Statement of Changes in Beneficial Ownership (Form 4)

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person * Petras Michael B. Jr. 2. Issuer Name and Ticker or Trading Symbol Sotera Health Co [SHC] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chairman & CEO (Last) (First) (Middle) C/O SOTERA HEALTH COMPANY, 9100 SOUTH HILLS BLVD, SUITE 300 3. Date of Earliest Transaction (Month/Day/Year) 03/02/2026 (Street) BROADVIEW HEIGHTS, OH 44147 4. If Amendment, Date Original Filed (Month/Day/Year) 6. Individual or Joint/Group Filing (Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock, $0.01 par value per share ("Common Stock") 03/02/2026 F 31,339(1) D $15.91 521,451 D Common Stock 03/02/2026 F 40,302(2) D $15.91 481,149 D Common Stock 03/02/2026 M 89,686(3) A (3) 570,835 D Common Stock 03/02/2026 F 39,552(4) D $15.91 531,283 D Common Stock 03/02/2026 F 79,104(5) D $15.91 452,179 D Common Stock 03/02/2026 A 240,248(6) A $ 0 692,427 D Common Stock 4,819,393 I By Grantor Trust

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Share Appreciation Units

(3)

03/02/2026

M

89,686

(3)

(3)

Common Stock

89,686

(3)

59,790

D

Share Appreciation Units

(7)

03/02/2026

A

120,124

(7)

(7)

Common Stock

120,124

$ 0

120,124

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Petras Michael B. Jr. C/O SOTERA HEALTH COMPANY 9100 SOUTH HILLS BLVD, SUITE 300 BROADVIEW HEIGHTS, OH 44147	X		Chairman & CEO

Signatures

Gregory S. Harvey, Attorney-in-Fact		03/04/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	These securities represent the number of shares of Common Stock withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations due upon the vesting of 71,063 Restricted Stock Units ("RSUs") granted to the Reporting Person on March 6, 2023. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions
(2)	These securities represent the number of shares of Common Stock withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations due upon the vesting of 91,386 RSUs granted to the Reporting Person on March 4, 2024. This award was granted pursuant to the terms of an RSU agreement under the 2020 Incentive Plan. Each RSU represents the Reporting Person's right to recieve one share of Common Stock, subject to vesting conditions.
(3)	These securities consist of performance-based share appreciation units ("SAUs") (formerly called performance stock units) that were granted on March 3, 2025, pursuant to the terms of a SAU Agreement under the 2020 Incentive Plan. Each SAU represented the Reporting Person's right to receive one share of Common Stock subject to stock price-related performance conditions. Regarding the SAUs, the Reporting Person vested in 89,686 shares of Common Stock on March 2, 2026. The remaining SAUs under the award vest annually in equal installments in March 2027 and March 2028, subject to performance.
(4)	These securities represent the number of shares of Common Stock withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations due upon the vesting of 89,686 SAUs granted to the Reporting Person on March 3, 2025. This award was granted pursuant to the terms of a SAU Agreement under the 2020 Incentive Plan. Each SAU represents the Reporting Person's right to recieve one share of Common Stock, subject to performance.
(5)	These securities represent the number of shares of Common Stock withheld by the Issuer to satisfy the Reporting Person's tax withholding obligations due upon the vesting of 179,372 RSUs granted to the Reporting Person on March 3, 2025. This award was granted pursuant to the terms of an RSU agreement under the 2020 Incentive Plan. Each RSU represents the Reporting Person's right to recieve one share of Common Stock, subject to vesting conditions.
(6)	These securities consist of RSUs that were granted on March 2, 2026, pursuant to the terms of an RSU agreement under the 2020 Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs generally vest annually in 60%, 20%, and 20% installments, respectively, commencing March 2027.
(7)	These securities consist of a maximum number of SAUs that were granted on March 2, 2026, pursuant to the terms of a SAU Agreement under the 2020 Incentive Plan. Each SAU represents the Reporting Person's right to receive one share of Common Stock, subject to stock price-related peformance conditions. The SAUs generally vest annually in 60%, 20% and 20% installments, respectively, commencing March 2027, subject to performance.
Remarks: The Power of Attorney for Mr. Petras is filed as an exhibit to the Form 4 filed on September 12, 2024, which is incorporated by reference.

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