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We consent to the incorporation by reference in the Registration Statement (No. 333-188641) on Form S-8 of ATI Inc. of our report dated June 13, 2025, with respect to the statements of net assets available for benefits of ATI 401(k) Savings Plan as of December 31, 2024 and 2023, the related statement of changes in net assets available for benefits for the year ended December 31, 2024, and the related supplemental schedule as of December 31, 2024, which report appears in the December 31, 2024 annual report on Form 11-K of ATI 401(k) Savings Plan.