ROBERT S. WETHERBEE - 05 Jan 2026 Form 4 Insider Report for ATI INC (ATI)

Signature
/s/ Amanda J. Skov, Attorney-in-Fact for Robert S. Wetherbee
Issuer symbol
ATI
Transactions as of
05 Jan 2026
Net transactions value
-$19,166,601
Form type
4
Filing time
07 Jan 2026, 17:25:58 UTC
Previous filing
19 Dec 2025
Next filing
15 Jan 2026

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
WETHERBEE ROBERT S Executive Chairman, Director 2021 MCKINNEY AVENUE, SUITE 1100, DALLAS /s/ Amanda J. Skov, Attorney-in-Fact for Robert S. Wetherbee 07 Jan 2026 0001572385

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction ATI Common Stock, par value $0.10 per share Options Exercise $0 +362,644 $0.000000 186,538 05 Jan 2026 Direct F1
transaction ATI Common Stock, par value $0.10 per share Tax liability $8,399,199 -69,369 -19% $121.08 293,275 05 Jan 2026 Direct F2, F7
transaction ATI Common Stock, par value $0.10 per share Award $0 +185,276 +63% $0.000000 478,551 05 Jan 2026 Direct F3, F4
transaction ATI Common Stock, par value $0.10 per share Tax liability $8,827,580 -72,907 -15% $121.08 405,644 05 Jan 2026 Direct F2, F5
transaction ATI Common Stock, par value $0.10 per share Tax liability $1,939,823 -16,021 -3.9% $121.08 389,623 05 Jan 2026 Direct F2, F6

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
transaction ATI Performance Stock Unit Options Exercise $0 -64,103 -50% $0.000000 64,102 05 Jan 2026 Common Stock, par value $0.10 per share 176,106 $0.000000 Direct F1
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Settlement of one-half of certain Performance Stock Units awarded in 2022 ("2022 Breakout Performance Units"), each of which represented a contingent right to receive shares of the Issuer's Common Stock if the Issuer's Common Stock achieved specified target market prices (based on a 20-trading day average) on the New York Stock Exchange ("NYSE") for at least 20 consecutive trading days (the "20-day Average Market Price") prior to December 31, 2025, up to a maximum of three shares per Unit. The shares underlying one-half of the 2022 Breakout Performance Units became payable as of January 5, 2026 following certification of the Issuer's achievement of the relevant performance criteria by the Compensation and Leadership Development Committee of the Company's Board of Directors (the "CLDC"). The remaining half of the 2022 Breakout Performance Units are scheduled by their terms to become payable in early 2027.
F2 Represents the average of the high and low trading prices for one share of the Issuer's Common Stock on the NYSE on January 5, 2026.
F3 Settlement of performance-vested restricted stock units that were granted in 2023, the vesting of which was contingent on the Issuer's total shareholder return relative to a specified peer group during the period from January 1, 2023 through December 31, 2025 (the "2023-2025 PSUs"). The shares underlying the 2023-2025 PSUs became payable as of January 5, 2026 following certification of the Issuer's achievement of the relevant performance criteria by the CLDC.
F4 Awarded under the Issuer's 2022 Incentive Plan.
F5 Shares withheld for the payment of taxes in connection with the settlement of the 2023-2025 PSUs.
F6 Shares withheld for payment of taxes on restricted stock units awarded in 2023, 2024 and 2025.
F7 Shares withheld for the payment of taxes in connection with the settlement of 2022 Breakout Performance Units.