Accounting Policies

3 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

Accounting Policies

Accounting Policies

The interim consolidated financial statements include the accounts of ATI Inc. and its subsidiaries. Unless the context requires otherwise, “ATI” and “the Company” refer to ATI Inc. and its subsidiaries.

The Company follows a 4-4-5 or 5-4-4 fiscal calendar, whereby each fiscal quarter consists of thirteen weeks grouped into two four-week months and one five-week month, and its fiscal year ends on the Sunday closest to December 31. Unless otherwise stated, references to years and quarters in this Quarterly Report on Form 10-Q relate to fiscal years and quarters, rather than calendar years and quarters.

These unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles for interim financial information and with the instructions for Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and note disclosures required by U.S. generally accepted accounting principles for complete financial statements. In management’s opinion, all adjustments (which include only normal recurring adjustments) considered necessary for a fair presentation have been included. Certain prior year amounts have been reclassified in order to conform with year 2024 presentation. These unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s 2023 Annual Report on Form 10-K. The results of operations for these interim periods are not necessarily indicative of the operating results for any future period. The December 31, 2023 financial information has been derived from the Company’s audited consolidated financial statements.

New Accounting Pronouncements Adopted

In September 2022, the Financial Accounting Standards Board (FASB) issued new accounting guidance related to disclosures about supplier finance programs. Supplier finance programs allow a buyer to offer its suppliers the option for access to payment in advance of an invoice due date, which is paid by a third-party finance provider or intermediary on the basis of invoices that the buyer has confirmed as valid. This new guidance requires a buyer in a supplier finance program to disclose sufficient information about the program to allow a user of financial statements to understand the program’s nature, activity during the period, changes from period to period, and potential magnitude, using both qualitative and quantitative information about its supplier finance programs. This new guidance, with the exception of annual disclosures on rollforward information, was effective for the Company in fiscal year 2023, and the Company adopted this new accounting guidance effective January 2, 2023. The annual rollforward information disclosures are effective for the Company in fiscal year 2024, with early adoption permitted. The Company did not early adopt this guidance. The adoption of these changes did not have an impact on the Company’s consolidated financial statements other than disclosure requirements, which are included in Note 6.

Pending Accounting Pronouncements

In November 2023, the FASB issued new accounting guidance related to segment reporting disclosures. This guidance requires additional disclosures on an annual and interim basis of segment information, including significant segment expenses that are regularly provided to the chief operating decision maker (CODM) and the presentation and composition of other segment items, which is the difference between segment revenue less segment expenses and the measure of segment profit or loss. The guidance also requires that all current segment disclosures required on an annual basis be provided on an interim basis and requires disclosure of the title and position of the CODM and how the CODM uses the reported measure of segment profit or loss in assessing performance and allocating resources. This guidance does not change how an entity identifies its reportable segments. This new guidance includes annual disclosure requirements that will be effective for the Company for fiscal year 2024 and quarterly disclosure requirements that will be effective for fiscal year 2025. The guidance must be applied retrospectively and early adoption is permitted. The Company does not expect to early adopt this guidance and does not expect these changes to have an impact on the Company’s consolidated financial statements other than disclosure requirements.

In December 2023, the FASB issued new accounting guidance related to income tax disclosures. This guidance requires entities to disclose specific categories in its annual rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. This guidance also requires additional annual disclosures for income taxes paid and requires disaggregation of income before tax, between domestic and foreign, and income tax expense, between federal, state and foreign. This guidance also eliminates several current disclosure requirements related to: (1) the nature and estimate of the range of the reasonably possible change in the unrecognized tax benefits balance in the next 12 months, (2) making a statement that an estimate of the range cannot be made, and (3) disclosing the cumulative amount of each type of temporary difference when a deferred tax liability is not recognized because of the exceptions to comprehensive recognition of deferred taxes related to

subsidiaries and corporate joint ventures. This new guidance will be effective for the Company for fiscal year 2025 and must be applied on a prospective basis with retrospective application permitted. Early adoption of this guidance is also permitted. The Company does not expect to early adopt this guidance and does not expect these changes to have an impact on the Company’s consolidated financial statements other than disclosure requirements.