AMERICAN TOWER CORP MA

For a discussion of our 2022 Liquidity and Capital Resources, including a discussion of cash flows for the fiscal year ended December 31, 2022 compared to the fiscal year ended December 31, 2021, refer to Part I, Item 7 of the 2022 Form 10-K.

Overview

During the year ended December 31, 2023, we increased our financial flexibility and our ability to grow our business while maintaining our long-term financial policies. Our significant 2023 financing transactions included:

•Redemption of our 3.50% senior unsecured notes due 2023 (the “3.50% Notes”) and our 3.000% senior unsecured notes due 2023 (the “3.000% Notes”) upon their maturity;

•Registered public offering in an aggregate amount of $5.7 billion, including 1.1 billion EUR, of senior unsecured notes with maturities ranging from 2027 to 2033;

•Securitization transactions, including the repayment of $1.3 billion aggregate principal amount outstanding under our Secured Tower Revenue Securities, Series 2013-2A due 2023 (the “Series 2013-2A Securities”) and the issuance of $1.3 billion aggregate principal amount of the Series 2023-1A Securities (as defined below);

•Repayment of $1.5 billion under our $1.5 billion unsecured term loan entered into in December 2021 (the “2021 USD Two Year Delayed Draw Term Loan”); and

•Amendment of the 2021 Multicurrency Credit Facility, the 2021 Credit Facility and the 2021 Term Loan (each as defined below) to, among other things, (i) extend the maturity dates under each of the 2021 Multicurrency Credit Facility and the 2021 Credit Facility and (ii) adopt an Adjusted Term SOFR (as defined in the amendment agreements) pricing benchmark.

The following table summarizes our liquidity as of December 31, 2023 (in millions):

Subsequent to December 31, 2023, we made additional net borrowings of $485.0 million under the 2021 Credit Facility (as defined below) and $1.8 billion under the 2021 Multicurrency Credit Facility (as defined below). The borrowings were used to repay existing indebtedness and for general corporate purposes.

On January 4, 2024, we entered into an agreement with DIT for the Pending ATC TIPL Transaction, pursuant to which DIT will acquire a 100% ownership interest in ATC TIPL. We will retain the full economic benefit associated with the VIL OCDs and rights to payments on certain existing customer receivables. Subject to certain pre-closing terms, total aggregate consideration would potentially represent up to 210 billion INR (approximately $2.5 billion), including the value of the VIL OCDs, payments on certain existing customer receivables, the repayment of existing intercompany debt and the repayment, or assumption, of our existing term loan in India, by DIT. The Pending ATC TIPL Transaction is expected to close in the second half of 2024, subject to customary closing conditions, including government and regulatory approval. We expect to use the proceeds from the Pending ATC TIPL Transaction to repay existing indebtedness, including under the 2021 Multicurrency Credit Facility and the 2021 Credit Facility.

Summary cash flow information is set forth below for the years ended December 31, (in millions):

We use our cash flows to fund our operations and investments in our business, including maintenance and improvements, communications site and data center construction, managed network installations and acquisitions. Additionally, we use our cash flows to make distributions, including distributions of our REIT taxable income to maintain our qualification for taxation as a REIT under the Code. We may also periodically repay or repurchase our existing indebtedness or equity. We typically fund our international expansion efforts primarily through a combination of cash on hand, intercompany debt and equity contributions.

On an on-going basis, we also perform a comprehensive assessment of our global operations to ensure our portfolio is positioned to drive sustained growth and achieve our risk-adjusted return objectives. This assessment may result in our decision to divest a portion, or all, of certain assets, including our Mexico fiber and Poland businesses in 2023, and our signed agreement in January 2024 with DIT for the Pending ATC TIPL Transaction, and repurpose proceeds, and potential future capital, to other capital priorities.

As of December 31, 2023, we had total outstanding indebtedness of $39.2 billion, with a current portion of $3.2 billion. During the year ended December 31, 2023, we generated sufficient cash flow from operations, together with borrowings under our credit facilities, proceeds from our equity and debt issuances and cash on hand, to fund our acquisitions, capital expenditures and debt service obligations, as well as our required distributions. We believe the cash generated by operating activities during the year ending December 31, 2024, together with our borrowing capacity under our credit facilities, will suffice to fund our required distributions, capital expenditures, debt service obligations (interest and principal repayments) and signed acquisitions.

As of December 31, 2023, we had $1.6 billion of cash and cash equivalents held by our foreign subsidiaries. As of December 31, 2023, we had $223.6 million of cash and cash equivalents held by our joint ventures, of which $196.6 million was held by our foreign joint ventures. While certain subsidiaries may pay us interest or principal on intercompany debt, we have historically not repatriated earnings from our foreign subsidiaries. However, in the event that we do repatriate any funds, we may be required to accrue and pay certain taxes.

Cash Flows from Operating Activities

For the year ended December 31, 2023, cash provided by operating activities increased $1.0 billion as compared to the year ended December 31, 2022. The primary factors that impacted cash provided by operating activities as compared to the year ended December 31, 2022, include:

•Changes in unearned revenue, as the prior year ended December 31, 2022 included the impact of advance payments from a customer during the year ended December 31, 2021; and

•An increase in our property segment operating profit of $510.9 million;

•Partially offset by an increase of approximately $171.4 million in cash paid for interest.

Cash Flows from Investing Activities

Our significant investing activities during the year ended December 31, 2023 are highlighted below:

•We spent approximately $168.0 million for acquisitions, including payments made for acquisitions completed in 2022.

•We spent $1.8 billion for capital expenditures, as follows (in millions):

(1)Includes the construction of 3,198 communications sites globally and approximately $395 million of spend related to data center assets.

(2)Includes $38.7 million of perpetual land easement payments reported in Deferred financing costs and other financing activities in the cash flows from financing activities in our consolidated statements of cash flows.

(3)Includes $6.2 million of finance lease payments reported in Repayments of notes payable, credit facilities, term loans, senior notes, secured debt and finance leases in the cash flows from financing activities in our consolidated statements of cash flows.

(4)Net of purchase credits of $13.2 million on certain assets, which are reported in investing activities in our consolidated statements of cash flows.

We plan to continue to allocate our available capital, after satisfying our distribution requirements, among investment alternatives that meet our return on investment criteria, while maintaining our commitment to our long-term financial policies. Accordingly, we expect to continue to deploy capital through our annual capital expenditure program, including land purchases and new site and data center facility construction, and through acquisitions. We also regularly review our portfolios as to capital expenditures required to upgrade our infrastructure to our structural standards or address capacity, structural or permitting issues.

We expect that our 2024 total capital expenditures will be as follows (in millions):

(1) Includes the construction of approximately 2,500 to 3,500 communications sites globally and approximately $450 million of anticipated spend related to data center assets.

Cash Flows from Financing Activities

Our significant financing activities were as follows (in millions):

(1)For the year ended December 31, 2022, included payment in full of $875.0 million aggregate principal amount and a fair value adjustment of $80.1 million of debt assumed in connection with the CoreSite Acquisition.

(2)For the year ended December 31, 2022, included $3.1 billion of contributions received in connection with Stonepeak’s acquisition of a noncontrolling ownership interest in our U.S. data center business.

Securitizations

Repayment of Series 2013-2A Securities—On the March 2023 repayment date, we repaid the entire $1.3 billion aggregate principal amount outstanding under the Series 2013-2A Securities, pursuant to the terms of the agreements governing such securities. The repayment was funded with proceeds from the 2023 Securitization (as defined below).

Secured Tower Revenue Securities, Series 2023-1, Subclass A and Series 2023-1, Subclass R—On March 13, 2023, we completed a securitization transaction (the “2023 Securitization”), in which American Tower Trust I (the “Trust”) issued $1.3 billion aggregate principal amount of Secured Tower Revenue Securities, Series 2023-1, Subclass A (the “Series 2023-1A Securities”). To satisfy the applicable risk retention requirements of Regulation RR promulgated under the Securities Exchange Act of 1934, as amended (the “Exchange Act” and, such requirements, the “Risk Retention Rules”), the Trust issued, and one of our affiliates purchased, $68.5 million aggregate principal amount of Secured Tower Revenue Securities, Series 2023-1, Subclass R (the “Series 2023-1R Securities” and, together with the Series 2023-1A Securities, the “2023 Securities”) to retain an “eligible horizontal residual interest” (as defined in the Risk Retention Rules) in an amount equal to at least 5% of the fair value of the 2023 Securities.

The assets of the Trust consist of a nonrecourse loan broken into components or “componentized” (the “Loan”), which also secures each of (i) the Secured Tower Revenue Securities, Series 2018-1, Subclass A (the “Series 2018-1A Securities”) and (ii) the Secured Tower Revenue Securities, Series 2018-1, Subclass R (the “Series 2018-1R Securities” and, together with the Series 2018-1A Securities, the “2018 Securities”) issued in a securitization transaction in March 2018 (the “2018 Securitization” and, together with the 2023 Securitization, the “Trust Securitizations”) made by the Trust to American Tower Asset Sub, LLC and American Tower Asset Sub II, LLC (together, the “AMT Asset Subs”).

The AMT Asset Subs are jointly and severally liable under the Loan, which is secured primarily by mortgages on the AMT Asset Subs’ interests in 5,034 broadcast and wireless communications towers and related assets (the “Trust Sites”).

The 2023 Securities correspond to components of the Loan made to the AMT Asset Subs pursuant to the Second Supplement and Amendment dated as of March 13, 2023 (the “2023 Supplement”) to the Second Amended and Restated Loan and Security Agreement dated as of March 29, 2018 (the “Loan Agreement,” which continues to govern the 2018 Securities, and collectively, the “Trust Loan Agreement”).

The 2023 Securities (a) represent a pass-through interest in the components of the Loan corresponding to the 2023 Securities and (b) have an expected life of approximately five years with a final repayment date in March 2053. The Series 2023-1A Securities and the Series 2023-1R Securities have interest rates of 5.490% and 5.735%, respectively.

The debt service on the Loan will be paid solely from the cash flows generated from the operation of the Trust Sites held by the AMT Asset Subs. The AMT Asset Subs are required to make monthly payments of interest on the Loan. Subject to certain limited exceptions described below, no payments of principal will be required to be made on the components of the Loan corresponding to the 2023 Securities prior to the monthly payment date in March 2028, which is the anticipated repayment date for such components.

The AMT Asset Subs may prepay the Loan at any time, provided that prepayment is accompanied by applicable prepayment consideration. If the prepayment occurs within twelve months of the anticipated repayment date for the 2023 Securities, no prepayment consideration is due. The entire unpaid principal balance of the components of the Loan corresponding to the 2023 Securities will be due in March 2053.

Senior Notes

Repayments of Senior Notes

Repayment of 3.50% Senior Notes—On January 31, 2023, we repaid $1.0 billion aggregate principal amount of our 3.50% Notes upon their maturity. The 3.50% Notes were repaid using borrowings under the 2021 Credit Facility. Upon completion of the repayment, none of the 3.50% Notes remained outstanding.

Repayment of 3.000% Senior Notes—On June 15, 2023, we repaid $700.0 million aggregate principal amount of our 3.000% Notes upon their maturity. The 3.000% Notes were repaid using borrowings under the 2021 Credit Facility. Upon completion of the repayment, none of the 3.000% Notes remained outstanding.

Repayment of 0.600% Senior Notes—On January 12, 2024, we repaid $500.0 million aggregate principal amount of our 0.600% senior unsecured notes due 2024 (the “0.600% Notes”) upon their maturity. The 0.600% Notes were repaid using borrowings under the 2021 Multicurrency Credit Facility. Upon completion of the repayment, none of the 0.600% Notes remained outstanding.

Repayment of 5.00% Senior Notes—On February 14, 2024, we repaid $1.0 billion aggregate principal amount of our 5.00% senior unsecured notes due 2024 (the “5.00% Notes”) upon their maturity. The 5.00% Notes were repaid using borrowings under the 2021 Multicurrency Credit Facility. Upon completion of the repayment, none of the 5.00% Notes remained outstanding.

Offerings of Senior Notes

5.500% Senior Notes and 5.650% Senior Notes Offering—On March 3, 2023, we completed a registered public offering of $700.0 million aggregate principal amount of 5.500% senior unsecured notes due 2028 (the “5.500% Notes”) and $800.0 million aggregate principal amount of 5.650% senior unsecured notes due 2033 (the “5.650% Notes”). The net proceeds from this offering were approximately $1,480.9 million, after deducting commissions and estimated expenses, which we used to repay existing indebtedness under the 2021 Multicurrency Credit Facility and the 2021 Credit Facility.

4.125% Senior Notes and 4.625% Senior Notes Offering—On May 16, 2023, we completed a registered public offering of 600.0 million EUR ($652.1 million at the date of issuance) aggregate principal amount of 4.125% senior unsecured notes due 2027 (the “4.125% Notes”) and 500.0 million EUR ($543.4 million at the date of issuance) aggregate principal amount of

4.625% senior unsecured notes due 2031 (the “4.625% Notes”). The net proceeds from this offering were approximately 1,089.5 million EUR (approximately $1,184.1 million at the date of issuance), after deducting commissions and estimated expenses, which we used to repay existing indebtedness under the 2021 Multicurrency Credit Facility and the 2021 Credit Facility.

5.250% Senior Notes and 5.550% Senior Notes Offering—On May 25, 2023, we completed a registered public offering of $650.0 million aggregate principal amount of 5.250% senior unsecured notes due 2028 (the “5.250% Notes”) and $850.0 million aggregate principal amount of 5.550% senior unsecured notes due 2033 (the “5.550% Notes”). The net proceeds from this offering were approximately $1,481.9 million, after deducting commissions and estimated expenses, which we used to repay existing indebtedness under the 2021 Multicurrency Credit Facility.

5.800% Senior Notes and 5.900% Senior Notes Offering—On September 15, 2023, we completed a registered public offering of $750.0 million aggregate principal amount of 5.800% senior unsecured notes due 2028 (the “5.800% Notes”) and $750.0 million aggregate principal amount of 5.900% senior unsecured notes due 2033 (the “5.900% Notes” and, together with the 5.500% Notes, the 5.650% Notes, the 4.125% Notes, the 4.625% Notes, the 5.250% Notes, the 5.550% Notes and the 5.800% Notes, the “2023 Notes”). The net proceeds from this offering were approximately $1,482.8 million, after deducting commissions and estimated expenses, which we used to repay existing indebtedness under the 2021 Multicurrency Credit Facility.

The key terms of the 2023 Notes are as follows:

(1)Accrued and unpaid interest on U.S. Dollar (“USD”) denominated notes is payable in USD semi-annually in arrears and will be computed from the issue date on the basis of a 360-day year comprised of twelve 30-day months. Interest on EUR denominated notes is payable in EUR annually in arrears and will be computed on the basis of the actual number of days in the period for which interest is being calculated and the actual number of days from and including the last date on which interest was paid on the notes, beginning on the issue date.

(2)We may redeem the 2023 Notes at any time, in whole or in part, at a redemption price equal to 100% of the principal amount of the 2023 Notes plus a make-whole premium, together with accrued interest to the redemption date. If we redeem the 2023 Notes on or after the par call date, we will not be required to pay a make-whole premium.

(3)The 4.125% Notes and the 4.625% Notes are denominated in EUR; dollar amounts represent the aggregate principal amount at the issuance date.

If we undergo a change of control and corresponding ratings decline, each as defined in the applicable supplemental indenture for the 2023 Notes, we may be required to repurchase all of the 2023 Notes at a purchase price equal to 101% of the principal amount of those 2023 Notes, plus accrued and unpaid interest (including additional interest, if any), up to but not including the repurchase date. The 2023 Notes rank equally with all of our other senior unsecured debt and are structurally subordinated to all existing and future indebtedness and other obligations of our subsidiaries.

Each applicable supplemental indenture contains certain covenants that restrict our ability to merge, consolidate or sell assets and our (together with our subsidiaries’) ability to incur liens. These covenants are subject to a number of exceptions, including that we and our subsidiaries may incur certain liens on assets, mortgages or other liens securing indebtedness if the aggregate amount of indebtedness secured by such liens does not exceed 3.5x Adjusted EBITDA, as defined in the applicable supplemental indenture.

Bank Facilities

Amendments to Bank Facilities—On June 29, 2023, we amended our (i) $6.0 billion senior unsecured multicurrency revolving credit facility, as previously amended and restated on December 8, 2021 (the “2021 Multicurrency Credit Facility”), (ii) $4.0 billion senior unsecured revolving credit facility, as previously amended and restated on December 8, 2021, (the “2021 Credit Facility”) and (iii) $1.0 billion unsecured term loan, as previously amended and restated on December 8, 2021, (the “2021 Term Loan”).

These amendments, among other things,

i. extend the maturity dates of the 2021 Multicurrency Credit Facility and the 2021 Credit Facility to July 1, 2026 and July 1, 2028, respectively;

ii. commemorate commitments under the 2021 Multicurrency Credit Facility and the 2021 Credit Facility of $6.0 billion and $4.0 billion, respectively; and

iii. replace the London Interbank Offered Rate (“LIBOR”) pricing benchmark with an Adjusted Term Secured Overnight Financing Reserve (“SOFR”) pricing benchmark.

2021 Multicurrency Credit Facility—As of December 31, 2023, we had the ability to borrow up to $6.0 billion under the 2021 Multicurrency Credit Facility, which includes a $3.5 billion sublimit for multicurrency borrowings, a $200.0 million sublimit for letters of credit and a $50.0 million sublimit for swingline loans. During the year ended December 31, 2023, we borrowed an aggregate of $3.0 billion and repaid an aggregate of $6.1 billion, including 842.6 million EUR ($919.1 million as of the repayment date), of revolving indebtedness under the 2021 Multicurrency Credit Facility. We used the borrowings to repay outstanding indebtedness, including the 2021 USD Two Year Delayed Draw Term Loan, and for general corporate purposes.

2021 Credit Facility—As of December 31, 2023, we had the ability to borrow up to $4.0 billion under the 2021 Credit Facility, which includes a $2.5 billion sublimit for multicurrency borrowings, $200.0 million sublimit for letters of credit and a $50.0 million sublimit for swingline loans. During the year ended December 31, 2023, we borrowed an aggregate of $3.1 billion and repaid an aggregate of $2.6 billion of revolving indebtedness under the 2021 Credit Facility. We used the borrowings to repay outstanding indebtedness, including the 3.50% Notes and the 3.000% Notes, and for general corporate purposes.

Repayment of 2021 USD Two Year Delayed Draw Term Loan—On June 27, 2023, we repaid all amounts outstanding under the 2021 USD Two Year Delayed Draw Term Loan with borrowings under the 2021 Multicurrency Credit Facility.

As of December 31, 2023, the key terms under the 2021 Multicurrency Credit Facility, the 2021 Credit Facility, the 2021 Term Loan and our 825.0 million EUR unsecured term loan, as amended in December 2021 (the “2021 EUR Three Year Delayed Draw Term Loan”) were as follows:

(1)Represents interest rate above: (a) SOFR for SOFR based borrowings, (b) Euro Interbank Offer Rate (“EURIBOR”) for EURIBOR based borrowings and (c) the defined base rate for base rate borrowings, in each case based on our debt ratings.

(2)Currently borrowed at SOFR for USD denominated borrowings and at EURIBOR for EUR denominated borrowings.

(3)Subject to two optional renewal periods.

(4)Currently borrowed at SOFR.

(5)Currently borrowed at EURIBOR.

We must pay a quarterly commitment fee on the undrawn portion of each of the 2021 Multicurrency Credit Facility and the 2021 Credit Facility. The commitment fee for the 2021 Multicurrency Credit Facility and the 2021 Credit Facility ranges from 0.080% to 0.200% per annum, based upon our debt ratings, and is currently 0.110%.

The 2021 Multicurrency Credit Facility, the 2021 Credit Facility, the 2021 Term Loan and the 2021 EUR Three Year Delayed Draw Term Loan and the associated loan agreements (the “Bank Loan Agreements”) do not require amortization of principal and may be paid prior to maturity in whole or in part at our option without penalty or premium. We have the option of choosing either a defined base rate, SOFR or EURIBOR as the applicable base rate for borrowings under these bank facilities.

Each Bank Loan Agreement contains certain reporting, information, financial and operating covenants and other restrictions (including limitations on additional debt, guaranties, sales of assets and liens) with which we must comply. Failure to comply with the financial and operating covenants of the loan agreements could not only prevent us from being able to borrow additional funds under the revolving credit facilities, but may constitute a default, which could result in, among other things, the amounts outstanding under the applicable agreement, including all accrued interest and unpaid fees, becoming immediately due and payable.

India Term Loan—On February 16, 2023, we entered into a 12.0 billion INR (approximately $145.1 million at the date of signing) unsecured term loan with a maturity date that is one year from the date of the first draw thereunder (the “India Term Loan”). On February 17, 2023, we borrowed 10.0 billion INR (approximately $120.7 million at the date of borrowing) under the India Term Loan. The India Term Loan bears interest at the three month treasury bill rate as announced by the Financial Benchmarks India Private Limited at the time of borrowing plus a margin of 1.95%. Any outstanding principal and accrued but unpaid interest will be due and payable in full at maturity. The India Term Loan does not require amortization of principal and may be paid prior to maturity in whole or in part at our option without penalty or premium. In January 2024, we amended the India Term Loan to extend the maturity date to December 31, 2024.

India Working Capital Facilities—The working capital facilities bear interest at rates that consist of the applicable bank’s Marginal Cost of Funds based Lending Rate or Market Benchmark (as defined in the applicable agreement), plus a spread. Generally, the working capital facilities are payable on demand prior to maturity. During the year ended December 31, 2023, we increased the borrowing capacity of our working capital facilities in India by 2.8 billion INR (approximately $33.7 million). During the year ended December 31, 2023, we did not borrow under these facilities.

Amounts outstanding and key terms of the India credit facilities consisted of the following as of December 31, 2023 (in millions, except percentages):

(1) 10.7 billion INR ($128.7 million) of borrowing capacity as of December 31, 2023. We have 0.2 billion INR (approximately $2.7 million) of bank guarantees outstanding included within the overall borrowing capacity.

Stock Repurchase Programs—In March 2011, our Board approved a stock repurchase program, pursuant to which we are authorized to repurchase up to $1.5 billion of our common stock (the “2011 Buyback”). In December 2017, our Board approved an additional stock repurchase program, pursuant to which we are authorized to repurchase up to $2.0 billion of our common stock (the “2017 Buyback,” and, together with the 2011 Buyback, the “Buyback Programs”).

During the year ended December 31, 2023, there were no repurchases under either of the Buyback Programs.

Under each program, we are authorized to purchase shares from time to time through open market purchases or in privately negotiated transactions not to exceed market prices and subject to market conditions and other factors. With respect to open market purchases, we may use plans adopted in accordance with Rule 10b5-1 under the Exchange Act in accordance with securities laws and other legal requirements, which allows us to repurchase shares during periods when we may otherwise be prevented from doing so under insider trading laws or because of self-imposed trading blackout periods. These programs may be discontinued at any time.

We have repurchased a total of 14.5 million shares of our common stock under the 2011 Buyback for an aggregate of $1.5 billion, including commissions and fees. We expect to continue managing the pacing of the remaining approximately $2.0 billion under the Buyback Programs in response to general market conditions and other relevant factors. We expect to fund any further repurchases of our common stock through a combination of cash on hand, cash generated by operations and borrowings under our credit facilities. Repurchases under the Buyback Programs are subject to, among other things, us having available cash to fund the repurchases.

Sales of Equity Securities—We receive proceeds from sales of our equity securities pursuant to our employee stock purchase plan (the “ESPP”) and upon exercise of stock options granted under our equity incentive plan, as amended (the “2007 Plan”). During the year ended December 31, 2023, we received an aggregate of $22.1 million in proceeds upon exercises of stock options and sales pursuant to the ESPP.

Future Financing Transactions—We regularly consider various options to obtain financing and access the capital markets, subject to market conditions, to meet our funding needs. Such capital raising alternatives, in addition to those noted above, may include amendments and extensions of our bank facilities, entry into new bank facilities, transactions with private equity funds or partnerships, additional senior note and equity offerings and securitization transactions. No assurance can be given as to whether any such financing transactions will be completed or as to the timing or terms thereof.

Distributions—As a REIT, we must annually distribute to our stockholders an amount equal to at least 90% of our REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain). Generally, we have distributed, and expect to continue to distribute, all or substantially all of our REIT taxable income after taking into consideration our utilization of NOLs. We have distributed an aggregate of approximately $17.5 billion to our common stockholders, including the dividend paid in February 2024, primarily classified as ordinary income that may be treated as qualified REIT dividends under Section 199A of the Code for taxable years beginning before 2026.

During the year ended December 31, 2023, we paid $6.31 per share, or $2.9 billion, to our common stockholders of record. In addition, we declared a distribution of $1.70 per share, or $792.7 million, paid on February 1, 2024 to our common stockholders of record at the close of business on December 28, 2023.

We accrue distributions on unvested restricted stock units, which are payable upon vesting. The amount accrued for distributions payable related to unvested restricted stock units was $21.5 million and $17.0 million as of December 31, 2023 and 2022, respectively. During the year ended December 31, 2023, we paid $9.0 million of distributions upon the vesting of restricted stock units.

The amount, timing and frequency of future distributions will be at the sole discretion of our Board and will depend on various factors, a number of which may be beyond our control, including our financial condition and operating cash flows, the amount required to maintain our qualification for taxation as a REIT and reduce any income and excise taxes that we otherwise would be required to pay, limitations on distributions in our existing and future debt and preferred equity instruments, our ability to utilize NOLs to offset our distribution requirements, limitations on our ability to fund distributions using cash generated through our TRSs and other factors that our Board may deem relevant.

For more details on the cash distributions paid to our common stockholders during the year ended December 31, 2023, see note 14 to our consolidated financial statements included in this Annual Report.

Material Cash Requirements—The following table summarizes material cash requirements from known contractual and other obligations as of December 31, 2023 (in millions):

(1) Includes aggregate principal maturities of long-term debt, including finance lease obligations (see note 8 to our consolidated financial statements included in this Annual Report).

(2) Includes payments under non-cancellable initial terms, as well as payments for certain renewal periods at our option, which we expect to renew because failure to do so could result in a loss of the applicable communications sites and related revenues from tenant leases (see note 4 to our consolidated financial statements included in this Annual Report).

Distributions—We expect that our 2024 total distributions declared to our common stockholders will be $3.0 billion. The amount, timing and frequency of future distributions will be at the sole discretion of our Board.

Asset Retirement Obligations—We are required to remove our assets and remediate the leased sites upon which certain of our assets are located. As of December 31, 2023, the estimated undiscounted future cash outlay for asset retirement obligations was $4.0 billion.

Factors Affecting Sources of Liquidity

Our liquidity depends on our ability to generate cash flow from operating activities, borrow funds under our credit facilities and maintain compliance with the contractual agreements governing our indebtedness. We believe that the debt agreements discussed below represent our material debt agreements that contain covenants, our compliance with which would be material to an investor’s understanding of our financial results and the impact of those results on our liquidity.

Internally Generated Funds—Because the majority of our customer leases are multiyear contracts, a significant majority of the revenues generated by our property operations as of the end of 2023 is recurring revenue that we should continue to receive in future periods. Accordingly, a key factor affecting our ability to generate cash flow from operating activities is to maintain this recurring revenue and to convert it into operating profit by minimizing operating costs and fully achieving our operating efficiencies. In addition, our ability to increase cash flow from operating activities depends upon the demand for our communications infrastructure and our related services and our ability to increase the utilization of our existing communications infrastructure.

Restrictions Under Loan Agreements Relating to Our Credit Facilities—Each Bank Loan Agreement contains certain financial and operating covenants and other restrictions applicable to us and our subsidiaries that are not designated as unrestricted subsidiaries on a consolidated basis. These restrictions include limitations on additional debt, distributions and dividends, guaranties, sales of assets and liens. The Bank Loan Agreements also contain covenants that establish financial tests with which we and our restricted subsidiaries must comply related to total leverage and senior secured leverage, as set forth in the table below. As of December 31, 2023, we were in compliance with each of these covenants.

(1) Each component of the ratio as defined in the applicable loan agreement.

(2) Assumes no change to Adjusted EBITDA.

(3) Assumes no change to our debt levels.

(4) Effectively, however, additional Senior Secured Debt under this ratio would be limited to the capacity under the Consolidated Total Leverage Ratio.

The Bank Loan Agreements also contain reporting and information covenants that require us to provide financial and operating information to the lenders within certain time periods. If we are unable to provide the required information on a timely basis, we would be in breach of these covenants.

Failure to comply with the financial maintenance tests and certain other covenants of the Bank Loan Agreements could not only prevent us from being able to borrow additional funds under the revolving credit facilities, but may also constitute a default under these credit facilities, which could result in, among other things, the amounts outstanding, including all accrued interest and unpaid fees, becoming immediately due and payable. If this were to occur, we may not have sufficient cash on hand to repay such indebtedness. The key factors affecting our ability to comply with the debt covenants described above are our financial performance relative to the financial maintenance tests defined in the Bank Loan Agreements and our ability to fund our debt service obligations. Based upon our current expectations, we believe our operating results during the next 12 months will be sufficient to comply with these covenants.

Restrictions Under Agreements Relating to the 2015 Securitization and the Trust Securitizations—The indenture and related supplemental indenture governing the American Tower Secured Revenue Notes, Series 2015-2, Class A (the “Series 2015-2 Notes”) issued by GTP Acquisition Partners I, LLC (“GTP Acquisition Partners”) in the 2015 Securitization and the Trust Loan Agreement (collectively, the “Securitization Loan Agreements”) include certain financial ratios and operating covenants and other restrictions customary for transactions subject to rated securitizations. Among other things, GTP Acquisition Partners and the AMT Asset Subs are prohibited from incurring other indebtedness for borrowed money or further encumbering their assets, subject to customary carve-outs for ordinary course trade payables and permitted encumbrances (as defined in the applicable agreements).

Under the Securitization Loan Agreements, amounts due will be paid from the cash flows generated by the assets securing the Series 2015-2 Notes or the assets securing the Loan, as applicable, which must be deposited into certain reserve accounts, and thereafter distributed, solely pursuant to the terms of the applicable agreement. On a monthly basis, after paying all required amounts under the applicable agreement, subject to the conditions described in the table below, the excess cash flows generated from the operation of these assets are released to GTP Acquisition Partners or the AMT Asset Subs, as applicable, which can then be distributed to us for use. As of December 31, 2023, $76.3 million held in such reserve accounts was classified as restricted cash.

Certain information with respect to the 2015 Securitization and the Trust Securitizations is set forth below. The debt service coverage ratio (“DSCR”) is generally calculated as the ratio of the net cash flow (as defined in the applicable agreement) to the amount of interest, servicing fees and trustee fees required to be paid over the succeeding 12 months on the principal amount of the Series 2015-2 Notes or the Loan, as applicable, that will be outstanding on the payment date following such date of determination.

(1) Based on the net cash flow of the applicable issuer or borrower as of December 31, 2023 and the expenses payable over the next 12 months on the Series 2015-2 Notes or the Loan, as applicable.

(2) If the DSCR were equal to or below 1.30x (the “Cash Trap DSCR”) for any quarter, all cash flow in excess of amounts required to make debt service payments, fund required reserves, pay management fees and budgeted operating expenses and make other payments required under the applicable transaction documents, referred to as excess cash flow, will be deposited into a reserve account (the “Cash Trap Reserve Account”) instead of being released to the applicable issuer or borrower. Once triggered, a Cash Trap DSCR condition continues to exist until the DSCR exceeds the Cash Trap DSCR for two consecutive calendar quarters. Additionally, if the borrower under the 2023 Securitization does not meet certain title insurance policy requirements within the specified time period under the agreements, excess cash flow will also be deposited into the Cash Trap Reserve Account.

(3) An amortization period commences if the DSCR is equal to or below 1.15x (the “Minimum DSCR”) at the end of any calendar quarter and continues to exist until the DSCR exceeds the Minimum DSCR for two consecutive calendar quarters.

(4) No amortization period is triggered if the outstanding principal amount of a series has not been repaid in full on the applicable anticipated repayment date. However, in that event, additional interest will accrue on the unpaid principal balance of the applicable series, and that series will begin to amortize on a monthly basis from excess cash flow.

(5) An amortization period exists if the outstanding principal amount has not been paid in full on the applicable anticipated repayment date and continues to exist until the principal has been repaid in full.

A failure to meet the noted DSCR tests could prevent GTP Acquisition Partners or the AMT Asset Subs from distributing excess cash flow to us, which could affect our ability to fund our capital expenditures, including tower construction and acquisitions and to meet REIT distribution requirements. During an “amortization period,” all excess cash flow and any amounts then in the applicable Cash Trap Reserve Account would be applied to pay the principal of the Series 2015-2 Notes or the Loan, as applicable, on each monthly payment date, and so would not be available for distribution to us. Further, additional interest will begin to accrue with respect to the Series 2015-2 Notes or subclass of the Loan from and after the anticipated repayment date at a per annum rate determined in accordance with the applicable agreement. With respect to the Series 2015-2 Notes, upon the occurrence of, and during, an event of default, the applicable trustee may, in its discretion or at the direction of holders of more than 50% of the aggregate outstanding principal of the Series 2015-2 Notes, declare the Series 2015-2 Notes immediately due and payable, in which case any excess cash flow would need to be used to pay holders of those notes. Furthermore, if GTP Acquisition Partners or the AMT Asset Subs were to default on the Series 2015-2 Notes or the Loan, the applicable trustee may seek to foreclose upon or otherwise convert the ownership of all or any portion of the 3,343 communications sites that secure the Series 2015-2 Notes or the 5,034 broadcast and wireless communications towers and related assets that secure the Loan, respectively, in which case we could lose those sites and their associated revenue.

As discussed above, we use our available liquidity and seek new sources of liquidity to fund capital expenditures, future growth and expansion initiatives, satisfy our distribution requirements and repay or repurchase our debt. If we determine that it is desirable or necessary to raise additional capital, we may be unable to do so, or such additional financing may be prohibitively expensive or restricted by the terms of our outstanding indebtedness. Further, as further discussed under Item 1A of this Annual Report under the caption “Risk Factors,” market volatility and disruption caused by inflation, rising interest rates and supply chain disruptions may impact our ability to raise additional capital through debt financing activities or our ability to repay or refinance maturing liabilities, or impact the terms of any new obligations. If we are unable to raise capital when our needs arise, we may not be able to fund capital expenditures, future growth and expansion initiatives, satisfy our REIT distribution requirements and debt service obligations, or refinance our existing indebtedness.

In addition, our liquidity depends on our ability to generate cash flow from operating activities. As set forth under Item 1A of this Annual Report under the caption “Risk Factors,” we derive a substantial portion of our revenues from a small number of customers and, consequently, a failure by a significant customer to perform its contractual obligations to us could adversely affect our cash flow and liquidity.