Petras Michael B. Jr. 4

4 · Sotera Health Co · Filed Mar 4, 2026

Insider Transaction Report

Form 4

Period: 2026-03-02

Sotera Health CoSHC

Petras Michael B. Jr.

DirectorChairman & CEO

Transactions

Tax Payment
Common Stock, $0.01 par value per share ("Common Stock")
[F1]
2026-03-02$15.91/sh−31,339$498,603→ 521,451 total
Tax Payment
Common Stock
[F2]
2026-03-02$15.91/sh−40,302$641,205→ 481,149 total
Exercise/Conversion
Common Stock
[F3]
2026-03-02+89,686→ 570,835 total
Tax Payment
Common Stock
[F4]
2026-03-02$15.91/sh−39,552$629,272→ 531,283 total
Tax Payment
Common Stock
[F5]
2026-03-02$15.91/sh−79,104$1,258,545→ 452,179 total
Award
Common Stock
[F6]
2026-03-02+240,248→ 692,427 total
Exercise/Conversion
Share Appreciation Units
[F3]
2026-03-02−89,686→ 59,790 total
→ Common Stock (89,686 underlying)
Award
Share Appreciation Units
[F7]
2026-03-02+120,124→ 120,124 total
→ Common Stock (120,124 underlying)

Holdings

Common Stock
(indirect: By Trust)
4,819,393

Footnotes (7)

[F1]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
[F2]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.
[F3]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.
[F4]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.
[F5]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.
[F6]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.
[F7]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.

Signature

Gregory S. Harvey, Attorney-in-Fact|2026-03-04

Documents

1 file

4
ownership.xmlPrimary
4