SHC

SEC source: 0000950170-24-066004 · ownership.xml · nonDerivative · entry 1

MIHAS CONSTANTINE S · CIK 0001262930 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,649

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 41,560 shares of Common Stock.

SEC source: 0000950170-24-066013 · ownership.xml · nonDerivative · entry 1

PETRELLA VINCENT K · CIK 0001276410 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,649

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 41,560 shares of Common Stock.

SEC source: 0000950170-24-065991 · ownership.xml · nonDerivative · entry 1

Donnini David · CIK 0001309092 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,649

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 41,560 shares of Common Stock.

SEC source: 0000950170-24-066007 · ownership.xml · nonDerivative · entry 1

Neary James · CIK 0001323057 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,649

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 41,560 shares of Common Stock.

SEC source: 0000950170-24-066037 · ownership.xml · nonDerivative · entry 1

Flynn Karen · CIK 0001553599 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,089

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

SEC source: 0000950170-24-065968 · ownership.xml · nonDerivative · entry 1

Chen Ruoxi · CIK 0001769832 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,649

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 41,560 shares of Common Stock.

SEC source: 0000950170-24-066020 · ownership.xml · nonDerivative · entry 1

Wheadon David E. · CIK 0001789507 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 55,780

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 35,691 shares of Common Stock.

SEC source: 0000950170-24-065998 · ownership.xml · nonDerivative · entry 1

Klee Ann R. · CIK 0001796076 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 106,824

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: Consist of 20,089 RSUs and 86,735 shares of Common Stock, including 79,752 shares of vested Common Stock and 6,983 shares of unvested Common Stock. The unvested shares of Common Stock will vest on a daily basis pro rata through May 27, 2025.

SEC source: 0000950170-24-066027 · ownership.xml · nonDerivative · entry 1

Knauss Robert Brown · CIK 0001951938 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,801

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 15,712 shares of Common Stock.

SEC source: 0000950170-24-065973 · ownership.xml · nonDerivative · entry 1

CUNNINGHAM SEAN LAURENCE · CIK 0001829753 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,649

F1 · shares: These securities consist of 20,089 Restricted Stock Units ("RSUs") that were granted on May 24, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 20,089 RSUs and 41,560 shares of Common Stock.

SEC source: 0000950170-24-026450 · ownership.xml · derivative · entry 5

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 68,063

Underlying: Common Stock · 68,063 shares

Expires 2034-03-04

F7 · derivative.exercise_date: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

SEC source: 0000950170-24-026450 · ownership.xml · nonDerivative · entry 4

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 544,409

F4 · shares: On March 4, 2024, the Reporting Person sold a total of 83,109 shares of Common Stock of the Issuer in an underwritten public secondary offering (the "Offering").

F5 · price: Reflects a price equal to the Offering price per share less underwriting discounts and commissions payable thereon, as disclosed in the Issuer's Prospectus 424(b)(7), filed with the United States Securities and Exchange Commission on February 29, 2024.

F6 · balance_after: These securities consist of 68,063 RSUs and 476,346 shares of Common Stock. 339,030 of the shares of Common Stock are vested, and 137,316 shares of Common Stock remain subject to vesting conditions. Shares of unvested Common Stock will vest on a daily basis, pro rata through May 13, 2025 (the five year anniversary of the date of grant).

SEC source: 0000950170-24-026450 · ownership.xml · nonDerivative · entry 3

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 627,518

F3 · shares: These securities consist of RSUs that were granted on March 4, 2024, 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 vest annually in three equal installments commencing March 2, 2025.

SEC source: 0000950170-24-026347 · ownership.xml · derivative · entry 5

Petras Michael B. Jr. · CIK 0001832387 · Chairman & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 544,509

Underlying: Common Stock · 544,509 shares

Expires 2034-03-04

F7 · derivative.exercise_date: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

F7 · balance_after: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

SEC source: 0000950170-24-026347 · ownership.xml · nonDerivative · entry 4

Petras Michael B. Jr. · CIK 0001832387 · Chairman & CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By Grantor Trust

Disclosed balance after: 5,453,580

F5 · shares: On March 4, 2024, the Reporting Person sold a total of 1,003,870 shares of Common Stock of the Issuer in an underwritten public secondary offering (the "Offering").

F6 · price: Reflects a price equal to the Offering price per share less underwriting discounts and commissions payable thereon, as disclosed in the Issuer's Prospectus 424(b)(7), filed with the United States Securities and Exchange Commission on February 29, 2024.

SEC source: 0000950170-24-026347 · ownership.xml · nonDerivative · entry 3

Petras Michael B. Jr. · CIK 0001832387 · Chairman & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 699,749

F3 · shares: These securities consist of RSUs that were granted on March 4, 2024, 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 vest annually in three equal installments commencing March 2, 2025.

F4 · balance_after: These securities consist of 543,910 RSUs and 155,839 shares of Common Stock.

SEC source: 0001999371-24-003175 · sotera-form4.xml · nonDerivative · entry 1

WARBURG PINCUS & CO. · CIK 0000929408 · Director · 10% owner

Warburg Pincus Private Equity XI, L.P. · CIK 0001540163 · Director · 10% owner

WP XI Partners, L.P. · CIK 0001540164 · Director · 10% owner

Warburg Pincus XI Partners, L.P. · CIK 0001540386 · Director · 10% owner

Warburg Pincus Private Equity XI-B, L.P. · CIK 0001540166 · Director · 10% owner

Bull Co-Invest L.P. · CIK 0001832693 · Director · 10% owner

Bull Holdco L.P. · CIK 0002014247 · Director · 10% owner

Warburg Pincus XI, L.P. · CIK 0001540167 · Director · 10% owner

WP Global LLC · CIK 0001540385 · Director · 10% owner

Warburg Pincus Partners II, L.P. · CIK 0001658787 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 88,822,952

F1 · shares: On March 4, 2024, certain of the Warburg Pincus Entities (as defined below) sold a total of 16,594,363 shares of Common Stock of Sotera Health Company (the "Issuer") in an underwritten public secondary offering (the "Offering").

F2 · balance_after: Following the Offering, consists of (i) 71,083,263 shares of Common Stock of the Issuer held by Bull Holdco L.P. ("Bull Holdco") and (iii) 17,739,689 shares of Common Stock of the Issuer held by Bull Co-Invest L.P., a Delaware limited partnership ("Bull Co-Invest").

F3 · ownership.nature: Warburg Pincus XI, L.P., a Delaware limited partnership ("WP XI GP"), is the general partner of each of (i) Warburg Pincus Private Equity XI, L.P. ("WP XI"), (ii) Warburg Pincus Private Equity XI-B, L.P. ("WP XI-B"), (iii) WP XI Partners, L.P. ("WP XI Partners") and (iv) Warburg Pincus XI Partners, L.P. ("Warburg Pincus XI Partners"). WP Global LLC ("WP Global"), is the general partner of WP XI GP. Warburg Pincus Partners II, L.P. ("WPP II"), is the managing member of WP Global. Warburg Pincus Partners GP LLC ("WPP GP LLC"), is the general partner of WPP II. Warburg Pincus & Co. ("WP"), is the managing member of WPP GP LLC. Warburg Pincus (Cayman) XI, L.P. ("WP XI Cayman GP"), is the general partner of Warburg Pincus Private Equity XI-C, L.P. ("WP XI-C" and, together with WP XI, WP XI-B, WP XI Partners and Warburg Pincus XI Partners, the "WP XI Funds").

F4 · ownership.nature: The WP XI Funds, Bull Co-Invest, Bull Holdco, WP Global, WPP II, WPP GP LLC, WP XI Cayman GP, WP XI-C LLC, WPP II Cayman, WP Bermuda GP, WP Bull Manager, WP LLC and WP are collectively referred to herein as the "Warburg Pincus Entities."

F5 · ownership.nature: Each Warburg Pincus Entity disclaims beneficial ownership with respect to any shares of Common Stock of the Issuer, except to the extent of its pecuniary interest in such shares of Common Stock, if any. The WP XI Funds, Bull Co-Invest, Bull Holdco, WP Global, WPP II, WPP GP LLC, WP XI Cayman GP, WP XI-C LLC, WPP II Cayman, WP Bermuda GP, WP Bull Manager, WP LLC and WP are directors-by-deputization solely for purposes of Section 16 of the Securities Exchange Act of 1934, as amended. Information with respect to each of the Warburg Pincus Entities is given solely by such Warburg Pincus Entity, and no Warburg Pincus Entity has responsibility for the accuracy or completeness of information supplied by another Warburg Pincus Entity.

F6 · ownership.nature: Warburg Pincus XI-C, LLC ("WP XI-C LLC"), is the general partner of WP XI Cayman GP. Warburg Pincus Partners II (Cayman), L.P. ("WPP II Cayman"), is the managing member of WP XI-C LLC. Warburg Pincus (Bermuda) Private Equity GP Ltd. ("WP Bermuda GP"), is the general partner of WPP II Cayman. WP Bull Manager LLC ("WP Bull Manager"), is the general partner of Bull Co-Invest. WP is managing member of WP Bull Manager. Warburg Pincus LLC, a New York limited liability company ("WP LLC"), is the manager of the WP XI Funds. The WP XI Funds share limited partnership ownership in Bull Holdco on a pro rata basis in accordance with their respective numbers of Contributed Shares.

SEC source: 0001999371-24-003176 · sotera_form4-030624.xml · nonDerivative · entry 1

WARBURG PINCUS & CO. · CIK 0000929408 · Director · 10% owner

Warburg Pincus Private Equity XI-C, L.P. · CIK 0001550877 · Director · 10% owner

Warburg Pincus (Cayman) XI, L.P. · CIK 0001554853 · Director · 10% owner

Warburg Pincus XI-C, LLC · CIK 0001554852 · Director · 10% owner

Warburg Pincus Partners II (Cayman), L.P. · CIK 0001658820 · Director · 10% owner

Warburg Pincus (Bermuda) Private Equity GP Ltd. · CIK 0001555729 · Director · 10% owner

WARBURG PINCUS LLC · CIK 0001162870 · Director · 10% owner

Warburg Pincus Partners GP LLC · CIK 0001621224 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 88,822,952

F1 · shares: On March 4, 2024, certain of the Warburg Pincus Entities (as defined below) sold a total of 16,594,363 shares of Common Stock of Sotera Health Company (the "Issuer") in an underwritten public secondary offering (the "Offering").

F2 · balance_after: Following the Offering, consists of (i) 71,083,263 shares of Common Stock of the Issuer held by Bull Holdco L.P. ("Bull Holdco") and (iii) 17,739,689 shares of Common Stock of the Issuer held by Bull Co-Invest L.P., a Delaware limited partnership ("Bull Co-Invest").

F3 · ownership.nature: Warburg Pincus XI, L.P., a Delaware limited partnership ("WP XI GP"), is the general partner of each of (i) Warburg Pincus Private Equity XI, L.P. ("WP XI"), (ii)Warburg Pincus Private Equity XI-B, L.P. ("WP XI-B"), (iii) WP XI Partners, L.P. ("WP XI Partners") and (iv) Warburg Pincus XI Partners, L.P. ("Warburg Pincus XI Partners"). WP Global LLC ("WP Global"), is the general partner of WP XI GP. Warburg Pincus Partners II, L.P. ("WPP II"), is the managing member of WP Global.Warburg Pincus Partners GP LLC ("WPP GP LLC"), is the general partner of WPP II. Warburg Pincus & Co. ("WP"), is the managing member of WPP GP LLC.Warburg Pincus (Cayman) XI, L.P. ("WP XI Cayman GP"), is the general partner of Warburg Pincus Private Equity XI-C, L.P. ("WP XI-C" and, together with WP XI,WP XI-B, WP XI Partners and Warburg Pincus XI Partners, the "WP XI Funds").

F4 · ownership.nature: The WP XI Funds, Bull Co-Invest, Bull Holdco, WP Global, WPP II, WPP GP LLC, WP XI Cayman GP, WP XI-C LLC, WPP II Cayman, WP Bermuda GP, WP Bull Manager, WP LLC and WP are collectively referred to herein as the "Warburg Pincus Entities."

F5 · ownership.nature: Each Warburg Pincus Entity disclaims beneficial ownership with respect to any shares of Common Stock of the Issuer, except to the extent of its pecuniary interest in such shares of Common Stock, if any. The WP XI Funds, Bull Co-Invest, Bull Holdco, WP Global, WPP II, WPP GP LLC, WP XI Cayman GP, WP XI-C LLC, WPP II Cayman, WP Bermuda GP, WP Bull Manager, WP LLC and WP are directors-by-deputization solely for purposes of Section 16 of the Securities Exchange Act of 1934, as amended. Information with respect to each of the Warburg Pincus Entities is given solely by such Warburg Pincus Entity, and no Warburg Pincus Entity has responsibility for the accuracy or completeness of information supplied by another Warburg Pincus Entity.

F6 · ownership.nature: Warburg Pincus XI-C, LLC ("WP XI-C LLC"), is the general partner of WP XI Cayman GP. Warburg Pincus Partners II (Cayman), L.P. ("WPP II Cayman"), is the managing member of WP XI-C LLC. Warburg Pincus (Bermuda) Private Equity GP Ltd. ("WP Bermuda GP"), is the general partner of WPP II Cayman. WP Bull Manager LLC ("WP Bull Manager"), is the general partner of Bull Co-Invest. WP is managing member of WP Bull Manager. Warburg Pincus LLC, a New York limited liability company ("WP LLC"), is the manager of the WP XI Funds. The WP XI Funds share limited partnership ownership in Bull Holdco on a pro rata basis in accordance with their respective numbers of Contributed Shares.

SEC source: 0000950170-24-027276 · ownership.xml · derivative · entry 2

Lyons Jonathan M. · CIK 0001983511 · Sr. Vice President, CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 81,676

Underlying: Common Stock · 81,676 shares

Expires 2034-03-04

F3 · derivative.exercise_date: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

F3 · balance_after: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

SEC source: 0000950170-24-027276 · ownership.xml · nonDerivative · entry 1

Lyons Jonathan M. · CIK 0001983511 · Sr. Vice President, CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 118,091

F1 · shares: These securities consist of Restricted Stock Units ("RSUs") that were granted on March 4, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs vest annually in three equal installments commencing March 2, 2025.

F2 · balance_after: These securites consist of 118,091 RSUs.

SEC source: 0000950170-24-027246 · ownership.xml · derivative · entry 2

DIMITRIEF ALEXANDER · CIK 0001614732 · SVP, General Counsel and Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 102,095

Underlying: Common Stock · 102,095 shares

Expires 2034-03-04

F3 · derivative.exercise_date: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

F3 · balance_after: These options were granted on March 4, 2024, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2025, subject to vesting conditions.

SEC source: 0000950170-24-027246 · ownership.xml · nonDerivative · entry 1

DIMITRIEF ALEXANDER · CIK 0001614732 · SVP, General Counsel and Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 286,883

F1 · shares: These securities consist of Restricted Stock Units ("RSUs") that were granted on March 4, 2024, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs vest annually in three equal installments commencing March 2, 2025.

F2 · balance_after: These securities consist of 51,405 RSUs, 117,739 shares of Common Stock that have vested and 117,739 shares of Common Stock that will vest on October 31, 2024, subject to the Reporting Person's continued service through such date.

SEC source: 0001999371-24-003174 · sotera-form4_030424.xml · nonDerivative · entry 1

GTCR INVESTMENT XI LLC · CIK 0001827977 · Director · 10% owner

GTCR FUND XI/A LP · CIK 0001591434 · Director · 10% owner

GTCR FUND XI/C LP · CIK 0001591436 · Director · 10% owner

GTCR CO-INVEST XI LP · CIK 0001591432 · Director · 10% owner

GTCR PARTNERS XI/A&C LP · CIK 0001828028 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 59,215,301

F1 · shares: On March 4, 2024, the GTCR XI Funds (as defined below) sold a total of 11,062,908 shares of Common Stock of Sotera Health Company (the "Issuer") in an underwritten public secondary offering (the "Offering").

F2 · balance_after: Following the Offering, consists of (i) 46,997,881 shares of Common Stock held directly by GTCR Fund XI/A LP, a Delaware limited partnership ("Fund XI/A"), (ii) 11,840,751 shares of Common Stock held directly by GTCR Fund XI/C LP, a Delaware limited partnership ("Fund XI/C"), and (iii) 376,669 shares of Common Stock held directly by GTCR Co-Invest XI LP, a Delaware limited partnership ("Co-Invest XI", and together with Fund XI/A and Fund XI/C, the "GTCR XI Funds").

F3 · ownership.nature: GTCR Partners XI/A&C LP ("Partners XI/A&C") is the general partner of each of Fund XI/A and Fund XI/C. GTCR Investment XI LLC ("Investment XI" and together with the GTCR XI Funds and Partners XI/A&C, the "GTCR Entities"), is the general partner of Co-Invest XI and Partners XI/A&C. Investment XI is managed by a board of managers (the "GTCR Board of Managers") consisting of Mark M. Anderson, Aaron D. Cohen, Sean L. Cunningham, Benjamin J. Daverman, David A Donnini, Constantine S. Mihas and Collin E. Roche, and no single person has voting or dispositive authority over the shares of Common Stock.

F4 · ownership.nature: Each of GTCR Partners XI/A&C, GTCR Investment XI and the GTCR Board of Managers may be deemed to share beneficial ownership of the shares of Common Stock held of record by the GTCR XI Funds, and each of the individual members of the GTCR Board of Managers disclaims beneficial ownership of the shares of Common Stock held of record by the GTCR XI Funds except to the extent of his pecuniary interest therein.

F5 · ownership.nature: Each of the reporting persons is a director-by-deputization solely for purposes of Section 16 of the Exchange Act. Information with respect to each of the GTCR Entities is given solely by such GTCR Entity, and no GTCR Entity has responsibility for the accuracy or completeness of information supplied by another GTCR Entity.

SEC source: 0000950170-24-027236 · ownership.xml · nonDerivative · entry 1

Klee Ann R. · CIK 0001796076 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 86,735

F1 · shares: On March 4, 2024, the Reporting Person sold a total of 5,750 shares of Common Stock of the Issuer in an underwritten public secondary offering (the "Offering").

F2 · price: Reflects a price equal to the Offering price per share less underwriting discounts and commissions payable thereon, as disclosed in the Issuer's Prospectus 424(b)(7), filed with the United States Securities and Exchange Commission on February 29, 2024.

F3 · balance_after: Consists of 15,712 Restricted Stock Units and 71,023 shares of Common Stock, including 62,537 shares of vested Common Stock and 8,486 shares of unvested Common Stock. The unvested shares of Common Stock will vest on a daily basis pro rata through May 27, 2025.

SEC source: 0000950170-24-026450 · ownership.xml · nonDerivative · entry 2

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 593,248

F2 · shares: 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 9,475 RSUs, which represents 33% of the RSU award granted to the Reporting Person on March 6, 2023. 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 receive one share of Common Stock, subject to vesting conditions.

SEC source: 0000950170-24-026450 · ownership.xml · nonDerivative · entry 1

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 596,311

F1 · shares: 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 8,320 Restricted Stock Units ("RSUs"), which represents 33% of the RSU award granted to the Reporting Person on March 2, 2022. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions.

SEC source: 0000950170-24-026347 · ownership.xml · nonDerivative · entry 2

Petras Michael B. Jr. · CIK 0001832387 · Chairman & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 425,589

F2 · shares: 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 RSUs, which represents 33% of the RSU award granted to the Reporting Person on March 6, 2023. 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 receive one share of Common Stock, subject to vesting conditions.

SEC source: 0000950170-24-026347 · ownership.xml · nonDerivative · entry 1

Petras Michael B. Jr. · CIK 0001832387 · Chairman & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 447,163

F1 · shares: 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 62,406 Restricted Stock Units ("RSUs"), which represents 33% of the RSU award granted to the Reporting Person on March 2, 2022. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions.

SEC source: 0001822479-23-000071 · wk-form4_1700687335.xml · nonDerivative · entry 1

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 598,749

F1 · shares: 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 6,522 Restricted Stock Units ("RSUs"), which represents 25% of the RSU award granted to the Reporting Person on November 20, 2020. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus 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 · price: Represents the closing price of the Company's Common Stock on November 20, 2023.

F3 · balance_after: These securities consist of 51,588 RSUs and 547,161 shares of Common Stock. 376,230 of the shares of Common Stock are vested, and 170,931 shares of Common Stock remain subject to vesting conditions. Shares of unvested Common Stock will vest on a daily basis, pro rata through May 13, 2025 (the five year anniversary of the date of grant).

SEC source: 0001822479-23-000070 · wk-form4_1700687309.xml · nonDerivative · entry 1

Petras Michael B. Jr. · CIK 0001832387 · Director · Chairman & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 555,418

F1 · shares: 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 65,217 Restricted Stock Units ("RSUs"), which represents 25% of the RSU award granted to the Reporting Person on November 20, 2020. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus 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 · price: Represents the closing price of the Company's Common Stock on November 20, 2023.

F3 · balance_after: These securities consist of 403,219 RSUs and 152,199 shares of Common Stock.

SEC source: 0001209191-23-045237 · doc4.xml · derivative · entry 2

Lyons Jonathan M. · CIK 0001983511 · Sr. Vice President, CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 33,640

Underlying: Common Stock · 33,640 shares

Expires 2033-08-07

F2 · derivative.exercise_date: These options were granted on August 7, 2023, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing August 5, 2024, subject to the Reporting Person's continued service through each such date.

SEC source: 0001209191-23-045237 · doc4.xml · nonDerivative · entry 1

Lyons Jonathan M. · CIK 0001983511 · Sr. Vice President, CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 76,967

F1 · shares: These securities consist of Restricted Stock Units ("RSUs") that were granted on August 7, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs vest annually in three equal installments commencing on August 5, 2024, subject to the Reporting Person's continued service through each such date.

SEC source: 0001209191-23-033147 · doc4.xml · nonDerivative · entry 1

MIHAS CONSTANTINE S · CIK 0001262930 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,560

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 25,848 shares of Common Stock.

SEC source: 0001209191-23-033151 · doc4.xml · nonDerivative · entry 1

PETRELLA VINCENT K · CIK 0001276410 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,560

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 25,848 shares of Common Stock.

SEC source: 0001209191-23-033129 · doc4.xml · nonDerivative · entry 1

Donnini David · CIK 0001309092 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,560

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 25,848 shares of Common Stock.

SEC source: 0001209191-23-033149 · doc4.xml · nonDerivative · entry 1

Neary James · CIK 0001323057 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,560

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 25,848 shares of Common Stock.

SEC source: 0001209191-23-033124 · doc4.xml · nonDerivative · entry 1

Chen Ruoxi · CIK 0001769832 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,560

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 25,848 shares of Common Stock.

SEC source: 0001209191-23-033161 · doc4.xml · nonDerivative · entry 1

Wheadon David E. · CIK 0001789507 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,691

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 19,979 shares of Common Stock.

SEC source: 0001209191-23-033133 · doc4.xml · nonDerivative · entry 1

Klee Ann R. · CIK 0001796076 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 92,485

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: Consists of 15,712 RSUs and 76,773 shares of Common Stock, including 62,864 shares of vested Common Stock and 13,909 shares of unvested Common Stock. The unvested shares of Common Stock will vest on a daily basis pro rata through May 27, 2025.

SEC source: 0001209191-23-033140 · doc4.xml · nonDerivative · entry 1

Knauss Robert Brown · CIK 0001951938 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 15,712

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

SEC source: 0001209191-23-033126 · doc4.xml · nonDerivative · entry 1

CUNNINGHAM SEAN LAURENCE · CIK 0001829753 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,560

F1 · shares: These securities consist of 15,712 Restricted Stock Units ("RSUs") that were granted on May 26, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan. Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs will vest in full on the earlier of (i) the first anniversary of the date of grant, or (ii) the date immediately prior to the Issuer's next regular annual shareholders meeting, subject to the Reporting Person's continued service as a non-employee director of the Issuer through such date.

F2 · balance_after: These securities consist of 15,712 RSUs and 25,848 shares of Common Stock.

SEC source: 0001822479-23-000023 · wf-form4_167831510631450.xml · derivative · entry 2

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 53,879

Underlying: Common Stock · 53,879 shares

Expires 2033-03-06

F3 · derivative.exercise_date: These options were granted on March 6, 2023, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2024, subject to the Reporting Person's continued service through each such date.

SEC source: 0001822479-23-000023 · wf-form4_167831510631450.xml · nonDerivative · entry 1

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 600,660

F1 · shares: These securities consist of Restricted Stock Units ("RSUs") that were granted on March 6, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs vest annually in three equal installments commencing March 2, 2024, subject to the Reporting Person's continued service through each such date.

F2 · balance_after: These securities consist of 58,110 RSUs and 542,550 shares of Common Stock. 289,482 of the shares of Common Stock are vested, and 253,068 shares of Common Stock remain subject to vesting conditions. Shares of unvested Common Stock will vest on a daily basis, pro rata through May 13, 2025 (the five year anniversary of the date of grant).

SEC source: 0001822479-23-000021 · wf-form4_167831492828392.xml · derivative · entry 3

Petras Michael B. Jr. · CIK 0001832387 · Director · Chairman & CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 404,094

Underlying: Common Stock · 404,094 shares

Expires 2033-03-06

F4 · derivative.exercise_date: These options were granted on March 6, 2023, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2024, subject to vesting conditions.

F4 · balance_after: These options were granted on March 6, 2023, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing March 2, 2024, subject to vesting conditions.

SEC source: 0001822479-23-000021 · wf-form4_167831492828392.xml · nonDerivative · entry 1

Petras Michael B. Jr. · CIK 0001832387 · Director · Chairman & CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 584,668

F1 · shares: These securities consist of Restricted Stock Units ("RSUs") that were granted on March 6, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs vest annually in three equal installments commencing March 2, 2024.

F2 · balance_after: These securities consist of 468,436 RSUs and 116,232 shares of Common Stock.

SEC source: 0001822479-23-000019 · wf-form4_167814657784926.xml · nonDerivative · entry 1

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 572,235

F1 · shares: 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 8,320 Restricted Stock Units ("RSUs"), which represents 33% of the RSU award granted to the Reporting Person on March 2, 2022. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus 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 · price: Represents the closing price of the Company's Common Stock on March 2, 2023.

F3 · balance_after: These securities consist of 29,685 RSUs and 542,550 shares of Common Stock. 273,621 of the shares of Common Stock are vested, and 254,336 shares of Common Stock remain subject to vesting conditions. Shares of unvested Common Stock will vest on a daily basis, pro rata through May 13, 2025 (the five year anniversary of the date of grant).

SEC source: 0001822479-23-000017 · wf-form4_167814642447695.xml · nonDerivative · entry 1

Petras Michael B. Jr. · CIK 0001832387 · Director · Chairman & CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 371,479

F1 · shares: 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 62,406 Restricted Stock Units ("RSUs"), which represents 33% of the RSU award granted to the Reporting Person on March 2, 2022. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus 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 · price: Represents the closing price of the Company's Common Stock on March 2, 2023.

F3 · balance_after: These securities consist of 255,247 RSUs and 116,232 shares of Common Stock.

SEC source: 0001822479-22-000082 · wf-form4_166915455192982.xml · nonDerivative · entry 1

Rutz Michael P · CIK 0001599220 · President of Sterigenics

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 575,183

F1 · shares: 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 6,521 Restricted Stock Units ("RSUs"), which represents 25% of the RSU award granted to the Reporting Person on November 20, 2020. This RSU award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus 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 · price: Represents the closing price of the Company's Common Stock on November 18, 2022.

F3 · balance_after: These securities consist of 38,005 RSUs and 537,178 shares of Common Stock. 250,495 of the shares of Common Stock are vested, and 286,683 shares of Common Stock remain subject to vesting conditions. Shares of unvested Common Stock will vest on a daily basis, pro rata through May 13, 2025 (the five year anniversary of the date of grant).

SEC source: 0001822479-22-000080 · wf-form4_166915442637925.xml · nonDerivative · entry 1

Petras Michael B. Jr. · CIK 0001832387 · Director · Chairman & CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 391,320

F1 · shares: 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 65,218 Restricted Stock Units ("RSUs"), which represents 25% of the RSU award granted to the Reporting Person on November 20, 2020. This award was granted pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus 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 · price: Represents the closing price of the Company's Common Stock on November 18, 2022.

F3 · balance_after: These securities consist of 317,653 RSUs and 73,667 shares of Common Stock.

SEC source: 0001822479-22-000076 · wf-form4_166803216571483.xml · derivative · entry 2

DIMITRIEF ALEXANDER · CIK 0001614732 · SVP, General Counsel and Sec.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 602,387

Underlying: Common Stock · 602,387 shares

Expires 2032-11-07

F3 · derivative.exercise_date: These options were granted on November 7, 2022, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest in two equal installments on each of October 31, 2023 and October 31, 2024, subject to the Reporting Person's continued service through each such date.

F3 · balance_after: These options were granted on November 7, 2022, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest in two equal installments on each of October 31, 2023 and October 31, 2024, subject to the Reporting Person's continued service through each such date.