Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2025

Summary Of Significant Accounting Policies

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

A. CASH AND CASH EQUIVALENTS

Cash and cash equivalents include cash on hand and cash invested in highly liquid short-term securities, which have remaining maturities at the date of purchase of less than 90 days. Cash and cash equivalents are carried at cost, which approximates fair value.

B. ACCOUNTS RECEIVABLE

We maintain an allowance for doubtful accounts and a credit memo reserve for estimated losses resulting from the potential inability of our customers to make required payments and potential disputes regarding billing and service issues. The rollforward of the allowance for doubtful accounts and credit memo reserves for the nine months ended September 30, 2025 is as follows:



Balance as of December 31, 2024	$	86,712
Credit memos charged to revenue	73,715
Allowance for bad debts charged to expense	43,527
Deductions and other(1)	(97,367)
Balance as of September 30, 2025	$	106,587

(1)Primarily consists of the issuance of credit memos, the write-off of accounts receivable and the impact associated with currency translation adjustments.

C. LEASES

We lease facilities for certain warehouses, data centers and office space. We also have land leases, including those on which certain facilities are located.

Operating and financing lease right-of-use assets and lease liabilities as of September 30, 2025 and December 31, 2024 are as follows:


DESCRIPTION	SEPTEMBER 30, 2025		DECEMBER 31, 2024
Assets:
Operating lease right-of-use assets	$	2,455,450	$	2,489,893
Financing lease right-of-use assets, net of accumulated depreciation(1)	462,504		359,265
Liabilities:
Current
Operating lease liabilities	$	326,320	$	315,400
Financing lease liabilities(1)	54,123		128,397
Long-term
Operating lease liabilities	$	2,283,504	$	2,334,826
Financing lease liabilities(1)	461,446		278,444

(1)Financing lease right-of-use assets, current financing lease liabilities and long-term financing lease liabilities are included within Property, plant and equipment, net, Current portion of long-term debt and Long-term debt, net of current portion, respectively, within our Condensed Consolidated Balance Sheets.

The components of the lease expense for the three and nine months ended September 30, 2025 and 2024 are as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
DESCRIPTION	2025		2024		2025		2024
Operating lease cost(1)	$	176,591	$	168,308	$	529,730	$	512,789
Financing lease cost:
Depreciation of financing lease right-of-use assets	$	16,737	$	13,907	$	45,715	$	36,929
Interest expense for financing lease liabilities	6,994		5,593		20,448		16,031

(1)Operating lease cost, the majority of which is included in Cost of sales, includes variable lease costs of $46,221 and $139,887 for the three and nine months ended September 30, 2025, respectively, and $42,785 and $120,473 for the three and nine months ended September 30, 2024, respectively.

Other information: Supplemental cash flow information relating to our leases for the nine months ended September 30, 2025 and 2024 is as follows:


	NINE MONTHS ENDED SEPTEMBER 30,
CASH PAID FOR AMOUNTS INCLUDED IN MEASUREMENT OF LEASE LIABILITIES:	2025		2024
Operating cash flows used in operating leases	$	371,753	$	355,509

Operating cash flows used in financing leases (interest)	20,448		16,031
Financing cash flows used in financing leases	41,478		41,079

NON-CASH ITEMS:
Operating lease modifications and reassessments	$	(10,137)	$	9,536
New operating leases (including acquisitions)	189,005		97,708

D. GOODWILL

Our reporting units as of December 31, 2024 are described in detail in Note 2.l. to Notes to Consolidated Financial Statements included in our Annual Report.

The changes in the carrying value of goodwill attributable to each reportable segment and Corporate and Other (as defined in Note 8) for the nine months ended September 30, 2025 are as follows:


	GLOBAL RIM BUSINESS		GLOBAL DATA CENTER BUSINESS		CORPORATE AND OTHER		TOTAL CONSOLIDATED
Goodwill balance, net of accumulated amortization, as of December 31, 2024	$	3,816,874	$	469,461	$	797,482	$	5,083,817
Tax deductible goodwill acquired during the period	—		—		17,620		17,620

Non-tax deductible goodwill acquired during the period	38,775		—		13,171		51,946

Fair value and other adjustments	—		—		(1,464)		(1,464)
Currency effects	100,136		13,997		3,489		117,622
Goodwill balance, net of accumulated amortization, as of September 30, 2025	$	3,955,785	$	483,458	$	830,298	$	5,269,541
Accumulated goodwill impairment balance as of September 30, 2025	$	132,409	$	—	$	26,011	$	158,420

E. FAIR VALUE MEASUREMENTS

The assets and liabilities carried at fair value and measured on a recurring basis as of September 30, 2025 and December 31, 2024 are as follows:


			FAIR VALUE MEASUREMENTS AS OF SEPTEMBER 30, 2025 USING
DESCRIPTION	TOTAL CARRYING VALUE AS OF SEPTEMBER 30, 2025		QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)		SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)		SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)(2)
Money Market Funds	$	5,125	$	—	$	5,125	$	—
Time Deposits	4,272		—		4,272		—
Trading Securities	7,814		6,010		1,804		—
Derivative Assets	243		—		243		—
Derivative Liabilities	68,230		—		68,230		—
Deferred Purchase Obligations(1)	114,578		—		—		114,578


			FAIR VALUE MEASUREMENTS AS OF DECEMBER 31, 2024 USING
DESCRIPTION	TOTAL CARRYING VALUE AS OF DECEMBER 31, 2024		QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)		SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)		SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)(2)
Money Market Funds	$	2,488	$	—	$	2,488	$	—
Time Deposits	9,612		—		9,612		—
Trading Securities	8,144		6,390		1,754		—
Derivative Assets	28,092		—		28,092		—
Derivative Liabilities	5,326		—		5,326		—
Deferred Purchase Obligations(1)	147,055		—		—		147,055

(1)The balance as of September 30, 2025 primarily relates to the fair value of the deferred purchase obligation associated with the Regency Transaction (as defined in Note 3 to Notes to Consolidated Financial Statements included in our Annual Report). The balance as of December 31, 2024 primarily relates to the fair values of the deferred purchase obligations associated with the Regency Transaction and ITRenew Transaction (as defined in Note 3 to Notes to Consolidated Financial Statements included in our Annual Report).

(2)The following is a rollforward of the Level 3 liabilities presented above for December 31, 2024 through September 30, 2025:



Balance as of December 31, 2024	$	147,055
Additions	16,626
Payments	(49,215)
Other changes, including accretion	112
Balance as of September 30, 2025	$	114,578

The level 3 valuation of the deferred purchase obligation was determined primarily utilizing a Monte-Carlo model which takes into account our forecasted projections as they relate to the underlying performance of the business. The Monte-Carlo simulation model incorporates assumptions as to expected revenue over the achievement period, including adjustments for volatility and timing, as well as discount rates that account for the risk of the arrangement and overall market risks. Any material change to these assumptions may result in a significantly higher or lower fair value of the deferred purchase obligation.

There were no material items that were measured at fair value on a non-recurring basis as of September 30, 2025 and December 31, 2024 other than those disclosed in Note 2.p. to Notes to Consolidated Financial Statements included in our Annual Report

F. ACCUMULATED OTHER COMPREHENSIVE ITEMS, NET

The changes in Accumulated other comprehensive items, net for the three and nine months ended September 30, 2025 and 2024 are as follows:


	THREE MONTHS ENDED SEPTEMBER 30, 2025						THREE MONTHS ENDED SEPTEMBER 30, 2024
	FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS		DERIVATIVE FINANCIAL INSTRUMENTS		TOTAL		FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS		DERIVATIVE FINANCIAL INSTRUMENTS		TOTAL
Beginning of Period	$	(353,742)	$	(9,841)	$	(363,583)	$	(471,935)	$	10,844	$	(461,091)
Other comprehensive (loss) income:
Foreign currency translation and other adjustments	(14,969)		—		(14,969)		106,861		—		106,861
Change in fair value of interest rate swaps	—		(72)		(72)		—		(34,281)		(34,281)

Total other comprehensive (loss) income	(14,969)		(72)		(15,041)		106,861		(34,281)		72,580
End of Period	$	(368,711)	$	(9,913)	$	(378,624)	$	(365,074)	$	(23,437)	$	(388,511)


	NINE MONTHS ENDED SEPTEMBER 30, 2025						NINE MONTHS ENDED SEPTEMBER 30, 2024
	FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS		DERIVATIVE FINANCIAL INSTRUMENTS		TOTAL		FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS		DERIVATIVE FINANCIAL INSTRUMENTS		TOTAL
Beginning of Period	$	(568,129)	$	(1,823)	$	(569,952)	$	(373,628)	$	2,472	$	(371,156)
Other comprehensive income (loss):
Foreign currency translation and other adjustments	199,418		—		199,418		8,554		—		8,554
Change in fair value of interest rate swaps	—		(8,090)		(8,090)		—		(23,381)		(23,381)
Reclassifications from accumulated other comprehensive items, net	—		—		—		—		(2,528)		(2,528)
Total other comprehensive income (loss)	199,418		(8,090)		191,328		8,554		(25,909)		(17,355)
End of Period	$	(368,711)	$	(9,913)	$	(378,624)	$	(365,074)	$	(23,437)	$	(388,511)

G. REVENUES

Certain costs to fulfill or obtain customer contracts, including the costs associated with the initial movement of customer records into physical storage and certain commission expenses, and certain initial direct costs of obtaining data center leases are collectively referred to as "Contract Costs". Contract Costs are primarily made up of Intake Costs and Commissions (each as defined in Note 2.s. to Notes to Consolidated Financial Statements included in our Annual Report). Contract Costs as of September 30, 2025 and December 31, 2024 are as follows:


	SEPTEMBER 30, 2025						DECEMBER 31, 2024
DESCRIPTION	GROSS CARRYING AMOUNT		ACCUMULATED AMORTIZATION		NET CARRYING AMOUNT		GROSS CARRYING AMOUNT		ACCUMULATED AMORTIZATION		NET CARRYING AMOUNT
Intake Costs asset	$	108,962	$	(54,780)	$	54,182	$	89,057	$	(43,783)	$	45,274
Commissions asset	229,940		(101,172)		128,768		200,149		(78,955)		121,194

Deferred revenue liabilities are reflected in our Condensed Consolidated Balance Sheets as follows:


DESCRIPTION	LOCATION IN BALANCE SHEET	SEPTEMBER 30, 2025		DECEMBER 31, 2024(1)
Deferred revenue—Current(2)	Deferred revenue	$	347,018	$	326,882
Deferred revenue—Long-term(3)	Other Long-term Liabilities	142,364		110,601

(1) The beginning balance of current and long-term deferred revenue for the year ended December 31, 2024 was $325,665 and $100,770, respectively.

(2) The current deferred revenue accounted for under Accounting Standards Codification 842, Leases ("ASC 842") is approximately $46,500 and $25,500 as of September 30, 2025 and December 31, 2024, respectively.

(3) The long-term deferred revenue accounted for under ASC 842 is approximately $119,500 and $95,000 as of September 30, 2025 and December 31, 2024, respectively.

DATA CENTER LESSOR CONSIDERATIONS

Our Global Data Center Business features storage rental provided to customers at contractually specified rates over a fixed contractual period, which are accounted for in accordance with ASC 842. Storage rental revenue associated with our Global Data Center Business for the three and nine months ended September 30, 2025 and 2024 is as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025		2024		2025		2024
Storage rental revenue	$	201,383	$	150,796	$	562,607	$	438,221

H. STOCK-BASED COMPENSATION

Our stock-based compensation expense includes the cost of stock options, restricted stock units ("RSUs") and performance units ("PUs") (together, the "Employee Stock-Based Awards").

STOCK-BASED COMPENSATION EXPENSE

Stock-based compensation expense for the Employee Stock-Based Awards for the three and nine months ended September 30, 2025 and 2024 is as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025		2024		2025		2024
Stock-based compensation expense	$	32,147	$	29,563	$	118,595	$	73,491

On March 1, 2025, we granted approximately 83,400 stock options, 497,000 RSUs and 435,100 PUs under the 2014 Plan (as defined in Note 2.t. to Notes to Consolidated Financial Statements included in our Annual Report).

On May 29, 2025, our stockholders approved an amendment to the 2014 Plan, which (i) increases the number of shares of common stock authorized for issuance under the 2014 Plan by 4,600,000, from 20,750,000 to 25,350,000, and (ii) extends the termination date of the 2014 Plan from May 12, 2031 to May 29, 2035.

As of September 30, 2025, unrecognized compensation cost related to the unvested portion of our Employee Stock-Based Awards, inclusive of our estimated achievement of the performance metrics, is $106,527.

I. ACQUISITION AND INTEGRATION COSTS

Acquisition and integration costs represent operating expenditures directly associated with the closing and integration activities of our business acquisitions that have closed, or are highly probable of closing, and include (i) advisory, legal and professional fees to complete business acquisitions and (ii) costs to integrate acquired businesses into our existing operations, including move, severance and system integration costs (collectively, "Acquisition and Integration Costs").

Acquisition and Integration Costs for the three and nine months ended September 30, 2025 and 2024 are as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025		2024		2025		2024
Acquisition and Integration Costs	$	5,402	$	11,262	$	16,040	$	28,573

J. LOSS (GAIN) ON DISPOSAL/WRITE-DOWN OF PROPERTY, PLANT AND EQUIPMENT, NET

Loss (gain) on disposal/write-down of property, plant and equipment, net for the three and nine months ended September 30, 2025 and 2024 is as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025		2024		2025		2024
Loss (gain) on disposal/write-down of property, plant and equipment, net	$	3,366	$	5,091	$	7,975	$	8,270

K. OTHER (INCOME) EXPENSE, NET

Other (income) expense, net for the three and nine months ended September 30, 2025 and 2024 consists of the following:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
DESCRIPTION	2025		2024		2025		2024
Foreign currency transaction (gains) losses, net(1)	$	(7,203)	$	46,657	$	109,615	$	31,291
Debt extinguishment expense	—		5,417		—		5,417
Other, net(2)	3,217		34,288		(3,236)		42,957
Other (Income) Expense, Net	$	(3,986)	$	86,362	$	106,379	$	79,665

(1)The losses for the nine months ended September 30, 2025 and the three and nine months ended September 30, 2024 primarily consist of the impact of changes in the exchange rate of the British pound sterling and the Euro against the United States dollar on our intercompany balances with and between certain of our subsidiaries.

(2)Other, net for the three and nine months ended September 30, 2024 primarily consists of approximately $29,200 in charges associated with the agreement to purchase the remaining interest in the Web Werks JV (as defined in Note 3 to Notes to Consolidated Financial Statements included in our Annual Report) as well as losses on our equity method investments and the change in value of our deferred purchase obligations.

L. INCOME TAXES

We provide for income taxes during interim periods based on our estimate of the effective tax rate for the year. Our effective tax rates for the three and nine months ended September 30, 2025 and 2024 are as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025(1)		2024(3)		2025(2)		2024(3)
Effective Tax Rate	16.1	%	58.3	%	44.7	%	35.2	%

(1)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three months ended September 30, 2025 were the benefits derived from the dividends paid deduction, as well as the differences in the tax rates to which our foreign earnings are subject.

(2)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the nine months ended September 30, 2025 were the (i) lack of tax benefits recognized for the foreign exchange losses we recorded in Other expense (income), net, during the period, (ii) lack of tax benefits recognized for the year to date ordinary losses of certain entities, (iii) disallowed interest expenses of certain entities and (iv) differences in the tax rates to which our foreign earnings are subject, partially offset by (v) benefits derived from the dividends paid deduction.

(3)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three and nine months ended September 30, 2024 were the (i) lack of tax benefits recognized for the year to date ordinary losses of certain entities, (ii) benefits derived from the dividends paid deduction and (iii) differences in the tax rates to which our foreign earnings are subject. In addition, we recorded gains and losses in Other expense (income), net during the period, for which there was no tax impact.

On July 4, 2025, President Trump signed into law the reconciliation bill, commonly referred to as the One Big Beautiful Bill Act ("OBBBA"). The OBBBA introduces several changes to U.S. federal income tax law, such as suspending the capitalization and amortization of domestic research and development expenditures and reinstating bonus depreciation. It also modifies the deductions available for global intangible low-taxed income from non-U.S. subsidiaries and changes the limitations on deductible interest. Under the current law, not more than 20% of the value of a REIT’s total assets at the end of any quarter could be represented by securities of one or more taxable REIT subsidiaries; the OBBBA increases this threshold to 25% effective January 1, 2026. The effective dates of the OBBBA provisions range from 2025 through 2027. We do not expect the OBBBA provisions to have a material impact on our consolidated financial statements.

In addition, in connection with the removal of the proposed section 899, "Enforcement of Remedies Against Unfair Foreign Taxes," from the OBBBA, the U.S. Treasury Department reached an agreement with the six other G7 countries (Canada, France, Germany, Italy, Japan and the UK) under which U.S. companies will be excluded from the imposition of any Pillar Two Income Inclusion Rule or Undertaxed Profits Rule taxes. We will continue to monitor the global legislative actions as well as administrative guidance related to Pillar Two for potential impacts, which are not expected to have a material impact on our consolidated financial statements.

M. INCOME (LOSS) PER SHARE—BASIC AND DILUTED

The calculations of basic and diluted income (loss) per share for the three and nine months ended September 30, 2025 and 2024 are as follows:


	THREE MONTHS ENDED SEPTEMBER 30,				NINE MONTHS ENDED SEPTEMBER 30,
	2025		2024		2025		2024
Net Income (Loss)	$	86,241	$	(33,665)	$	59,134	$	77,981
Less: Net Income (Loss) Attributable to Noncontrolling Interests	1,951		(45)		3,813		1,757
Net Income (Loss) Attributable to Iron Mountain Incorporated (utilized in numerator of Earnings Per Share calculation)	$	84,290	$	(33,620)	$	55,321	$	76,224
Weighted-average shares—basic	295,771,000		293,603,000		295,214,000		293,229,000
Effect of dilutive potential stock options	1,898,000		—		2,020,000		2,143,000
Effect of dilutive potential RSUs and PUs	312,000		—		394,000		540,000
Weighted-average shares—diluted	297,981,000		293,603,000		297,628,000		295,912,000
Net Income (Loss) Per Share Attributable to Iron Mountain Incorporated:
Basic	$	0.28	$	(0.11)	$	0.19	$	0.26
Diluted	$	0.28	$	(0.11)	$	0.19	$	0.26
Antidilutive stock options, RSUs and PUs excluded from the calculation	102,248		3,083,222		112,101		293,457

IRON MOUNTAIN INC 10-Q