evaluation of these pre-acquisition contingencies throughout the measurement period in order to obtain sufficient information to assess whether the Company includes these contingencies as a part of the fair value estimates of assets acquired and liabilities assumed and, if so, to determine their estimated amounts.

If the Company cannot reasonably determine the fair value of a pre-acquisition contingency (non-income tax related) by the end of the measurement period, which is generally the case given the nature of such matters, the Company will recognize an asset or a liability for such pre-acquisition contingency if: (i) it is probable that an asset existed or a liability had been assumed at the acquisition date and (ii) the amount of the asset or liability can be reasonably estimated. Subsequent to the measurement period, changes in the Company's estimates of such contingencies will affect earnings and could have a material effect on its results of operations and financial position.

In addition, uncertain tax positions and tax-related valuation allowances assumed in connection with a business combination are initially estimated as of the acquisition date. The Company reevaluates these items based upon facts and circumstances that existed as of the acquisition date with any adjustments to its preliminary estimates being recorded to goodwill, provided that the Company is within the measurement period. Subsequent to the measurement period, changes to these uncertain tax positions and tax-related valuation allowances will affect the Company's provision for income taxes in its consolidated statements of operations and comprehensive income and could have a material impact on its results of operations and financial position.

Transaction costs associated with business combinations are expensed as incurred, and are included in general and administrative expenses in the consolidated statements of operations.

Recent Accounting Pronouncements

Recently Adopted Accounting Pronouncements

The Company adopted ASU No. 2023-07 (Topic 280), Improvements to Reportable Segment Disclosures effective January 1, 2024. This guidance requires enhanced disclosures about significant segment expenses. Additionally, it requires disclosure of the title and position of the individual identified as the CODM and an explanation of how the CODM uses the reported measures of a segment’s profit or loss in assessing segment performance and deciding how to allocate resources. The adoption resulted in expanded segment reporting disclosures, with no impacts to the Company's financial condition and results of operations.

In December 2023, the FASB issued ASU No. 2023-09 (Topic 740), Improvements to Income Tax Disclosures (Topic 740). The ASU requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as an expansion of other income tax disclosures. The ASU is effective on a prospective basis for annual reporting periods beginning

F-22

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

after December 15, 2024. The adoption of this standard impacted our disclosures only and did not affect the Company's financial position or the results of its operations.

Recent Accounting Pronouncements Not Yet Adopted

In November 2024, the FASB issued ASU No. 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40). The ASU requires incremental disclosures about specific expense categories, including but not limited to, purchases of inventory, employee compensation, depreciation, amortization, and selling expenses. The amendments are effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted and the amendments may be applied either prospectively or retrospectively. Management is currently evaluating this ASU to determine its impact on the Company's disclosures.

In May 2025, The FASB issued ASU No. 2025-03, Business Combinations (Topic 805) and Consolidation (Topic 810): Determining the Accounting Acquirer in the Acquisition of a Variable Interest Entity. The ASU revises current guidance for determining the accounting acquirer for a transaction effected primarily by exchanging equity interests in which the legal acquiree is a VIE that meets the definition of a business. The amendments differ from current U.S. GAAP because, for certain transactions, they replace the requirement that the primary beneficiary of a VIE is always the acquirer with an assessment that requires an entity to consider the factors to determine which entity is the accounting acquirer. Under the amendments, acquisition transactions in which the legal acquiree is a VIE will, in more instances, result in the same accounting outcomes as economically similar transactions in which the legal acquiree is a voting interest entity. The ASU does not change the accounting for a transaction determined to be a reverse acquisition or a transaction in which the legal acquirer is not a business and is determined to be the accounting acquiree. The new guidance will become effective for interim and annual reporting periods beginning on January 1, 2027, will require a prospective transition method for business combinations that occur after the initial adoption date, and early adoption is permitted. Management is currently evaluating this ASU to determine its impact on the Company's disclosures.

In July 2025, the FASB issued ASU No. 2025-05, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses for Accounts Receivable and Contract Assets. The ASU provides a practical expedient for estimating expected credit losses on current accounts receivable and current contract assets arising from transactions accounted for under ASC 606. Under the expedient, entities may assume that current conditions as of the balance sheet date do not change for the remaining life of the asset when developing reasonable and supportable forecasts as part of estimating expected credit losses. The ASU is effective for annual reporting periods beginning after December 15, 2025 and interim reporting periods within those annual reporting periods. Early adoption is permitted, and the amendments should be applied prospectively. We do not expect the adoption of ASU 2025-05 to have a material impact on our consolidated financial statements and related disclosures.

In September 2025, the FASB issued ASU No. 2025-06, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. The ASU eliminates all references to prescriptive and sequential software project stages throughout Subtopic 350-40. An entity is required to begin capitalizing software costs when both of the following occur: (1) management has authorized and committed to funding the software project and (2) it is probable that the project will be completed and the software will be used to perform the function intended (referred to as the “probable-to-complete recognition threshold”). The ASU is effective for annual reporting periods beginning after December 15, 2027 and interim reporting periods within those annual reporting periods. Entities may adopt the new guidance using a prospective transition approach, a modified transition approach that is based on the status of the project and whether software costs were capitalized before the date of adoption, or a retrospective transition approach. Early adoption is permitted as of the beginning of an annual reporting period. The Company is currently evaluating the impact this ASU will have on its consolidated financial statements and related disclosures.

In December 2025, the FASB issued ASU No. 2025‑12, Codification Improvements. The ASU provides technical corrections and clarifications to various Topics, including diluted earnings per share, the transfer of receivables from contracts with customers, among other improvements. The ASU is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual periods. Early adoption is permitted in an interim or annual period in which financial statements have not yet been issued or made available for issuance. The Company is currently evaluating the impact this ASU will have on its consolidated financial statements and related disclosures.

F-23

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

3. REVENUE FROM CONTRACTS WITH CUSTOMERS

Disaggregated Revenue

Revenue by operating segment and type of service consist of the following (in millions):

			Year Ended December 31,
			2025						2024						2023
Commercial Real Estate
CoStar			$	1,259					$	1,156					$	1,096
LoopNet			312						282						265
Other Commercial Real Estate			216						77						82
Total Commercial Real Estate			1,787						1,515						1,443
Residential Real Estate			1,460						1,221						1,012
Total revenue			$	3,247					$	2,736					$	2,455

We have recast certain prior period disclosures to align with the way we internally manage our business. See Note 2 for additional information.

The Company is domiciled in the U.S. and revenue earned outside the U.S. were $350 million, $162 million, and $106 million for years ended December 31, 2025, 2024, and 2023, respectively.

Deferred Revenue

Deferred revenue as of December 31, 2025 and 2024 was as follows (in millions):

						December 31,
Balance			Balance Sheet Caption			2025						2024
Current portion			Deferred revenue			$	205					$	137
Non-current portion			Lease and other long-term liabilities			1						—
Total deferred revenue						$	206					$	137

Changes in deferred revenue for the period were as follows (in millions):

Balance at December 31, 2024			$	137
Revenue recognized in the current period from the amounts in the beginning balance			(127)
New deferrals, net of amounts recognized in the current period(1)			194
Effects of foreign currency			2
Balance at December 31, 2025			$	206
__________________________

(1) This balance includes $46 million of net new deferrals from the acquisitions completed in 2025. See Note 4 for further discussion of acquisitions.

Contract Assets

Contract assets are generated when contractual billing schedules differ from revenue recognition timing and represent a conditional right to consideration for satisfied performance obligations that becomes a receivable when the conditions are satisfied. Contract assets as of December 31, 2025 and 2024 were as follows (in millions):

						December 31,
Balance			Balance Sheet Caption			2025						2024
Current portion			Prepaid expenses and other current assets			$	7					$	6
Non-current portion			Deposits and other assets			3						6
Total contract assets						$	10					$	12

F-24

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Revenue was reduced by a net of $2 million from contract assets for the years ended both December 31, 2025 and 2024.

Unsatisfied Performance Obligations

Remaining contract consideration for which revenue had not been recognized due to unsatisfied performance obligations was $527 million at December 31, 2025, which the Company expects to recognize over the next four years. This amount does not include contract consideration for contracts with a duration of one year or less.

Commissions

Commissions expense is included in selling and marketing expense (excluding customer base amortization) in the Company's consolidated statements of operations. Commissions expense activity for the years ended December 31, 2025, 2024, and 2023, was as follows (in millions):

			Year Ended December 31,
			2025						2024						2023
Commissions incurred			$	226					$	180					$	174
Commissions capitalized in the current period			(152)						(120)						(120)
Amortization of deferred commissions costs			141						117						95
Total commissions expense			$	215					$	177					$	149

The Company did not recognize any impairment losses on commissions as of both December 31, 2025 and 2024.

4. ACQUISITIONS

Domain

In February 2025, in connection with the Domain Proposal, the Company acquired approximately 17% of the ordinary shares of Domain, one of Australia's leading property marketplaces, at A$4.20 per share for a total purchase price of A$452 million ($285 million). In May 2025, the Company entered into an agreement to acquire the remaining issued capital of Domain not previously held by CoStar Group by way of Scheme of Arrangement. In August 2025, the Company completed the Domain Acquisition pursuant to which (i) the Company spent A$2.5 billion ($1.6 billion) to acquire the remaining 83% of Domain's ordinary shares; and (ii) Domain shareholders received total cash consideration of A$4.43 per Domain ordinary share, less a one-time special dividend of A$0.088 per share declared and paid by Domain prior to closing. The Domain Acquisition positions the Company to leverage Domain's portfolio of property brands in Australia and CoStar's technology, scale, and innovation to improve customer experience, value, and access to CoStar's brands and product offerings.

As of the closing of the Domain Acquisition, the fair value of the Company's 17% investment was approximately A$465 million ($300 million), measured based on the fair value implied by the consideration transferred. The acquisition was completed as a step-acquisition, and the Company recognized a gain of $14 million, inclusive of dividend income, as a result of remeasuring its previously held equity interest for the year ended December 31, 2025. The gains were recorded in other income (expense), net, in the consolidated statements of operations.

The total purchase consideration for the Domain Acquisition was $1.6 billion, which consisted of the following (in millions):

			Amount
Cash			$	1,472
Settlement of existing debt			139
Fair value of cash settled equity awards related to pre-combination services			1
Total purchase consideration			1,612
Fair value of previously held equity interests			300
			$	1,912

F-25

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The following table summarizes the amounts recorded for acquired assets and assumed liabilities recorded at their fair value as of the closing date of the Domain Acquisition (in millions):

			Preliminary: August 27, 2025						Measurement Period Adjustments						Updated Preliminary: August 27, 2025
Cash and cash equivalents			$	15					$	—					$	15
Accounts receivable			35						—						35
Intangible assets			944						(13)						931
Accrued expenses			(27)						—						(27)
Deferred revenue			(14)						—						(14)
Deferred tax liability			(235)						4						(231)
Other assets and (liabilities), net			(8)						6						(2)
Fair value of identifiable net assets acquired			710						(3)						707
Fair value of NCI in Domain’s partially-owned subsidiaries			(8)						(31)						(39)
Goodwill			1,210						34						1,244
			$	1,912					$	—					$	1,912

Generally, the net assets of Domain were recorded at their estimated fair values upon initial consolidation and the NCI was recorded to fair value as measurement period adjustments. In valuing the acquired assets, assumed liabilities and NCI, fair value estimates were based primarily on future expected cash flows, market rate assumptions for contractual obligations, and appropriate discount rates. The key assumptions used in the valuation include discount rates, royalty rates, projected revenue growth rates, customer attrition rates, and profit margins.

The purchase price allocation is preliminary and subject to change during the measurement period as additional information is obtained about the facts and circumstances that existed at closing. Any material adjustments to provisional amounts identified during the measurement period will be recognized and disclosed in the reporting period in which the adjustment amounts are determined. The primary areas that remain subject to additional information include certain tax matters, the fair value of acquired intangibles, and contingencies.

The following table summarizes the fair values (in millions) of the identifiable intangible assets acquired in the Domain Acquisition, their related estimated useful lives (in years) and their respective amortization methods. The intangible assets were included in the Company's International operating segment prior to the reallocation described in Note 2:

			Estimated Fair Value						Estimated Useful Life						Amortization Method
Customer relationships			$	625					20						Accelerated
Brand and trade names			190						5 - 15						Straight-line
Software			116						2 - 5						Straight-line
Total intangible assets			$	931

Goodwill is calculated as the excess of the consideration transferred over the net assets recognized and represents the future economic benefits arising from other assets acquired that could not be individually identified and separately recognized. Specifically, the goodwill recorded as part of the Domain Acquisition includes, but is not limited to: (i) the expected synergies and other benefits that the Company believes will result from combining Domain's operations with the Company's operations and (ii) any intangible assets that do not qualify for separate recognition, such as the assembled workforce. Of the $1,244 million of goodwill recorded as part of the Domain Acquisition, $994 million was allocated to Residential Real Estate and $250 million to Commercial Real Estate, of which none is expected to be deductible for income tax purposes. Transaction costs associated with the Domain Acquisition were $20 million for the year ended December 31, 2025 and consist primarily of advisory, legal, accounting, and other professional service costs. These costs are included within general and administrative expenses on the consolidated statements of operations.

F-26

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Matterport

On February 28, 2025, the Company completed the Matterport Acquisition. Matterport is a leader in the digitization and datafication of the built world. Matterport’s pioneering technology has set the standard for digitizing, accessing, and managing buildings, spaces, and places online. Matterport’s platform, comprised of innovative software, spatial data-driven data science, and 3D capture technology, has broken down the barriers that have kept the largest asset class in the world, buildings and physical spaces, offline and underutilized for so long. The Company intends to integrate Matterport's 3D digital twin technology with its information service products and online marketplaces to allow buyers, sellers, and renters to explore properties with greater depth and insight.

Pursuant to the terms and conditions of the Matterport Merger Agreement, the Company acquired Matterport, with each share of Matterport Common Stock outstanding immediately prior to the closing of the Matterport Acquisition exchanged for (i) 0.03552 of a CoStar Group Share, the Matterport Merger Exchange Ratio and (ii) $2.75 in cash (the "Matterport Acquisition Consideration"), with fractional shares of CoStar Group Shares paid in cash.

As part of the Matterport Acquisition, the Company issued certain rollover equity awards to the employees of Matterport, which included approximately 2.3 million shares of restricted stock units and approximately 1.8 million stock option awards. The total fair value of the rollover equity awards was $273 million, of which the portion attributable to services performed prior to the acquisition date was allocated to purchase consideration. The remaining fair value was allocated to future services and will be expensed over the remaining service periods as share-based compensation.

The total purchase consideration for the Matterport Acquisition was $1.9 billion, which consisted of the following (in millions):

			Amount
Cash			$	902
CoStar Group Shares (11.7 million shares)			881
Fair value of rollover awards			144
Total			$	1,927

The following table summarizes the amounts recorded for acquired assets and assumed liabilities recorded at their fair value as of the closing date of the Matterport Acquisition (in millions):

			Preliminary: February 28, 2025						Measurement Period Adjustments						Updated Preliminary: February 28, 2025
Cash and cash equivalents			$	55					$	—					$	55
Restricted cash			97						—						97
Accounts receivable			13						—						13
Available for sale investments			204						—						204
Deferred tax assets, net of valuation allowance			25						43						68
Goodwill			1,136						(30)						1,106
Intangible assets			527						—						527
Deferred revenue			(32)						—						(32)
Litigation accrual			(95)						(4)						(99)
Other assets and (liabilities), net			(3)						(9)						(12)
Fair value of identifiable net assets acquired			$	1,927					$	—					$	1,927

Generally, the net assets of Matterport were recorded at their estimated fair values. In valuing the acquired assets and assumed liabilities, fair value estimates were based primarily on future expected cash flows, market rate assumptions for contractual obligations, and appropriate discount rates. The key assumptions used in the valuation include discount rates, royalty rates, projected revenue growth rates, customer attrition rates, and profit margins.

F-27

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The purchase price allocation is preliminary and subject to change during the measurement period as additional information is obtained about the facts and circumstances that existed at closing. Any material adjustments to provisional amounts identified during the measurement period will be recognized and disclosed in the reporting period in which the adjustment amounts are determined. During the year ended December 31, 2025, the Company reassessed its estimates and inputs as new information about facts and circumstances that existed as of the acquisition date became known. As a result, the Company recorded a $30 million reduction in goodwill as a result of measurement period adjustments. The reduction to goodwill consists primarily of adjustments relating to deferred tax assets for net operating losses. The primary areas that remain subject to additional information are the Company's assessment contingencies, including those discussed in Note 11 and fair value assessment of certain acquired intangibles.

The following table summarizes the fair values (in millions) of the identifiable intangible assets acquired in the Matterport Acquisition, their related estimated useful lives (in years), and their respective amortization methods. The intangible assets were included in the Company's North America operating segment prior to the reallocation described in Note 2:

			Estimated Fair Value						Estimated Useful Life						Amortization Method
Developed technology			$	295					9						Straight-line
Customer relationships			140						5						Accelerated
Trade names			92						15						Straight-line
Total intangible assets			$	527

Goodwill is calculated as the excess of the consideration transferred over the net assets recognized and represents the future economic benefits arising from other assets acquired that could not be individually identified and separately recognized. Specifically, the goodwill recorded as part of the Matterport Acquisition includes but is not limited to: (i) the expected synergies and other benefits that the Company believes will result from combining Matterport's operations with the Company's operations and (ii) any intangible assets that do not qualify for separate recognition, such as the assembled workforce. The $1.1 billion of goodwill recorded as part of the Matterport Acquisition was associated with the Company's North America operating segment prior to the reallocation described in Note 2, of which none is expected to be deductible for income tax purposes. Transaction costs associated with the Matterport Acquisition were $18 million during the year ended December 31, 2025 and consist primarily of legal, accounting, and other professional service costs. These costs are included within general and administrative expenses on the consolidated statements of operations.

Visual Lease

In November 2024 CoStar acquired Visual Lease for total consideration of $277 million, in accordance with the terms under the Visual Lease Merger Agreement. Visual Lease is the operator of a SaaS platform for integrated lease management and lease accounting.

The following table summarizes the amounts recorded for acquired assets and assumed liabilities recorded at their fair value as of the closing date of the acquisition (in millions):

			Final: November 1, 2024
Cash and cash equivalents			$	5
Accounts receivable			4
Deferred tax assets			6
Goodwill			150
Intangible assets			136
Deferred revenue			(22)
Other assets and (liabilities), net			(2)
Fair value of identifiable net assets acquired			$	277

The net assets of Visual Lease were recorded at their estimated fair values. In valuing the acquired assets and assumed liabilities, fair value estimates were based primarily on future expected cash flows, market rate assumptions for contractual

F-28

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

obligations, and appropriate discount rates. The key assumptions used in the valuation include discount rates, projected revenue growth rates, customer attrition rates, and profit margins.

The following table summarizes the fair values (in millions) of the identifiable intangible assets acquired in the Visual Lease Acquisition, their related estimated useful lives (in years), and their respective amortization methods. The intangible assets were included in the Company's North America operating segment prior to the reallocation described in Note 2:

			Estimated Fair Value						Estimated Useful Life						Amortization Method
Customer base			$	119					15						Accelerated
Trade name			1						5						Straight-line
Software technology			2						3						Straight-line
Database technology			14						7.5						Straight-line
Total intangible assets			$	136

Goodwill is calculated as the excess of the consideration transferred over the net assets recognized and represents the future economic benefits arising from other assets acquired that could not be individually identified and separately recognized. Specifically, the goodwill recorded as part of the Visual Lease Acquisition includes but is not limited to: (i) the expected synergies and other benefits that the Company believes will result from combining its operations with our CoStar Real Estate Manager operations and (ii) any intangible assets that do not qualify for separate recognition, such as the assembled workforce. The $150 million of goodwill recorded as part of the acquisition is associated with the Company's North America operating segment prior to the reallocation described in Note 2, of which $133 million is expected to be deductible for income tax purposes. Transaction costs associated with the Visual Lease Acquisition were $7 million.

OnTheMarket

On December 12, 2023, CoStar UK acquired OnTheMarket, the operator of onthemarket.com, a U.K. residential property portal. At the time of closing, CoStar UK acquired all of the then issued ordinary share capital of OnTheMarket for cash consideration of 110 pence per share or £94 million ($118 million). OnTheMarket had certain share option contracts that had not been exercised at the time of closing for which CoStar UK has established a liability for £2 million ($3 million). This resulted in total consideration of £96 million ($120 million). Certain shares outstanding at the time of the closing resulted from contracts held by employees of OnTheMarket or its subsidiaries that required OnTheMarket to withhold income and employment taxes of £4 million ($5 million) which represented consideration payable at December 31, 2023 and were remitted in January 2024.

The following table summarizes the amounts recorded for acquired assets and assumed liabilities recorded at their fair value as of the closing date of the acquisition (in millions):

															Final: December 12, 2023
Cash and cash equivalents															$	18
Accounts receivable															2
Goodwill															62
Intangible assets															55
Accrued expenses															(12)
Accrued wages and commissions															(2)
Deferred income taxes, net															(3)
Other assets and liabilities															—
Fair value of identifiable net assets acquired															$	120

The net assets of OnTheMarket were recorded at their estimated fair values. In valuing the acquired assets and assumed liabilities, fair value estimates were based primarily on future expected cash flows, market rate assumptions for contractual obligations, and appropriate discount rates. The estimated fair value of the customer base assets incorporated significant

F-29

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

assumptions that had a material impact on the estimated fair value, such as discount rates, projected revenue growth rates, customer attrition rates, and profit margins.

The following table summarizes the fair values (in millions) of the identifiable intangible assets acquired in the OnTheMarket Acquisition, their related estimated useful lives (in years) and their respective amortization methods. The intangible assets were included in the Company's International operating segment prior to the reallocation described in Note 2:

															Estimated Fair Value						Estimated Useful Life						Amortization Method
Customer base															$	42					8						Accelerated
Trade name															10						15						Straight-line
Technology															3						2						Straight-line
Total intangible assets															$	55

Goodwill is calculated as the excess of the consideration transferred over the net assets recognized and represents the future economic benefits arising from other assets acquired that could not be individually identified and separately recognized. Specifically, the goodwill recorded as part of the OnTheMarket Acquisition includes, but is not limited to: (i) the expected synergies and other benefits that the Company believes will result from combining its operations with international operations and (ii) any intangible assets that do not qualify for separate recognition, such as the assembled workforce. The $62 million of goodwill recorded as part of the acquisition is associated with the Company's International operating segment prior to the reallocation described in Note 2, of which none is expected to be deductible for income tax purposes. Transaction costs associated with the OnTheMarket Acquisition were $11 million.

Pro Forma Financial Information (unaudited)

The unaudited pro forma financial information presented below reflects the consolidated results of operations of the Company assuming both the Domain Acquisition and Matterport Acquisition had taken place on January 1, 2024, Visual Lease Acquisition had taken place on January 1, 2023 and OnTheMarket Acquisition had taken place on January 1, 2022. The material pro forma adjustments primarily consist of incremental amortization expense based on the preliminary fair value of the intangible assets acquired, increased compensation expense relating to the issuance of certain equity plans in connection with the acquisitions, accounting policy alignment adjustments, and the income tax impact of the aforementioned pro forma adjustments. The unaudited pro forma financial information, as presented below, is for informational purposes only and is not necessarily indicative of the results of operations that would have been achieved if the acquisitions had not taken place on the dates listed above.

The unaudited pro forma financial information, in the aggregate, was as follows (in millions):

			Year Ended December 31,
			2025						2024						2023
Revenue			$	3,448					$	3,205					$	2,530
Net income (loss)			$	1					$	(187)					$	355

The impact of the Domain Acquisition on the Company's revenue and net income in the consolidated statements of operations from August 27, 2025 through December 31, 2025 was an increase of $105 million and a decrease of $28 million, respectively. The impact of the Matterport Acquisition on the Company's revenue and net income in the consolidated statements of operations from February 28, 2025 through December 31, 2025 was an increase of $147 million and a decrease of $146 million respectively. The impact of the Visual Lease Acquisition on the Company's revenue and net income in the consolidated statements of operations from November 1, 2024 through December 31, 2024 was not material. The impact of the OnTheMarket Acquisition on the Company's revenue and net income in the consolidated statements of operations from December 12, 2023 through December 31, 2023 was not material.

5. INVESTMENTS AND FAIR VALUE MEASUREMENTS

The Company categorizes assets and liabilities recorded or disclosed at fair value on the consolidated balance sheets based upon the level of judgment associated with inputs used to measure their fair value. The categories are as follows:

F-30

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Level 1 - Observable inputs such as quoted prices in active markets for identical assets or liabilities.

Level 2 - Inputs other than quoted prices in active markets that are either directly or indirectly observable.

Level 3 - Unobservable inputs for which little or no market data exists, therefore requiring an entity to develop its own assumptions.

The Company's financial assets comprised Level 1 cash equivalents with original maturities of three months or less in the amount of $1.4 billion and $4.5 billion as of December 31, 2025 and 2024, respectively. The Company had no Level 2 or Level 3 financial assets measured at fair value as of December 31, 2025 and 2024.

Available-for-sale Debt Securities

In connection with the Matterport Acquisition, the Company acquired $204 million of available-for-sale debt securities, inclusive of $2 million of accrued interest. These securities were sold for net proceeds of $203 million resulting in a negligible realized loss in the first quarter of 2025.

Other Financial Instruments

The Company holds other financial instruments, including cash deposits, accounts receivable, accounts payable, accrued expenses, and Senior Notes. The carrying value for such financial instruments, other than the Senior Notes, each approximated their fair values as of December 31, 2025 and 2024. The estimated fair value of the Company's outstanding Senior Notes using quoted prices from the over-the-counter markets, considered Level 2 inputs, was $900 million as of both December 31, 2025 and 2024.

6. LEASES

The Company has operating and finance leases for its office facilities, data centers, and certain vehicles. The Company's leases have remaining terms up to nine years. The leases contain various renewal and termination options. The period that is subject to an option to extend the lease is included in the lease term if it is reasonably certain that the option will be exercised. The period that is subject to an option to terminate the lease is included if it is reasonably certain that the option will not be exercised.

Lease costs related to the Company's operating and finance leases included in the consolidated statements of operations were as follows (in millions):

			Year Ended December 31,
			2025						2024						2023
Operating lease costs:
Cost of revenue			$	10					$	10					$	10
Selling and marketing (excluding customer base amortization)			16						15						16
Software development			7						9						6
General and administrative			6						7						4
Total operating lease costs			39						41						36
Finance lease costs:
Amortization of ROU assets			3						5						1
Interest on lease liabilities			1						1						—
Total finance lease costs			4						6						1
Total lease costs			$	43					$	47					$	37

Finance lease costs primarily relate to vehicles used by the Company's research teams, and the amortization of the ROU assets are recorded to cost of revenue in the consolidated statements of operations. The impact of lease costs related to short-term leases was not material for the years ended December 31, 2025, 2024, and 2023.

F-31

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Supplemental balance sheet information related to operating leases was as follows (in millions):

						Year Ended December 31,
Balance			Balance Sheet Location			2025						2024
Operating lease liabilities						$	161					$	139
Less: imputed interest						21						18
Present value of lease liabilities						140						121
Less: current portion of lease liabilities			Lease liabilities			23						27
Long-term lease liabilities			Lease and other long-term liabilities			$	117					$	94
Weighted-average remaining lease term in years						5.3						5.6
Weighted-average discount rate						4.7		%				4.4		%
ROU Assets			Lease right-of-use assets			$	123					$	103
Finance lease liabilities						$	12					$	17
Less: imputed interest						1						2
Present value of lease liabilities						11						15
Less: current portion of lease liabilities			Lease liabilities			5						5
Long-term lease liabilities			Lease and other long-term liabilities			$	6					$	10
Weighted-average remaining lease term in years						2.0						3.0
Weighted-average discount rate						6.3		%				6.4		%
ROU Assets			Property and equipment, net			$	13					$	16

Supplemental cash flow information related to leases was as follows (in millions):

			Year Ended December 31,
			2025						2024						2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows used in operating leases			$	36					$	47					$	45
Operating cash flows used in finance leases			$	1					$	1					$	—
Financing cash flows used in finance leases			$	5					$	5					$	1
ROU assets obtained in exchange for new lease obligations:
Operating leases			$	47					$	57					$	29
Finance leases			$	1					$	7					$	14

F-32

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

7. PROPERTY AND EQUIPMENT

Property and equipment consists of the following (in millions):

			December 31,
			2025						2024
Leasehold improvements			$	91					$	81
Furniture, office equipment, and vehicles			70						73
Computer hardware and software			65						54
Aircraft			63						67
Land			70						70
Construction in progress			739						432
Buildings			371						373
Property and equipment, gross			1,469						1,150
Accumulated depreciation and amortization			(146)						(135)
Property and equipment, net			$	1,323					$	1,015

Depreciation expense for property and equipment was approximately $64 million, $57 million and $34 million, for the years ended December 31, 2025, 2024, and 2023, respectively. For the years ended December 31, 2025 and 2024, the Company removed $55 million and $27 million, respectively, of property and equipment that was fully depreciated from property and equipment, gross and accumulated depreciation and amortization, which had no impact on the Company's financial results.

Included in the table above are $263 million and $266 million of buildings and improvements and $27 million and $13 million of accumulated depreciation and amortization related to assets which are partially rented out as operating leases where the Company is the lessor as of December 31, 2025 and 2024, respectively. Materially all of our property and equipment is located in North America.

8. GOODWILL

During the fourth quarter of 2025, the Company realigned our business segments. The table below (in millions) presents the changes in the carrying amount of goodwill by operating segment prior to the realignment and the recast of goodwill under the new segments. See Note 2 for additional information:

			North American						International						Total
Goodwill, December 31, 2023			$	2,149					$	237					$	2,386
Acquisitions, including measurement period adjustments(1)			148						(1)						147
Effect of foreign currency translation			—						(5)						(5)
Goodwill, December 31, 2024			2,297						231						2,528
Acquisitions, including measurement period adjustments(2)			1,108						1,244						2,352
Effect of foreign currency translation			—						64						64
Goodwill, December 31, 2025 prior to reallocation			$	3,405					$	1,539					$	4,944
			Commercial Real Estate						Residential Real Estate						Total
Goodwill, December 31, 2025 after reallocation			$	1,955					$	2,989					$	4,944

(1) North America goodwill generated during the year ended December 31, 2024 from the Visual Lease Acquisition was $150 million.

(2) North America goodwill generated during the year ended December 31, 2025 from the Matterport Acquisition was $1.1 billion. International goodwill generated during the year ended December 31, 2025 from the Domain Acquisition was $1.2 billion.

F-33

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The Company expects $133 million of goodwill generated from acquisitions completed in 2024 to be deductible for tax purposes. Goodwill generated from acquisitions completed in 2025 and 2023 were not deductible for tax purposes.

No impairments of the Company's goodwill were recognized during each of the years ended December 31, 2025, 2024, and 2023.

9. INTANGIBLE ASSETS

Intangible assets consist of the following (in millions, except amortization period data):

			December 31,												Weighted- Average Amortization Period (in years)
			2025						2024
Acquired technology and data			$	471					$	48					8
Accumulated amortization			(55)						(25)
Acquired technology and data, net			416						23
Acquired customer base			1,330						557						15
Accumulated amortization			(403)						(304)
Acquired customer base, net			927						253
Acquired trade names and other intangible assets			524						241						14
Accumulated amortization			(146)						(142)
Acquired trade names and other intangible assets, net			378						99
Acquired above-market leases			42						41						9
Accumulated amortization			(14)						(9)
Acquired above-market leases, net			28						32
Acquired in-place leases			31						32						9
Accumulated amortization			(9)						(6)
Acquired in-place leases, net			22						26
Intangible assets, net			$	1,771					$	433

Amortization expense for intangible assets was approximately $199 million, $90 million, and $74 million for the years ended December 31, 2025, 2024, and 2023, respectively. For the years ended December 31, 2025, 2024, and 2023, the Company removed $62 million, $92 million, and $7 million, respectively, of intangible assets that were fully amortized from the acquired intangible assets and accumulated amortization, which had no impact on the Company's financial results.

In the aggregate, the Company expects the future amortization expense for intangible assets existing as of December 31, 2025 to be approximately $252 million, $219 million, $193 million, $179 million, and $147 million for the years ending December 31, 2026, 2027, 2028, 2029, and 2030, respectively.

Intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value of such assets may not be recoverable. No impairments of the Company's intangible assets were recognized during each of the years ended December 31, 2025, 2024, and 2023.

F-34

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

10. LONG-TERM DEBT

The table below presents the components of outstanding debt (in millions):

			December 31,
			2025						2024
2.800% Senior Notes due July 15, 2030			$	1,000					$	1,000
2024 Credit Agreement, due May 24, 2029			—						—
Total face amount of long-term debt			1,000						1,000
Senior Notes unamortized discount and issuance costs			(7)						(8)
Long-term debt, net			$	993					$	992

Senior Notes

On July 1, 2020, the Company issued $1.0 billion aggregate principal amount of 2.800% Senior Notes due July 15, 2030. The Senior Notes were sold to a group of financial institutions as initial purchasers who subsequently resold the Senior Notes to non-U.S. persons pursuant to Regulation S under the Securities Act, and to persons reasonably believed to be qualified institutional buyers pursuant to Rule 144A under the Securities Act at a purchase price equal to 99.921% of their principal amount. Interest on the Senior Notes is payable semi-annually in arrears on January 15 and July 15. The Senior Notes may be redeemed in whole or in part by the Company (a) at any time prior to April 15, 2030 at a redemption price equal to 100% of the principal amount of the Senior Notes, plus the Applicable Premium (as calculated in accordance with the indenture governing the Senior Notes), and any accrued and unpaid interest, if any, on the principal amount of Senior Notes being redeemed to, but excluding, the redemption date, and (b) on or after April 15, 2030 at a redemption price equal to 100% of the principal amount of the Senior Notes, plus any accrued and unpaid interest, if any, on the principal amount of Senior Notes being redeemed to, but excluding, the redemption date. The Company’s obligations under the Senior Notes are guaranteed on a senior, unsecured basis by the Company’s domestic wholly owned subsidiaries and the indenture governing the Senior Notes contains covenants, events of default, and other customary provisions with which the Company was in compliance as of December 31, 2025.

Revolving Credit Facility

On May 24, 2024, the Company entered into the 2024 Credit Agreement, which provides for a $1.1 billion revolving credit facility with a term of five years (maturing May 24, 2029), and a letter of credit sublimit of $20 million from a syndicate of financial institutions and issuing banks. The 2024 Credit Agreement replaces the Company's 2020 Credit Agreement.

Borrowings bear interest at a floating rate, which can be, at the Company’s option, either (a) an alternate base rate plus an applicable rate ranging from 0.125% to 0.750% or (b) a Term SOFR, SONIA rate, or EURIBOR for the specified interest period plus an applicable rate ranging from 1.125% to 1.750%, in each case depending on the Company’s Debt Rating (as defined in the 2024 Credit Agreement).

The 2024 Credit Agreement contains customary affirmative covenants for transactions of this type, including, among others, the provision of financial and other information to the administrative agent, notice to the administrative agent upon the occurrence of certain material events, preservation of existence, maintenance of properties, and compliance with laws, including environmental laws, subject to certain exceptions. The 2024 Credit Agreement contains customary negative covenants, including, among others, restrictions on the ability of the Company and its subsidiaries to merge and consolidate with other companies, restrictions on the ability of certain subsidiaries to incur indebtedness, and restrictions on the ability of the Company and certain subsidiaries to grant liens or security interests on assets, subject to certain exceptions. The 2024 Credit Agreement contains a financial maintenance covenant that requires the Company to maintain a Total Leverage Ratio (as defined in the 2024 Credit Agreement) of less than or equal to 4.50 to 1.00, tested at the end of each fiscal quarter. The 2024 Credit Agreement also provides for a number of customary events of default, including, among others: payment defaults to the Lenders, voluntary and involuntary bankruptcy proceedings, covenant defaults, material inaccuracies of representations and warranties, cross-acceleration to other material indebtedness, certain change of control events, material money judgments, and other customary events of default. The occurrence of an event of default could result in the acceleration of obligations and the termination of lending commitments under the 2024 Credit Agreement. The Company was in compliance with the covenants in the 2024 Credit Agreement as of December 31, 2025. As of December 31, 2025, the Company had no amounts drawn under this facility.

F-35

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The Company had $3 million and $4 million of deferred debt issuance costs related to the revolving credit facility as of December 31, 2025 and 2024, respectively. These amounts are included in deposits and other assets on the Company's consolidated balance sheets.

The Company recognized interest expense as follows (in millions):

			Year Ended December 31,
			2025						2024						2023
Interest on outstanding borrowings			$	28					$	28					$	28
Amortization of Senior Notes discount and issuance costs			2						3						2
Interest capitalized for construction in progress			(14)						(6)						(2)
Commitment fees and other			3						2						3
Total interest expense			$	19					$	27					$	31

F-36

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

11. INCOME TAXES

The components of the provision for income taxes attributable to operations consist of the following (in millions):

			Year Ended December 31,
			2025						2024						2023
Current:
Federal			$	(14)					$	91					$	126
State			1						28						37
Foreign			1						2						1
Total current			(12)						121						164
Deferred:
Federal			44						(42)						(32)
State			5						(8)						(3)
Foreign			(14)						—						(2)
Total deferred			35						(50)						(37)
Total provision for income taxes			$	23					$	71					$	127

The components of deferred tax assets and liabilities consist of the following (in millions):

			December 31,
			2025						2024
Deferred tax assets:
Allowance for credit losses			$	7					$	5
Accrued compensation			15						13
Stock compensation			28						15
Net operating losses			169						50
Accrued reserve and other			43						20
Lease liabilities			38						26
Capitalized research and development costs			109						140
Research and development credits			36						5
Total deferred tax assets, prior to valuation allowance			445						274
Valuation allowance			(49)						(33)
Total deferred tax assets, net of valuation allowance			396						241
Deferred tax liabilities:
Deferred commission costs, net			(46)						(43)
Lease right-of-use assets			(19)						(16)
Prepaid expenses			(5)						(5)
Property and equipment, net			(3)						(10)
Intangible assets, net			(514)						(144)
Total deferred tax liabilities			(587)						(218)
Net deferred tax assets (liabilities)			$	(191)					$	23

For both the years ended December 31, 2025 and 2024, the Company has not recognized deferred tax liabilities for temporary differences related to investments in foreign subsidiaries that were deemed permanently reinvested. Determination of the amount of unrecognized deferred income tax liabilities on these earnings is not practicable because such liability, if any, depends on certain circumstances existing if and when remittance occurs. A deferred tax liability will be recognized if and when the Company no longer plans to permanently reinvest these undistributed earnings.

F-37

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

As of both December 31, 2025 and 2024, a valuation allowance has been established for certain deferred tax assets due to the uncertainty of realization. The valuation allowance as of both December 31, 2025 and 2024 includes an allowance for acquired net operating losses and foreign deferred tax assets.

The Company established the valuation allowance because it is more likely than not that a portion of the deferred tax asset for certain items will not be realized based on the weight of available evidence. A valuation allowance was established for the foreign deferred tax assets due to the cumulative loss in recent years in those jurisdictions. The Company has not had sufficient taxable income historically to utilize the foreign deferred tax assets, and it is uncertain whether the Company will generate sufficient taxable income in the future to utilize the deferred tax assets. The Company established a valuation allowance for capital losses held by Domain. Capital losses can only offset capital gains in Australia. The Company has established a valuation allowance for certain acquired net operating losses where Section 382 limitations will impact the ability of the Company to utilize the net operating losses before they expire.

The Company’s change in valuation allowance was an increase of approximately $16 million for the year ended December 31, 2025 and an increase of approximately $24 million for the year ended December 31, 2024. The increase for the year ended December 31, 2025 was due to capital losses acquired in the Domain Acquisition and increases in foreign net operating losses. The increase for the year ended December 31, 2024 was primarily due to increases in foreign net operating loss deferred tax assets for which a full valuation allowance has been established.

The Company had U.S. income before income taxes of approximately $122 million, $294 million, and $527 million for the years ended December 31, 2025, 2024, and 2023, respectively. The Company had foreign losses before income taxes of approximately $92 million, $84 million, and $25 million for the years ended December 31, 2025, 2024, and 2023, respectively.

The table below provides the updated requirements of ASU 2023-09 for 2025. See Note 2 for additional details on the adoption of ASU 2023-09.

The effective income tax rate for the year ended December 31, 2025 differs from the statutory federal income tax rate as follows (in millions, except percentages):

			Year Ended December 31, 2025
			Amount						Percentage
Expected federal income tax provision at statutory rate			$	6					21		%
State income taxes, net of federal benefit(1)			6						20
Foreign Tax Effects
United Kingdom
Statutory tax rate difference between United Kingdom and United States			(2)						(7)
Changes in valuation allowances			13						43
Research credits			(1)						(3)
Australia
Statutory tax rate difference between Australia and United States			(4)						(13)
Foreign exchange loss			3						10
Other			(2)						(7)
Tax Credit
Research credits			(21)						(70)
Nontaxable or Nondeductible Items
Nondeductible Compensation			18						60
Transaction Costs			9						29
Stock Based Compensation			(3)						(10)
Other			(1)						(4)
Changes in Unrecognized Tax Benefits			2						7
Income tax expense, net			$	23					77		%

(1) State taxes in CA, DC, IL, NJ, NY, NYC, TX and VA made up the majority (greater than 50 percent) of the tax effect in this category.

F-38

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

As previously disclosed for the years ended December 31, 2024 and 2023, prior to the adoption of ASU 2023-09, the Company’s provision for income taxes resulted in effective tax rates that varied from the statutory federal income tax rate as follows (in millions):

			Year Ended December 31,
			2024						2023
Expected federal income tax provision at statutory rate			$	44					$	105
State income taxes, net of federal benefit			18						27
Increase (decrease) in valuation allowance			22						2
Foreign tax rate differential			(3)						(1)
Research credits			(29)						(20)
Excess tax benefit			(2)						(6)
Tax reserves			7						4
Nondeductible compensation			9						9
Other adjustments			5						7
Income tax expense, net			$	71					$	127

The disaggregation of the income taxes paid (net of refunds) consist of the following (in millions):

			Year Ended December 31,
			2025
Federal			$	40
State			15
Foreign			18
Total income taxes paid			$	73

Income taxes paid (net of refunds) exceeded 5 percent of total income taxes paid (net of refunds) in the following jurisdictions (in millions):

			Year Ended December 31,
			2025
Federal
US			$	40
State
Other States			$	15
Foreign
Australia			$	15

The Company has net operating loss carryforwards for international income tax purposes of approximately $173 million that do not expire. The Company has federal net operating loss carryforwards of approximately $503 million that begin to expire in 2028 and federal income tax credit carryforwards with a tax value of approximately $19 million primarily relating to federal research and development credits that begin to expire in 2032, state net operating loss carryforwards with a tax value of approximately $21 million that begin to expire in 2032 and state income tax credit carryforwards with a tax value of approximately $19 million primarily relating to state research and development credits and the D.C. qualified high technology company tax credit that began to expire in 2026. The Company realized a cash benefit relating to the use of its tax loss carryforwards of approximately $1 million, $3 million, and $6 million in December 31, 2025, 2024, and 2023, respectively.

F-39

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The following table summarizes the activity related to the Company’s unrecognized tax benefits (in millions):

Unrecognized tax benefit as of December 31, 2022			$	16
Increase for current year tax positions			4
Increase for prior year tax positions			2
Expiration of the statute of limitation for assessment of taxes			(2)
Unrecognized tax benefit as of December 31, 2023			20
Increase for current year tax positions			6
Increase for prior year tax positions			5
Expiration of the statute of limitation for assessment of taxes			(4)
Unrecognized tax benefit as of December 31, 2024			27
Increase for current year tax positions			5
Increase for prior year tax positions			2
Expiration of the statute of limitation for assessment of taxes			(4)
Unrecognized tax benefit as of December 31, 2025			$	30

Approximately $30 million and $27 million of the unrecognized tax benefits as of December 31, 2025 and 2024, respectively, would favorably affect the annual effective tax rate if recognized in future periods. The increase for current year tax positions of $5 million and increase for prior year tax positions of $2 million for the year ended December 31, 2025 were primarily attributable to research credits. The decrease for expiration of the statute of limitation of $4 million for the year ended December 31, 2025 was attributable to research credits. The Company recognized $1 million, $1 million, and $1 million for interest and penalties in its consolidated statements of operations for the years ended December 31, 2025, 2024, and 2023, respectively. The Company had liabilities of $3 million, $2 million, and $1 million for interest and penalties in its consolidated balance sheets as of December 31, 2025, 2024, and 2023, respectively. The Company does not anticipate the amount of the unrecognized tax benefits will change significantly over the next 12 months.

The Company is subject to taxation in the U.S. federal jurisdiction and various states and foreign jurisdictions. The Company’s federal income tax returns for tax years 2022 through 2024 remain open to examination. Most of the Company’s state income tax returns for tax years 2022 through 2024 remain open to examination. For states that have a four-year statute of limitations, the state income tax returns for tax years 2021 through 2024 remain open to examination. The Company’s U.K. income tax return for tax year 2024 remains open to examination. The Company believes that an adequate provision has been made for any adjustments that may result from tax examinations.

F-40

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

12. COMMITMENTS AND CONTINGENCIES

The following summarizes the Company's significant contractual obligations, including related payments due by period, as of December 31, 2025 (in millions):

Year Ending December 31,						Operating lease obligations						Finance lease obligations						Long-term debt principal payments						Long-term debt interest payments
2026						$	29					$	6					$	—					$	28
2027						33						5						—						28
2028						33						1						—						28
2029						24						—						—						28
2030						19						—						1,000						28
Thereafter						23						—						—						—
Total						$	161					$	12					$	1,000					$	140

The Company leases office facilities under various non-cancelable operating leases, as well as data centers and vehicles under finance lease arrangements. The leases contain various renewal options.

See Note 6 for further discussion of the Company's lease commitments.

Litigation

Currently, and from time to time, the Company is involved in litigation incidental to the conduct of its business. The Company records a provision for a liability when it is both probable that a liability has been incurred and the amount can be reasonably estimated. While it is reasonably possible that an unfavorable outcome may occur as a result of one or more of the Company’s current litigation matters, at this time, management has concluded that the resolutions of these matters are not expected to have a material effect on the Company's consolidated financial position, future results of operations, or liquidity. Legal defense costs are expensed as incurred, except as set forth below.

Matterport-Related Matters

On July 23, 2021, plaintiff William J. Brown, a former employee and a stockholder of Matterport, sued Matterport, Gores Holdings VI, Inc. (now known as Matterport, Inc.), Maker Merger Sub Inc., Maker Merger Sub II, LLC, and Matterport directors R.J. Pittman, David Gausebeck, Matt Bell, Peter Hebert, Jason Krikorian, Carlos Kokron and Michael Gustafson (collectively, the “Brown Defendants”) in the Court of Chancery of the State of Delaware (the “Chancery Court ”). Brown claimed that the Brown Defendants imposed invalid transfer restrictions on his shares of Matterport stock in connection with the Gores Merger transactions (the "Gores Transaction" and the Agreement and the Plan of Merger thereunder, the "Gores Merger Agreement") between Matterport, Inc. and Legacy Matterport (the “Transfer Restrictions”), and that Matterport’s Board of Directors violated their fiduciary duties in connection with a purportedly misleading letter of transmittal. An expedited trial regarding the facial validity of the Transfer Restrictions took place in December 2021. On January 11, 2022, the court issued a ruling that the Transfer Restrictions did not apply to Brown. Separate proceedings regarding Brown's remaining claims, including the amount of any damages suffered by Brown were the subject of the second phase of the case. Legacy Matterport's position was that Brown did not suffer any damages as he would have sold his shares as soon as possible after the Gores Transaction closed had Legacy Matterport not prevented him from trading based on its application of the Transfer Restrictions. Trial was held in November 2023, and a post-trial hearing was held on February 22, 2024. On May 28, 2024, the court ruled that Matterport had a reasonable basis to deny the plaintiff’s November 2021 demand that the transfer restrictions be removed from his shares and that the plaintiff lacked standing as to whether the transfer restrictions complied with Delaware law. However, the court awarded Brown $79 million plus pre- and post-judgment interest as damages for losses caused by Matterport’s initial refusal to issue freely transferable shares (the “Brown Judgment”). On July 29, 2024, a notice of appeal to the court's ruling to the Delaware Supreme Court was filed. Brown filed a notice of cross-appeal on August 12, 2024. Oral argument on the appeal was heard on February 26, 2025. On April 22, 2025, the Delaware Supreme Court substantially affirmed the Chancery Court's $79 million damages award but reversed and remanded for additional proceedings on the manner in which post-judgment interest was calculated.

The Company has estimated a litigation accrual of $99 million as of December 31, 2025, considering the substantially-affirmed damages award and the Company's estimate of the expected interest award using the Chancery Court's previously

F-41

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

determined interest methodology. This estimated litigation accrual is reflected in the purchase price allocation for the Matterport Acquisition and is subject to change based on the Chancery Court's revised ruling. The Company anticipates the revised ruling will occur by the first half of 2026. The Company estimated additional interest of up to approximately $17 million could be awarded if the Chancery Court followed the methodology Brown previously argued, and which was rejected. Subsequent to the Brown Judgment, on August 14, 2024, a litigation bond was posted, and Matterport transferred $95 million in cash as collateral into a designated insured interest-bearing account, which is classified as restricted cash on the Company’s consolidated balance sheet as of December 31, 2025.

Since the Brown judgment in May 2024, other former Legacy Matterport stockholders have filed complaints (the “Post-Brown Complaints”) in the Chancery Court alleging that they were prevented from trading their Matterport shares through invalid transfer restrictions. These complaints were filed as follows: on July 19, 2024 by Damien Leostic and William Schmitt; on August 16, 2024 by Greg Coombe; on September 19, 2024 by Build Legacy LLC, Build the Future Trust under agreement dated November 16, 2023, Penchant Capital LLC, Penchant Trust, and iRobot Corporation. On September 16, 2024, Kimberly Burdi-Dumas, a former Matterport employee, filed a putative class action complaint on behalf of all persons or entities who were stockholders of Legacy Matterport as of July 21, 2021, and who, pursuant to the Gores Transaction, were thereafter issued and held Matterport shares that were improperly restricted from being sold until January 18, 2022. On November 26, 2024, Schmitt amended his complaint to bring a class action on behalf of former members of Matterport who did not receive their shares immediately following the closing of Gores Transaction. On December 6, 2024, the Burdi-Dumas complaint was amended to include a second plaintiff, Janet Day, and additional claims. These cases have now been consolidated and coordinated.

The Company monitors developments in these legal matters that could affect the estimate the Company may have previously accrued. As of December 31, 2025, there were no amounts accrued that the Company believes would be material to its financial position, except as noted above. Further, the range of reasonably possible losses in excess of accrued liabilities currently cannot be reasonably estimated, except as noted above.

13. SEGMENT REPORTING

Segment Information

The Company manages its business by product portfolios in two operating segments and two reportable segments, with the primary areas of measurement and decision-making being Commercial Real Estate and Residential Real Estate. Segment reporting is aligned with the internal reporting used by the CODM, which is the Company’s Chief Executive Officer. The CODM relies on a management reporting process that provides operating segment revenue, EBITDA, and Adjusted EBITDA for making decisions and assessing performance as the source of the Company’s reportable segments. EBITDA and Adjusted EBITDA are used by management internally to measure operating and management performance and to evaluate the business. The CODM does not review any information regarding total assets by operating segment.

Operating results by segment include items that are directly attributable to each segment and shared expenses such as IT expenses, corporate infrastructure costs including facilities, finance, and legal. Shared expenses are allocated based on revenue and headcount. There are no intersegment transactions. The impact of certain items that are not normal, recurring, cash operating expenses necessary to run the operating segment are removed to determine Adjusted EBITDA and include stock based compensation, acquisition and integration costs, restructuring and related costs, and settlements and impairments.

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COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

We have recast certain prior period disclosures to align with our reportable segments. See Note 2 for additional information.

Summarized EBITDA and Adjusted EBITDA information by operating segment consists of the following (in millions):

			Commercial Real Estate						Residential Real Estate						Total
Year Ended December 31, 2025
Revenue(1)			$	1,787					$	1,460					$	3,247
Less:
Personnel			861						696						1,557
Marketing			77						771						848
General and administrative (2)			369						303						672
EBITDA			480						(310)						170
Stock-based compensation expense			151						43						194
Acquisition and integration related costs			36						27						63
Restructuring and related costs			4						2						6
Settlements and impairments			1						8						9
Adjusted EBITDA			$	672					$	(230)					$	442
Year Ended December 31, 2024
Revenue(1)			$	1,515					$	1,221					$	2,736
Less:
Personnel			622						577						1,199
Marketing			64						795						859
General and administrative (2)			310						245						555
EBITDA			519						(396)						123
Stock-based compensation expense			55						34						89
Acquisition and integration related costs			29						—						29
Restructuring and related costs			—						1						1
Settlements and impairments			(1)						—						(1)
Adjusted EBITDA			$	602					$	(361)					$	241
Year Ended December 31, 2023
Revenue(1)			$	1,443					$	1,012					$	2,455
Less:
Personnel			608						429						1,037
Marketing			92						468						560
General and administrative(2)			266						202						468
EBITDA			477						(87)						390
Stock-based compensation expense			56						29						85
Acquisition and integration related costs			—						13						13
Restructuring and related costs			3						1						4
Adjusted EBITDA			$	536					$	(44)					$	492
___________________
(1) See Note 3 for revenue by segment.
(2) Excludes personnel costs.

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COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The reconciliation of Adjusted EBITDA and EBITDA to income before income tax expense consists of the following (in millions):

			Year Ended December 31,
			2025						2024						2023
Adjusted EBITDA			$	442					$	241					$	492
Stock-based compensation expense			(194)						(89)						(85)
Acquisition and integration related costs			(63)						(29)						(13)
Restructuring and related costs			(6)						(1)						(4)
Settlements and impairments			(9)						1						—
EBITDA			170						123						390
Amortization of acquired intangible assets in cost of revenue			(74)						(30)						(32)
Amortization of acquired intangible assets in operating expenses			(118)						(44)						(42)
Depreciation and other amortization			(50)						(44)						(34)
Interest income, net			110						213						214
Other income (expense), net (1)			(8)						(8)						6
Income before income taxes			$	30					$	210					$	502
__________________________
(1) Includes 21 million and 29 million of depreciation and amortization expense, including above-market lease amortization, associated with lessor activities for the years ended December 31, 2025 and 2024, respectively.

14. STOCKHOLDERS' EQUITY

Share Repurchase Program

Prior Stock Repurchase Program and Accelerated Share Repurchase Agreement

In February 2025, the Board of Directors approved the Prior Stock Repurchase Program which authorized the repurchase of up to $500 million of CoStar Group Shares. Prior to November 6, 2025, the Company purchased $138 million of CoStar Group Shares pursuant to a 10b5-1 Plan.

On November 6, 2025, the Company entered into an ASR agreement with a financial institution counterparty to repurchase $300 million of its outstanding common stock. The Company repurchased 4.5 million CoStar Group Shares during the term of the ASR Agreement based on the volume-weighted average price, net of discount, of $66.98 per share over the duration of the program, which was completed in November 2025. The share repurchases were recorded as a reduction to stockholders’ equity.

During the year ended December 31, 2025, the Company repurchased a total of 7.1 million CoStar Group Shares for an aggregate cost of $500 million under the Prior Stock Repurchase Program and ASR Agreement. As a result, no balance remained available for repurchases under that program. The aggregate purchase price of CoStar Group Shares is recorded as Treasury Stock and presented as a reduction to stockholders' equity.

New Stock Repurchase Program

In December 2025, the Board of Directors approved a Stock Repurchase Program which authorizes, but does not obligate, the repurchase of up to $1.5 billion of CoStar Group Shares. Stock repurchases may be effected through open market repurchases in compliance with Rule 10b-18 under the Exchange Act or through a trading plan adopted in accordance with Rule 10b5-1 of the Exchange Act. Repurchases may be made from time to time at management's discretion, and the timing and amount of any such repurchases will be determined based on share price, market conditions, legal requirements, and other relevant factors. The program has no time limit and can be discontinued at any time at the Company’s discretion.

No shares were repurchased under the Stock Repurchase Program during the year ended December 31, 2025. As of December 31, 2025, $1.5 billion remains available for repurchases under the Stock Repurchase Program.

Shares of common stock repurchased under the share repurchase program become treasury shares and are accounted for when the transaction is settled. Direct costs incurred to acquire the shares are included in the total cost of the shares.

F-44

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Preferred Stock

The Company has 2.0 million shares of preferred stock, $0.01 par value, authorized for issuance. The Board of Directors may issue the preferred stock from time to time as shares of one or more classes or series.

Common Stock

The Company has 1.2 billion shares of common stock authorized for issuance. Dividends may be declared and paid on the common stock, subject in all cases to the rights and preferences of the holders of preferred stock and authorization by the Board of Directors. In the event of liquidation or winding up of the Company and after the payment of all preferential amounts required to be paid to the holders of any series of preferred stock, any remaining funds shall be distributed among the holders of the issued and outstanding common stock.

15. EARNINGS PER SHARE

The following table sets forth the calculation of basic and diluted earnings per share (in millions, except per share data):

			Year Ended December 31,
			2025						2024						2023
Numerator:
Net income			$	7					$	139					$	375
Denominator:
Denominator for basic earnings per share — weighted-average outstanding shares			416.8						406.3						405.3
Effect of dilutive securities:
Stock options, restricted stock awards and restricted stock units			3.9						1.5						1.6
Denominator for diluted earnings per share — weighted-average outstanding shares			420.7						407.8						406.9
Earnings per share — basic			$	0.02					$	0.34					$	0.92
Earnings per share — diluted			$	0.02					$	0.34					$	0.92

The following table summarizes the shares underlying the unvested performance-based restricted stock and anti-dilutive securities excluded from the basic and diluted earnings per share calculations (in millions):

			Year Ended December 31,
			2025						2024						2023
Performance-based restricted stock awards			0.1						0.1						0.2
Anti-dilutive securities			1.7						0.8						0.7

16. EMPLOYEE BENEFIT PLANS

Stock Incentive Plans

In April 2016, the Company’s Board of Directors adopted the CoStar Group 2016 Stock Incentive Plan (as amended, the “2016 Plan”), subject to stockholder approval, which was obtained on June 9, 2016. On April 28, 2025, the Board of Directors approved the CoStar Group, Inc. 2025 Stock Incentive Plan (the “2025 Plan”), subject to stockholder approval, which was obtained on June 26, 2025. All shares of common stock that were authorized for issuance under the 2016 Plan that, as of April 28, 2025, remained available for issuance under the 2016 Plan (excluding shares subject to outstanding awards) were rolled into the 2025 Plan and, following stockholder approval of the 2025 Plan, no further grants will be made under the 2016 Plan.

The 2025 Plan provides for the grant of stock options, restricted stock, restricted stock units, and stock appreciation rights to officers, employees, and directors of the Company and its subsidiaries. Stock options granted under the 2025 Plan may be non-qualified or may qualify as incentive stock options. Except in limited circumstances related to a merger or other acquisition, the exercise price for an option may not be less than the fair market value of the Company’s common stock on the date of grant. The vesting period for each grant of options, restricted stock, restricted stock units, and stock appreciation rights

F-45

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

under the 2025 Plan is determined by the Board of Directors or a committee thereof and is generally three to four years, subject to minimum vesting periods of at least one year. In some cases, vesting of awards under the 2025 Plan may be based on performance conditions. The Company initially reserved approximately 13.2 million shares of common stock for issuance under the 2025 Plan, which included shares of common stock that were authorized and remained available for issuance under the 2016 Plan as of April 28, 2025. Any shares of common stock subject to (a) outstanding awards under the 2016 Plan as of April 28, 2025 or (b) outstanding awards under the 2025 Plan that cease for any reason to be subject to such awards (other than by reason of exercise or settlement of the awards to the extent they are exercised or settled in vested and nonforfeitable shares) will become authorized and unissued under the 2025 Plan. Unless terminated sooner, the 2025 Plan will terminate in June 2035, but will continue to govern unexercised and unexpired awards issued under the 2025 Plan prior to that date. Approximately 9.7 million shares were available for future grant under the 2025 Plan as of December 31, 2025.

In connection with the Matterport Acquisition, the Company assumed Matterport's 2021 Incentive Award Plan and Matterport's Amended and Restated 2011 Stock Incentive Plan, including outstanding restricted stock units and stock options originally granted by Matterport under the Assumed Matterport Plans to continuing employees. These assumed awards will vest in accordance with their original terms, generally over four years. The Company does not intend to issue further grants under these plans. Shares forfeited due to employee termination or expiration are returned to the share pool. As of December 31, 2025, approximately 2.1 million shares remained available under the Assumed Matterport Plans.

As of December 31, 2025, there was approximately $247 million of unrecognized compensation cost related to stock incentive plans, net of estimated forfeitures, which the Company expects to recognize over a weighted-average-period of 2.5 years. The income tax benefit realized from stock-based compensation was $5 million, $2 million and $7 million for the years ended December 31, 2025, 2024 and 2023, respectively. See Notes 2 for further discussion of stock-based compensation expense.

Stock Options

Option activity was as follows:

			Number of Shares						Weighted-Average Exercise Price						Weighted-Average Remaining Contract Life (in years)						Aggregate Intrinsic Value (in millions)
Outstanding at December 31, 2022			2,178,200						$	41.79					5.60						$	80
Granted			140,800						$	76.78
Exercised			(419,340)						$	17.77
Outstanding at December 31, 2023			1,899,660						$	46.69					5.53						$	72
Granted			152,900						$	82.47
Exercised			(122,736)						$	58.03
Canceled or expired			(25,234)						$	72.66
Outstanding at December 31, 2024			1,904,590						$	51.48					4.80						$	44
Assumed in Matterport Acquisition			1,799,170						$	9.54
Granted			212,700						$	78.33
Exercised			(686,735)						$	9.76
Canceled or expired			(26,000)						$	91.98
Outstanding at December 31, 2025			3,203,725						$	38.32					3.96						$	102
Exercisable at December 31, 2023			1,571,105						$	44.32					4.93						$	68
Exercisable at December 31, 2024			1,615,687						$	46.75					4.15						$	44
Exercisable at December 31, 2025			2,849,289						$	33.22					3.38						$	102

The aggregate intrinsic value of outstanding options is calculated as the difference between (i) the closing price of the common stock at the end of the period and (ii) the exercise price of the underlying awards, multiplied by the number of outstanding options as of the end of the period that had an exercise price less than the closing price on that date. The aggregate

F-46

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

intrinsic value of options exercised, determined as of the exercise date, was approximately $48 million, and $4 million, and $24 million for the years ended December 31, 2025, 2024 and 2023, respectively.

The Company estimated the fair value of each option granted on the date of grant using the Black-Scholes option-pricing model, using the assumptions in the following table:

			Year Ended December 31,
			2025						2024						2023
Dividend yield			0		%				0		%				0		%
Expected volatility			35		%				35		%				35		%
Risk-free interest rate			4.29		%				4.28		%				3.96		%
Expected life (in years)			5						5						5
Weighted-average grant date fair value			$	30.05					$	31.57					$	28.87

The expected dividend yield is determined based on the Company's past cash dividend history and anticipated future cash dividend payments. The Company has never declared nor paid any dividends on its common stock and does not anticipate paying any dividends on its common stock during the foreseeable future, but intends to retain any earnings for future growth of its business. Expected volatility is calculated based on historical volatility of the daily closing price of the Company's common stock over a period consistent with the expected life of the options granted. The risk-free interest rate is based on the U.S. Treasury rate with terms similar to the expected life of the options granted. The expected life for the options is determined based on multiple factors, including historical employee behavior patterns of exercising options and post-employment termination behavior as well as expected future employee option exercise patterns.

The following table summarizes information regarding options outstanding at December 31, 2025:

						Options Outstanding																		Options Exercisable
Range of Exercise Price						Number of Shares						Weighted-Average Remaining Contractual Life (in years)						Weighted-Average Exercise Price						Number of Shares						Weighted-Average Exercise Price
$4.73 - $9.59						1,051,854						3.18						$	9.16					1,051,854						$	9.16
$9.60 - $27.35						406,581						1.69						$	19.47					406,581						$	19.47
$27.36 - $53.24						697,090						2.62						$	36.97					697,090						$	36.97
$53.25 - $77.56						549,600						5.38						$	69.05					509,799						$	68.44
$77.57 - $91.98						498,600						7.76						$	83.24					183,965						$	89.35
						3,203,725						3.96						$	38.32					2,849,289						$	33.22

Restricted Stock Awards

The Company grants restricted common stock to certain executive officers, directors, and employees of the Company which vest over a specific service period. Executive officers also receive restricted common stock that vests based on the achievement of certain operating performance goals over a three-year performance period. The grant of awards with performance conditions supports the Company’s goal of aligning executive incentives with long-term stockholder value and ensuring that executive officers have a continuing stake in the long-term success of the Company.

The vesting of restricted common stock is subject to continuing employment requirements. Certain performance-based restricted common stock awards are also subject to a market condition such that the actual number of shares that vest at the end of the respective three-year period is determined based on the Company’s achievement of performance goals and an established Company specific TSR factor relative to the S&P 500 Index over the same three-year performance period. At the end of the three-year performance period, if the performance condition is achieved at or above the pre-established threshold, the number of shares earned is further adjusted by a TSR payout percentage, which ranges between 80% and 120%, based on the Company’s TSR performance relative to that of S&P 500 Index over the respective three-year period.

F-47

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

The Company estimates the fair value of its performance-based restricted stock awards with market conditions on the date of grant using a Monte-Carlo simulation valuation model. This pricing model uses multiple simulations to evaluate the probability of achieving the market condition to calculate the fair value of the awards. Expense is only recorded for awards that are expected to vest, net of estimated forfeitures. The assumptions used to estimate the fair value of performance-based restricted stock awards with market conditions were as follows:

			Year Ended December 31,
			2025						2024						2023
Dividend yield			0		%				0		%				0		%
Expected volatility			31		%				34		%				37		%
Risk-free interest rate			4.23		%				4.47		%				4.31		%
Expected life (in years)			3						3						3
Weighted-average grant date fair value			$	85.29					$	86.96					$	81.58

The expected dividend yield is determined based on the Company's past cash dividend history and anticipated future cash dividend payments. The Company has never declared nor paid any dividends on its common stock and does not anticipate paying any dividends on its common stock during the foreseeable future, but intends to retain any earnings for future growth of its business. Expected volatility is calculated based on historical volatility of the daily closing price of the common stock of the companies within the S&P 500 Index over a period consistent with the expected life of the awards. The risk-free interest rate is based on the U.S. Treasury rate with terms similar to the expected life of the awards. The expected life is consistent with the performance measurement period of the awards.

As of December 31, 2025, the Company determined that it was probable that at least the minimum performance goals associated with restricted stock awards with performance and market conditions granted during 2025, 2024, and 2023 would be met by their forfeiture dates. The Company recorded a total of approximately $10 million, $7 million, and $14 million of stock-based compensation expense related to restricted stock awards with performance and market conditions for the years ended December 31, 2025, 2024, and 2023, respectively, As of December 31, 2025, the Company expects to record an aggregate stock-based compensation expense of approximately $24 million for performance-based restricted stock awards over the periods 2026, 2027, and 2028.

The following table presents unvested restricted stock awards activity for the year ended December 31, 2025:

			Restricted Stock Awards — without Market Condition												Restricted Stock Awards — with Market Condition
			Number of Shares						Weighted-Average Grant Date Fair Value per Share						Number of Shares						Weighted-Average Grant Date Fair Value per Share
Unvested restricted stock awards at December 31, 2024			2,554,989						$	76.19					733,200						$	81.49
Granted			2,316,296						$	79.04					435,120						$	85.29
Vested			(898,926)						$	74.47					(124,068)						$	71.19
Canceled			(329,149)						$	75.81					(48,252)						$	71.19
Unvested restricted stock awards at December 31, 2025			3,643,210						$	78.32					996,000						$	84.93

F-48

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Restricted Stock Units

The following table presents unvested restricted stock units activity for the year ended December 31, 2025:

			Number of Units						Weighted-Average Grant Date Fair Value per Share
Unvested restricted stock units at December 31, 2024			23,532						$	73.88
Assumed in Matterport Acquisition			2,256,423						$	75.63
Granted			115,654						$	78.57
Vested			(1,304,354)						$	75.60
Canceled			(376,335)						$	75.64
Unvested restricted stock units at December 31, 2025			714,920						$	76.09

Management Stock Purchase Plan

The Board of Directors originally adopted the Company’s Management Stock Purchase Plan in December 2017 and the plan was subsequently amended and restated in December 2025. The intent of the MSPP is to provide select key employees of the Company and its subsidiaries, including the Company's executive officers, the opportunity to defer a portion of their cash incentive compensation and to align management and stockholder interests through awards of DSUs under the MSPP and awards of Matching RSUs issued under the Company's 2016 Plan and 2025 Plan. Under the MSPP, participants are permitted to elect to defer up to 90% (or such other percentage determined by the Compensation Committee of the Board of Directors) of their annual incentive bonus or commissions earned during the year by submitting an irrevocable election in accordance with Section 409A of the Internal Revenue Code, as amended. On the date the incentive bonus or commission would otherwise be paid in cash (typically during the following calendar year), the Company awards the participant DSUs representing the number of shares of common stock with an aggregate fair market value on that date equal to the amount of compensation elected to be deferred under the MSPP. On the same date the DSUs are awarded, the participant receives a grant of Matching RSUs covering the number of shares of common stock equal up to 100% of the DSUs granted. The expense related to the DSUs is recognized on a straight-line basis during the period that the related incentive bonus or commission is earned. The Company granted 95,936 and 57,498 DSUs during the years 2025 and 2024, respectively. The expense related to the Matching RSUs is recognized over the four-year vesting period following the grant date.

The following tables presents the Matching RSU activity for the year ended December 31, 2025:

			Number of Matching RSU Shares						Weighted-Average Grant Date Fair Value per Share
Unvested MSPP restricted stock units at December 31, 2024			174,730						$	72.17
Granted			95,936						$	77.60
Vested			(22,670)						$	83.79
Canceled			(7,613)						$	78.84
Unvested MSPP restricted stock units at December 31, 2025			240,383						$	73.03

Employee 401(k) Plan

The Company maintains a 401(k) Plan as a defined contribution retirement plan for all eligible employees. The 401(k) Plan provides for tax-deferred contributions of employees’ salaries, limited to a maximum annual amount as established by the IRS. In addition to the traditional 401(k), effective January 1, 2015, eligible employees have the option of making an after-tax contribution to a Roth 401(k) plan or a combination of both. In each of 2025, 2024, and 2023, the Company matched 100% of employee contributions up to a maximum of 4% of total compensation. Amounts contributed to the 401(k) Plan by the Company to match employee contributions for the years ended December 31, 2025, 2024, and 2023 were approximately $33

F-49

COSTAR GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

million, $26 million, and $26 million, respectively. The Company had no administrative expenses in connection with the 401(k) Plan for each of the years ended December 31, 2025, 2024, and 2023.

Employee Pension Plan

The Company maintains a GPP Plan for all eligible employees in the Company’s U.K. offices. The GPP Plan is a defined contribution plan. Employees are eligible to contribute a portion of their salaries, subject to a maximum annual amount as established by Her Majesty's Revenue and Customs. In each of 2025, 2024, and 2023, the Company's matching contribution was based on the percentage contributed by the employee, up to a maximum of 6% of total compensation. Amounts contributed to the GPP Plan by the Company to match employee contributions for the years ended December 31, 2025, 2024, and 2023, were approximately $2 million, $2 million, and $1 million, respectively.

Employee Stock Purchase Plan

As of August 1, 2006, the Company introduced an ESPP, pursuant to which eligible employees participating in the plan authorize the Company to withhold specified amounts from the employees’ compensation and use the withheld amounts to purchase CoStar Group Shares at 90% of the market price. Participating employees are able to purchase common stock under this plan during each offering period. An offering period begins the second Saturday before each of the Company’s regular pay dates and ends on each of the Company’s regular pay dates. On June 2, 2021, the Company’s stockholders approved an amendment to the ESPP to increase the number of shares available for purchase under the ESPP by 9.7 million shares. The Company registered the issuance of these additional shares under the ESPP pursuant to the registration statement filed on July 28, 2021. There were 292,559 and 544,587 shares available for purchase under the ESPP as of December 31, 2025 and 2024, respectively, and approximately 252,028 and 237,741 CoStar Group Shares were purchased under the ESPP during 2025 and 2024, respectively.

17. SUBSEQUENT EVENTS

The Company has evaluated subsequent events and transactions that occurred after the balance sheet date up to the date that the consolidated financial statements were issued. Based upon this review, the Company did not identify any material subsequent events that required adjustment or disclosure in the consolidated financial statements.

F-50