GTCR Reporting Persons filed Amendment No. 6 to a Schedule 13G/A reporting shared voting power over 31,838,253 shares of Sotera Health Co. That amount represents approximately 11.2% of the 284,392,079 shares outstanding as of February 17, 2026, per the issuer's prospectus supplement.
The filing states the GTCR investors and the Warburg Pincus investors are party to a Stockholders Agreement covering governance and voting arrangements; the filing also notes that GTCR expressly disclaims beneficial ownership of shares owned of record by the Warburg Pincus investors. The filing is a joint disclosure by several GTCR entities, with signatures by Jeffrey Wright.
Positive
None.
Negative
None.
Insights
Joint filing clarifies group voting ties and disclaimers.
The Schedule 13G/A amendment records 31,838,253 shares tied to GTCR and Warburg Pincus under a Stockholders Agreement. The filing describes agreed voting arrangements for director-related matters and quantifies the combined position as 11.2% of outstanding shares as of February 17, 2026.
The filing also contains explicit legal language: each GTCR Reporting Person "expressly disclaims beneficial ownership" of shares held of record by the Warburg Pincus investors. Subsequent disclosures by the Warburg Pincus entities are the appropriate source for their precise holdings.
Disclosure signals a coordinated block but not direct dispositive control.
The filing lists shared voting power of 31,838,253 shares and specifies GTCR-owned record shares totaling 12,735,301 across GTCR entities, with the Warburg Pincus sponsors reported at 19,102,952 in a separate Form 4.
This is a static ownership disclosure for market participants; cash‑flow treatment and any planned transactions are not described. Future filings by the group members may clarify voting coordination or transfers.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 6)
Sotera Health Co.
(Name of Issuer)
Common Stock, par value $0.01 per share
(Title of Class of Securities)
03/06/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
SCHEDULE 13G
CUSIP Number(s):
1
Names of Reporting Persons
GTCR INVESTMENT XI LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
31,838,253.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
12,735,301.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
31,838,253.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
11.2 %
12
Type of Reporting Person (See Instructions)
OO
Comment for Type of Reporting Person: (1) As more fully described in Item 4 of this Amendment No. 6 to Schedule 13G, the GTCR Investors (as defined in Item 2) are party to a Stockholders Agreement with the Warburg Pincus Investors (as defined in Item 4) and certain other holders of Common Stock of the Issuer. The GTCR Investors, together with the Warburg Pincus Investors, hold an aggregate total of 31,838,253 shares of Common Stock of the Issuer (approximately 11.2% of the outstanding shares of Common Stock of the Issuer), of which 19,102,952 shares of Common Stock are publicly reported as being owned by the Warburg Pincus Investors in such entities' Form 4, filed with the U.S. Securities and Exchange Commission ("Commission") on March 10, 2026. Although the GTCR Reporting Persons (as defined in Item 2) may be deemed to beneficially own the Common Stock held of record by the Warburg Pincus Investors as a result of the Stockholders Agreement, each GTCR Reporting Person expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Securities Exchange Act of 1934, as amended (the "Exchange Act")) with respect to any shares of Common Stock other than the shares of Common Stock of the Issuer owned of record by such GTCR Reporting Person. The percentages used herein have been determined in accordance with footnote 2 below. Capitalized terms used herein are defined in Items 2(a) or 4 below.
(2) Calculated based on 284,392,079 shares of Common Stock outstanding as of February 17, 2026 as reported on the Issuer's final prospectus supplement, filed pursuant to Rule 424(b)(7) on March 5, 2026.
SCHEDULE 13G
CUSIP Number(s):
1
Names of Reporting Persons
GTCR FUND XI/A LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
31,838,253.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
10,107,727.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
31,838,253.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
11.2 %
12
Type of Reporting Person (See Instructions)
PN
Comment for Type of Reporting Person: (1) As more fully described in Item 4 of this Amendment No. 6 to Schedule 13G, the GTCR Investors are party to a Stockholders Agreement with the Warburg Pincus Investors and certain other holders of Common Stock of the Issuer. The GTCR Investors, together with the Warburg Pincus Investors, hold an aggregate total of 31,838,253 shares of Common Stock of the Issuer (approximately 11.2% of the outstanding shares of Common Stock of the Issuer), of which 19,102,952 shares of Common Stock are publicly reported as being owned by the Warburg Pincus Investors in such entities' Form 4, filed with the Commission on March 10, 2026. Although the GTCR Reporting Persons may be deemed to beneficially own the Common Stock held of record by the Warburg Pincus Investors as a result of the Stockholders Agreement, each GTCR Reporting Person expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Exchange Act) with respect to any shares of Common Stock other than the shares of Common Stock of the Issuer owned of record by such GTCR Reporting Person. The percentages used herein have been determined in accordance with footnote 2 below. Capitalized terms used herein are defined in Items 2(a) or 4 below.
(2) Calculated based on 284,392,079 shares of Common Stock outstanding as of February 17, 2026 as reported on the Issuer's final prospectus supplement, filed pursuant to Rule 424(b)(7) on March 5, 2026.
SCHEDULE 13G
CUSIP Number(s):
1
Names of Reporting Persons
GTCR FUND XI/C LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
31,838,253.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
2,546,564.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
31,838,253.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
11.2 %
12
Type of Reporting Person (See Instructions)
PN
Comment for Type of Reporting Person: (1) As more fully described in Item 4 of this Amendment No. 6 to Schedule 13G, the GTCR Investors are party to a Stockholders Agreement with the Warburg Pincus Investors and certain other holders of Common Stock of the Issuer. The GTCR Investors, together with the Warburg Pincus Investors, hold an aggregate total of 31,838,253 shares of Common Stock of the Issuer (approximately 11.2% of the outstanding shares of Common Stock of the Issuer), of which 19,102,952 shares of Common Stock are publicly reported as being owned by the Warburg Pincus Investors in such entities' Form 4, filed with the Commission on March 10, 2026. Although the GTCR Reporting Persons may be deemed to beneficially own the Common Stock held of record by the Warburg Pincus Investors as a result of the Stockholders Agreement, each GTCR Reporting Person expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Exchange Act) with respect to any shares of Common Stock other than the shares of Common Stock of the Issuer owned of record by such GTCR Reporting Person. The percentages used herein have been determined in accordance with footnote 2 below. Capitalized terms used herein are defined in Items 2(a) or 4 below.
(2) Calculated based on 284,392,079 shares of Common Stock outstanding as of February 17, 2026 as reported on the Issuer's final prospectus supplement, filed pursuant to Rule 424(b)(7) on March 5, 2026.
SCHEDULE 13G
CUSIP Number(s):
1
Names of Reporting Persons
GTCR CO-INVEST XI LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
31,838,253.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
81,010.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
31,838,253.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
11.2 %
12
Type of Reporting Person (See Instructions)
PN
Comment for Type of Reporting Person: (1) As more fully described in Item 4 of this Amendment No. 6 to Schedule 13G, the GTCR Investors are party to a Stockholders Agreement with the Warburg Pincus Investors and certain other holders of Common Stock of the Issuer. The GTCR Investors, together with the Warburg Pincus Investors, hold an aggregate total of 31,838,253 shares of Common Stock of the Issuer (approximately 11.2% of the outstanding shares of Common Stock of the Issuer), of which 19,102,952 shares of Common Stock are publicly reported as being owned by the Warburg Pincus Investors in such entities' Form 4, filed with the Commission on March 10, 2026. Although the GTCR Reporting Persons may be deemed to beneficially own the Common Stock held of record by the Warburg Pincus Investors as a result of the Stockholders Agreement, each GTCR Reporting Person expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Exchange Act) with respect to any shares of Common Stock other than the shares of Common Stock of the Issuer owned of record by such GTCR Reporting Person. The percentages used herein have been determined in accordance with footnote 2 below. Capitalized terms used herein are defined in Items 2(a) or 4 below.
(2) Calculated based on 284,392,079 shares of Common Stock outstanding as of February 17, 2026 as reported on the Issuer's final prospectus supplement, filed pursuant to Rule 424(b)(7) on March 5, 2026.
SCHEDULE 13G
CUSIP Number(s):
1
Names of Reporting Persons
GTCR PARTNERS XI/A&C LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
31,838,253.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
12,654,291.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
31,838,253.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
11.2 %
12
Type of Reporting Person (See Instructions)
PN
Comment for Type of Reporting Person: (1) As more fully described in Item 4 of this Amendment No. 6 to Schedule 13G, the GTCR Investors are party to a Stockholders Agreement with the Warburg Pincus Investors and certain other holders of Common Stock of the Issuer. The GTCR Investors, together with the Warburg Pincus Investors, hold an aggregate total of 31,838,253 shares of Common Stock of the Issuer (approximately 11.2% of the outstanding shares of Common Stock of the Issuer), of which 19,102,952 shares of Common Stock are publicly reported as being owned by the Warburg Pincus Investors in such entities' Form 4, filed with the Commission on March 10, 2026. Although the GTCR Reporting Persons may be deemed to beneficially own the Common Stock held of record by the Warburg Pincus Investors as a result of the Stockholders Agreement, each GTCR Reporting Person expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Exchange Act) with respect to any shares of Common Stock other than the shares of Common Stock of the Issuer owned of record by such GTCR Reporting Person. The percentages used herein have been determined in accordance with footnote 2 below. Capitalized terms used herein are defined in Items 2(a) or 4 below.
(2) Calculated based on 284,392,079 shares of Common Stock outstanding as of February 17, 2026 as reported on the Issuer's final prospectus supplement, filed pursuant to Rule 424(b)(7) on March 5, 2026.
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Sotera Health Co.
(b)
Address of issuer's principal executive offices:
The Company's principal executive offices are located at 9100 South Hills Blvd, Suite 300, Broadview Heights, OH, 44147.
Item 2.
(a)
Name of person filing:
This Amendment No. 6 to Schedule 13G is being filed jointly by (i) GTCR Investment XI LLC, a Delaware limited liability company ("Investment XI"), (ii) GTCR Fund XI/A LP, a Delaware limited partnership ("Fund XI/A"), (iii) GTCR Fund XI/C LP, a Delaware limited partnership ("Fund XI/C"), (iv) 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 or GTCR Investors"), and (v) GTCR Partners XI/A&C LP, a Delaware limited partnership ("Partners XI/A&C"), and which is the general partner of each of Fund XI/A and Fund XI/C. Investment XI 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, 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. The GTCR XI Funds, Partners XI/A&C and Investment XI are collectively referred to herein as the "GTCR Reporting Persons".
(b)
Address or principal business office or, if none, residence:
The principal business address of each of the GTCR Reporting Persons is 300 North LaSalle Street, Suite 5600, Chicago, IL 60654.
(c)
Citizenship:
(d)
Title of class of securities:
Common Stock, par value $0.01 per share
(e)
CUSIP No.:
83601L102
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
The information required by Items 4(a)-(c) is set forth in Rows 5-11 of the cover page hereto for each GTCR Reporting Person and is incorporated herein by reference for each such GTCR Reporting Person.
On November 19, 2020, (i) the Issuer, (ii) Warburg Pincus Private Equity XI, L.P., Warburg Pincus Private Equity XI-B, L.P., Warburg Pincus Private Equity XI-C, L.P., WP XI Partners, L.P. and Bull Co-Invest, L.P. (collectively, the "Warburg Pincus Sponsors" or "Warburg Pincus Investors"), (iii) the GTCR XI Funds and (iv) certain other holders of Common Stock of the issuer ( the "Other Investors"), entered into a Stockholders Agreement (the "Stockholders Agreement"). The Stockholders Agreement sets forth certain governance arrangements with respect to the Issuer, transfer restrictions on Other Investors and indemnification matters. Pursuant to the Stockholders Agreement, each of the Warburg Pincus Sponsors and the GTCR XI Funds has agreed to vote the shares of Common Stock of the Issuer that each holds of record in a certain manner on matters related to the election of certain directors appointed by the Warburg Pincus Sponsors and the GTCR XI Funds. The Warburg Pincus Sponsors and the GTCR XI Funds hold an aggregate total of 31,838,253 shares of Common Stock of the Issuer (approximately 11.2% of the outstanding shares of Common Stock of the Issuer), including 12,735,301 shares of Common Stock owned by the GTCR XI Funds and 19,102,952 shares of Common Stock owned by the Warburg Pincus Sponsors. The GTCR Reporting Persons are not entitled to any rights as a stockholder of the Issuer with respect to the shares of Common Stock of the Issuer beneficially owned by the Other Investors or the Warburg Pincus Sponsors except as expressly set forth in the Stockholders Agreement and the GTCR Reporting Persons do not have dispositive power over the Common Stock owned by the Warburg Pincus Sponsors. Each GTCR Reporting Person and each of the individual members of the GTCR Board of Managers expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Exchange Act) with respect to any shares of Common Stock of the Issuer other than the shares of Common Stock of the Issuer owned of record by a GTCR Reporting Person. The number of shares of Common Stock of the Issuer owned by each GTCR Reporting Person as set forth in Rows 5 - 11 of their respective cover pages to this Schedule 13G does not reflect the aggregate shares of Common Stock of the Issuer owned by the Other Investors.
The aggregate total of 19,102,952 shares of Common Stock of the Issuer indicated in this Amendment No. 6 to Schedule 13G as being beneficially owned by the Warburg Pincus Sponsors is derived from the Warburg Pincus Sponsors' Form 4, filed with the Commission on March 10, 2026, and is not purported to be an accurate representation of the Warburg Pincus Sponsors' beneficial ownership as of the date of this Amendment No. 6 to Schedule 13G. The Warburg Pincus Sponsors are responsible for reporting their beneficial ownership of shares of Common Stock of the Issuer on their own behalf, and the GTCR Reporting Persons disclaim responsibility for reporting the shares of Common Stock of the Issuer beneficially owned by the Warburg Pincus Sponsors.
The percentages used herein are calculated based on 284,392,079 shares of Common Stock outstanding as of February 17, 2026 as reported on the Issuer's final prospectus supplement, filed pursuant to Rule 424(b)(7) on March 5, 2026.
(b)
Percent of class:
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
(ii) Shared power to vote or to direct the vote:
(iii) Sole power to dispose or to direct the disposition of:
(iv) Shared power to dispose or to direct the disposition of:
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
If a group has filed this schedule pursuant to §240.13d-1(b)(1)(ii)(J), so indicate under Item 3(j) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to §240.13d-1(c) or §240.13d-1(d), attach an exhibit stating the identity of each member of the group.
(1) The GTCR Reporting Persons are making this single, joint filing because they may be deemed to constitute a "group" within the meaning of the Exchange Act. The joint filing agreement among the GTCR Reporting Persons to file this Amendment No. 6 to Schedule 13G jointly in accordance with Rule 13d-1(k) of the Exchange Act is incorporated by reference as Exhibit 99.1.
(2) Each GTCR Reporting Person expressly disclaims beneficial ownership (within the meaning of Rule 13d-3 of the Exchange Act) with respect to any shares of Common Stock of the issuer other than the shares of Common Stock of the issuer owned of record by such GTCR Reporting Person.
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
Not Applicable
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
GTCR INVESTMENT XI LLC
Signature:
/s/ Jeffrey Wright
Name/Title:
Jeffrey Wright, Chief Legal Officer
Date:
03/10/2026
GTCR FUND XI/A LP
Signature:
/s/ Jeffrey Wright
Name/Title:
Jeffrey Wright, Chief Legal Officer of GTCR Invest. XI LLC, the general partner of GTCR Partners XI/A&C LP, the general partner of GTCR FUND XI/A LP
Date:
03/10/2026
GTCR FUND XI/C LP
Signature:
/s/ Jeffrey Wright
Name/Title:
Jeffrey Wright, Chief Legal Officer of GTCR Invest. XI LLC, the general partner of GTCR Partners XI/A&C LP, the general partner of GTCR FUND XI/C LP
Date:
03/10/2026
GTCR CO-INVEST XI LP
Signature:
/s/ Jeffrey Wright
Name/Title:
Jeffrey Wright, Chief Legal Officer of GTCR Investment XI LLC, the general partner of GTCR CO-INVEST XI LP
Date:
03/10/2026
GTCR PARTNERS XI/A&C LP
Signature:
/s/ Jeffrey Wright
Name/Title:
Jeffrey Wright, Chief Legal Officer of GTCR Investment XI LLC, the general partner of GTCR PARTNERS XI/A&C LP
Date:
03/10/2026
Comments accompanying signature: Exhibit 99.1 Agreement of Joint Filing as required by Rule 13d-1(k)(1) under the Act.*
* Incorporated herein by reference to the Agreement of Joint Filing by GTCR Investment XI LLC, GTCR Fund XI/A LP, GTCR Fund XI/C LP, GTCR Co-Invest XI LP and GTCR Partners XI/A&C LP dated as of February 11, 2022, which was previously filed with the Commission as Exhibit A to Amendment No. 1 to Schedule 13G filed by GTCR Investment XI LLC, GTCR Fund XI/A LP, GTCR Fund XI/C LP, GTCR Co-Invest XI LP and GTCR Partners XI/A&C LP on February 11, 2022 with respect to the shares of common stock of Sotera Health Co.
What stake does GTCR report in Sotera Health (SHC)?
GTCR reports shared voting power over 31,838,253 shares, equal to about 11.2% of the class based on February 17, 2026. The figure is the combined total held by GTCR and Warburg Pincus under a Stockholders Agreement.
Does GTCR claim direct beneficial ownership of all 31,838,253 shares?
No. GTCR disclaims beneficial ownership of shares held of record by the Warburg Pincus investors and limits its claimed ownership to shares each GTCR entity owns of record, per the filing language.
How was the outstanding share base determined in the filing?
The percentage uses 284,392,079 shares outstanding as of February 17, 2026, per the issuer's final prospectus supplement filed under Rule 424(b)(7) on March 5, 2026.
What governance arrangements are referenced in the filing?
The filing references a Stockholders Agreement entered on November 19, 2020 that sets voting protocols for director elections and includes transfer restrictions and indemnification terms among the GTCR and Warburg Pincus investors.
Will this filing tell me whether GTCR plans to sell or buy more SHC shares?
No. The amendment is an ownership disclosure describing current shared voting power and the Stockholders Agreement; it does not state any planned purchases, sales, or cash‑flow treatment.
