James Robert Foster - 01 Jan 2026 Form 3 Insider Report for ATI INC (ATI)

Role: SVP, Finance and CFO
Signature: /s/ Amanda J. Skov, Attorney-in-Fact for James Robert Foster
Issuer symbol: ATI
Transactions as of: 01 Jan 2026
Net transactions value: $0
Form type: 3
Filing time: 23 Jan 2026, 17:22:42 UTC
Next filing: 23 Jan 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Foster James Robert	SVP, Finance and CFO	C/O ATI INC., 2021 MCKINNEY AVENUE, DALLAS	/s/ Amanda J. Skov, Attorney-in-Fact for James Robert Foster	23 Jan 2026	0002106397

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
holding	ATI	Common Stock, par value $0.10 per share						29,622	01 Jan 2026	Direct	F1

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
holding	ATI	Performance Stock Units							01 Jan 2026	Common Stock, par value $0.10 per share	30,769	$0.000000	Direct	F2
holding	ATI	Performance Stock Units							01 Jan 2026	Common Stock, par value $0.10 per share	17,094	$0.000000	Direct	F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Inclusive of 2,865, 2,587 and 4,194 restricted stock units awarded in 2023, 2024 and 2025, respectively, that in each case vest in three annual installments and are settled in shares of the Issuer's Common Stock upon vesting.
F2	Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieved a specified target market price (based on a 20-trading day average) on the New York Stock Exchange for at least 20 consecutive trading dates (the "20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieved 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and 2027.
F3	Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 10-trading day average) on the NYSE for at least 20 consecutive trading days (the "Average Market Price") prior to December 31, 2029. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock acheives Average Market Prices at specified levels in excess of the target market price prior to December 31, 2029. Vested shares, if any, generally are apyable in two equal installments in early 2030 and 2031.