# EDGAR Filing Document

**Accession Number:** 0002106397
**File Stem:** 0001193125-26-021288
**Filing Date:** 2026-1
**Character Count:** 6426
**Document Hash:** 0e6ffa138e6a45e3c89a3bc1dce6fc4d
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-021288.hdr.sgml**: 20260123

**ACCESSION NUMBER**: 0001193125-26-021288

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260101

**FILED AS OF DATE**: 20260123

**DATE AS OF CHANGE**: 20260123

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Foster James Robert
- **CENTRAL INDEX KEY:** 0002106397

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-12001
- **FILM NUMBER:** 26557765

**MAIL ADDRESS:**
- **STREET 1:** C/O ATI INC.
- **STREET 2:** 2021 MCKINNEY AVENUE
- **CITY:** DALLAS
- **STATE:** TX
- **ZIP:** 75201
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ATI INC
- **CENTRAL INDEX KEY:** 0001018963
- **STANDARD INDUSTRIAL CLASSIFICATION:** STEEL PIPE & TUBES [3317]
- **ORGANIZATION NAME:** 04 Manufacturing
- **EIN:** 251792394
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1228

**BUSINESS ADDRESS:**
- **STREET 1:** 2021 MCKINNEY AVENUE
- **CITY:** DALLAS
- **STATE:** TX
- **ZIP:** 75201
- **BUSINESS PHONE:** 4123942800

**MAIL ADDRESS:**
- **STREET 1:** 2021 MCKINNEY AVENUE
- **CITY:** DALLAS
- **STATE:** TX
- **ZIP:** 75201

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** ALLEGHENY TECHNOLOGIES INC
- **DATE OF NAME CHANGE:** 19991213

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** ALLEGHENY TELEDYNE INC
- **DATE OF NAME CHANGE:** 19960716

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Foster James Robert<br><sub>(Last) (First) (Middle)</sub><br>C/O ATI INC.<br>2021 MCKINNEY AVENUE<br><sub>(Street)</sub><br>DALLAS, TX 75201<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>ATI INC [ ATI ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2026-01-01 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [ ] 10% Owner<br>[X] Officer (give title below)   [ ] Other (specify below)<br>_SVP, Finance and CFO_ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

---

|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |
| Common Stock, par value $0.10 per share | 29622<sup>(1)</sup> | D |  |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| Performance Stock Units | 2025-12-31<sup>(2)</sup> | 2025-12-31<sup>(2)</sup> | Common Stock, par value $0.10 per share | 30769 | 0.00<sup>(2)</sup> | D |  |
| Performance Stock Units | 2029-12-31<sup>(3)</sup> | 2029-12-31<sup>(3)</sup> | Common Stock, par value $0.10 per share | 17094 | 0.00<sup>(3)</sup> | D |  |

---

### Footnotes:

(1) 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.

(2) 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.

(3) 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.

**Signature:** /s/ Amanda J. Skov, Attorney-in-Fact for James Robert Foster  
**Date:** 2026-01-23

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**