Michael B. Miller - 05 Dec 2025 Form 4 Insider Report for ATI INC (ATI)

Reporting relationship: VP Chief Accounting Officer
Issuer ticker: ATI
Reported as of: 05 Dec 2025
Net transaction value: $0
SEC form: 4
Accepted by SEC: 09 Dec 2025, 18:15:00 UTC
Prior SEC filing: 21 Mar 2025
Next SEC filing: 07 Jan 2026
Source filing: View source filing
Reporting owner signature: /s/ Michael B. Miller

Key filing fact

Michael B. Miller filed Form 4 for ATI INC (ATI) on 09 Dec 2025.

Key facts

This page summarizes Michael B. Miller's Form 4 filing for ATI INC (ATI).
1 reported transaction and 1 derivative row are listed below.
Accepted by SEC: 09 Dec 2025, 18:15.

Change

Previous filing in this sequence was filed on 21 Mar 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001880164 Primary reporting owner

Miller Michael Benjamin

Relationship: VP Chief Accounting Officer
Address: C/O ATI INC., 2021 MCKINNEY AVENUE, SUITE 1100, DALLAS
Signature: /s/ Michael B. Miller
Signature date: 09 Dec 2025

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

ATI transaction Derivative

Performance Stock Unit

Award

Transaction value
Shares: +1,709
Change %
Price
Shares after: 1,709
Date: 05 Dec 2025
Ownership: Direct
Underlying class: Common Stock, par value $0.10 per share
Underlying amount: 1,709
Exercise price
Footnotes: F1, F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

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.

Footnote F2

Awarded under the Issuer's 2022 Incentive Plan.