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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 10-K

Commission File Number 1-13045

IRON MOUNTAIN INCORPORATED

(Exact name of Registrant as Specified in Its Charter)

Delaware

(State or other jurisdiction of incorporation)

85 New Hampshire Avenue, Suite 150

Portsmouth, New Hampshire

(Address of principal executive offices)

23-2588479

(I.R.S. Employer Identification No.)

03801

(Zip Code)

617-535-4766

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ☒

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically, every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer", "accelerated filer", "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. Yes ☒ No ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to § 240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of June 30, 2025, the last business day of the registrant's most recently completed second fiscal quarter, the aggregate market value of the Common Stock of the registrant held by non-affiliates of the registrant was approximately $29.8 billion based on the closing price on the New York Stock Exchange on such date.

Number of shares of the registrant’s Common Stock at February 6, 2026: 295,835,206

DOCUMENTS INCORPORATED BY REFERENCE

Certain information required in Items 10, 11, 12, 13 and 14 of Part III of this Annual Report on Form 10-K (the "Annual Report") is incorporated by reference from our definitive Proxy Statement for our 2026 Annual Meeting of Stockholders (our "Proxy Statement") to be filed with the Securities and Exchange Commission (the "SEC") within 120 days after the close of the fiscal year ended December 31, 2025.

IRON MOUNTAIN INCORPORATED

2025 FORM 10-K ANNUAL REPORT

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References in this Annual Report on Form 10-K for the year ended December 31, 2025 (this "Annual Report") to "the Company", "Iron Mountain", "we", "us" or "our" include Iron Mountain Incorporated, a Delaware corporation, and its predecessor, as applicable, and its consolidated subsidiaries, unless the context indicates otherwise.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

We have made statements in this Annual Report that constitute "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995 and other securities laws. These forward-looking statements concern our current expectations regarding our future results from operations, economic performance, financial condition, goals, strategies, investment objectives, plans and achievements. These forward-looking statements are subject to various known and unknown risks, uncertainties and other factors, and you should not rely upon them except as statements of our present intentions and of our present expectations, which may or may not occur. When we use words such as "believes", "expects", "anticipates", "estimates", "plans", "intends", "pursue", "commits", "will" or similar expressions, we are making forward-looking statements. Although we believe that our forward-looking statements are based on reasonable assumptions, our expected results may not be achieved, and actual results may differ materially from our expectations. In addition, important factors that could cause actual results to differ from expectations include, among others:

• our ability or inability to execute our strategic growth plan, including our ability to invest according to plan, grow our businesses (including through joint ventures or other co-investment vehicles), incorporate alternative technologies (including artificial intelligence ("AI") ) into our business, achieve satisfactory returns on new product offerings, continue our revenue management, expand and manage our global operations, complete acquisitions on satisfactory terms, integrate acquired companies efficiently and transition to more sustainable sources of energy;

• changes in customer preferences and demand for our storage and information management services, including as a result of the shift from paper and tape storage to alternative technologies that require less physical space or services activity;

• the costs of complying with and our ability to comply with laws, regulations and customer requirements, including those relating to data privacy and cybersecurity issues, as well as fire and safety and environmental standards, and regulatory and contractual requirements under government contracts;

• the impact of attacks on our internal information technology ("IT") systems, including the impact of such incidents on our reputation and ability to compete and any litigation or disputes that may arise in connection with such incidents;

• our ability to fund capital expenditures;

• the impact of our distribution requirements on our ability to execute our business plan;

• our ability to remain qualified for taxation as a real estate investment trust for United States federal income tax purposes ("REIT");

• changes in the political and economic environments in the countries in which we operate and changes in the global political climate;

• our ability to raise debt or equity capital and changes in the cost of our debt;

• our ability to comply with our existing debt obligations and restrictions in our debt instruments;

• the impact of service interruptions or equipment damage and the cost of power on our data center operations;

• the cost or potential liabilities associated with real estate necessary for our business;

• unexpected events, including those resulting from climate change or geopolitical events, could disrupt our operations and adversely affect our reputation and results of operations;

• fluctuations in commodity prices;

• competition for customers;

• our ability to attract, develop, and retain key personnel;

• deficiencies in our disclosure controls and procedures or internal control over financial reporting;

• other trends in competitive or economic conditions affecting our financial condition or results of operations not presently contemplated; and

• the other risks described in our periodic reports filed with the SEC, including under the caption "Risk Factors" in Part I, Item 1A of this Annual Report.

Except as required by law, we undertake no obligation to update any forward-looking statements appearing in this report.

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PART I