Item 1A. Risk Factors

In addition to the other information set forth in this Report, you should carefully consider the factors disclosed in Part I, “Item 1A Risk Factors” in our 2023 Form 10-K, which could materially affect our business, financial condition or future results. Additional risks and uncertainties not currently known to us, or that we currently deem to be immaterial, may also have a material adverse effect on our business, financial condition and/or results of operations. Other than the following items, there have not been any material changes to the risk factors as previously disclosed in Part I, “Item 1A Risk Factors” in our 2023 Form 10-K.

Risks related to our business

We may be unable to complete the acquisition of Matterport or otherwise realize the benefits of the pending Matterport acquisition, which could have an adverse effect on us.

On April 22, 2024, we announced that we had entered into the Merger Agreement to acquire Matterport. Pursuant to the Merger Agreement, and subject to the terms and conditions contained therein, at the closing of the acquisition, we will acquire all of the outstanding shares of Matterport in a cash and stock transaction. The closing of the acquisition is subject to certain conditions, including: expiration or termination of the applicable waiting periods under applicable antitrust laws; approval for listing on Nasdaq Global Select Market of the CoStar Group Shares to be issued in the transaction; no injunction, law or order prohibiting the Mergers; accuracy of each party’s representations, subject in most cases to materiality or material adverse effect qualifications; compliance by each party with its covenants in all material respects; and with respect to the other party, there not having occurred since the date of the Merger Agreement any event, development, change or occurrence that has had or would reasonably be expected to have had, individually or in the aggregate, a material adverse effect. On July 3, 2024, Matterport and CoStar Group each received a request for additional information and documentary materials (the “Second Request”) from the FTC in connection with the FTC’s review of the Transaction. The effect of the Second Request is to extend the waiting period imposed by the HSR Act until 30 days after Matterport and CoStar Group have each substantially complied with their respective Second Requests, unless that period is extended or terminated sooner by the FTC. CoStar Group and Matterport are working with the FTC to complete its investigation as soon as practicable. There can be no assurance that the closing conditions will be satisfied or waived or that the transaction will be completed. The failure to satisfy these conditions could delay the completion of the acquisition or prevent it from occurring. Any delay in completing the acquisition could cause us to not realize some or all of the benefits that we expect to achieve. Further, even if we are unable to complete the acquisition, we will still have incurred substantial expenses and diverted significant management time and resources from our ongoing business.

Until the completion of the acquisition, we will operate independently of Matterport. It is possible that the pendency of the acquisition could result in the loss of key employees, higher than expected costs, diversion of management attention, or the disruption of our ongoing businesses, which may adversely affect the combined company’s ability to maintain relationships with customers, vendors and employees or to achieve the anticipated benefits of the acquisition. In addition, the amount of stock consideration offered per Matterport share is based on an exchange ratio that will be fixed prior to closing, subject to a collar, based on our share price, and will not be adjusted to account for changes in Matterport’s business, assets, liabilities, prospects, outlook, financial condition or results of operations, or any other changes during the pendency of the acquisition, including any change in the market price of, analyst estimates of or projections relating to Matterport’s common stock.

We have incurred, and we will continue to incur, transaction fees, including legal, regulatory and other costs associated with closing the transaction, as well as expenses related to formulating and implementing integration plans, including systems consolidation costs and employment-related costs. We may be unable to offset transaction and integration-related costs with the realization of other efficiencies related to the integration of the business.

The success of the Matterport acquisition, if completed, will depend in part on our ability to realize the anticipated business opportunities and growth prospects from combining our business with that of Matterport. We may never realize these business opportunities and growth prospects. We do not have experience in Matterport’s business in 3D digital technology or in manufacturing cameras. Matterport’s business is also subject to risks and uncertainties. There can be no assurances we will

have success in these industries. Integrating operations will require significant efforts and expenditures. If we are unable to successfully or timely acquire and integrate Matterport’s business with ours, we may be unable to realize the growth, synergies and other anticipated benefits resulting from the acquisition and our business could be adversely affected.

If internet search engines do not prominently feature our websites on the search engine results page, traffic to our websites would decrease and, if we are unable to maintain or increase traffic to our marketplaces, our business and operating results could be adversely affected.

Our ability to generate revenues from our marketplace business depends, in part, on our ability to attract users to our websites. Google, Bing, DuckDuckGo and other internet search engines drive traffic to our websites, including CoStar.com, the LoopNet Network, the Apartments.com Network, our Homes.com and OnTheMarket residential marketplaces, the Land.com Network, Ten-X.com and BizBuySell. For example, when a user enters in a search query for an apartment building name or address into an internet search engine, the internet search engine’s ranking of our Apartments.com or Homes.com webpages will determine how prominently such webpages are displayed on the search engine results page. Our ability to maintain prominent search result rankings and positioning is not entirely within our control. Our competitors’ SEO and SEM efforts may result in webpages from their websites receiving higher rankings than the webpages from our websites. Internet search engines could revise their algorithms and methodologies in ways that would adversely affect our search result rankings. Internet search engine providers could form partnerships or enter into other business relationships with our competitors resulting in competitors’ sites receiving higher search result rankings. Internet search engines are increasingly placing alternative search features (such as featured snippets, local map results, and other immersive experiences) on the search engine results page above or more prominently than search engine results. If our search result rankings are not prominently displayed, traffic to our websites may decline which could slow the growth of our user base. Our websites have experienced fluctuations in search result rankings in the past and we anticipate similar fluctuations will occur in the future. If we experience a material reduction in the number of users directed to our websites through internet search engines or otherwise fail to maintain or increase traffic to our marketplaces, our ability to acquire additional subscribers or advertisers and deliver leads to and retain existing subscribers and advertisers could be adversely affected. As a result, our business, results of operations and financial condition could be adversely affected. Increases in our operating expenses could negatively impact our operating results if we are unable to generate more revenues through increased sales of subscriptions to our marketplace products. Additionally, the methods, including Google Analytics, that we use to measure average monthly unique visitors to our portals may misstate the actual number of unique persons who visit our network of mobile applications and websites for a given month or may differ from the methods used by competitors, which may impact the comparability of unique visitors between companies. For example, starting on July 1, 2024, Universal Analytics (UA), Google’s legacy analytics platform on which we historically relied for calculating monthly average unique visitors was discontinued by Google. Prior to June 1, 2024, we measured average monthly unique visitors for all CoStar Group sites using Google’s Universal Analytics. Beginning June 1, 2024, average monthly unique visitors are measured using Google Analytics 4 (GA4), the replacement for Universal Analytics. Due to the change in methodologies, unique visitors reported prior to June 1,2024 may not provide a meaningful comparison to unique visitors in subsequent periods.

**Item 2.**Unregistered Sales of Equity Securities and Use of Proceeds

The following table is a summary of our repurchases of CoStar Group Shares during each of the three months in the quarter ended September 30, 2024:

ISSUER PURCHASES OF EQUITY SECURITIES

(1) The number of CoStar Group Shares purchased consists of CoStar Group Shares tendered by employees to the Company to satisfy the employees' minimum tax withholding obligations arising as a result of vesting of restricted stock grants under the Company’s 2016 Stock Incentive Plan, as amended, which shares

were purchased by the Company based on their fair market value on the trading day immediately preceding the vesting date. None of these share purchases were part of a publicly announced program to purchase CoStar Group Shares.

**Item 3.**Defaults Upon Senior Securities

None.

**Item 4.**Mine Safety Disclosures

Not applicable.