Century Therapeutics, Inc. received a Schedule 13G from RA Capital Management and related parties reporting a significant passive ownership position. RA Capital Healthcare Fund directly holds 17,754,430 shares of common stock, plus pre-funded warrants exercisable for up to 8,332,526 shares and additional warrants exercisable for up to 13,043,478 shares of common stock. A beneficial ownership blocker in these warrants limits the group’s exercisability so that total beneficial ownership does not exceed 9.99% of Century’s common stock, which is currently 17,944,649 shares.
The 9.99% figure is calculated using 87,405,311 shares outstanding as of November 25, 2025, plus 92,030,595 shares issued in a January 9, 2026 private placement and 190,219 shares issuable upon warrant exercise. RA Capital Management, L.P., RA Capital Healthcare Fund, L.P., and individuals Peter Kolchinsky and Rajeev Shah report shared voting and dispositive power over these securities and certify they are not holding them to change or influence control of Century Therapeutics.
Positive
None.
Negative
None.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Century Therapeutics, Inc.
(Name of Issuer)
Common Stock, par value $0.0001 per share
(Title of Class of Securities)
15673T100
(CUSIP Number)
01/09/2026
(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 No.
15673T100
1
Names of Reporting Persons
RA Capital Management, L.P.
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
17,944,649.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
17,944,649.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
17,944,649.00
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)
9.9 %
12
Type of Reporting Person (See Instructions)
IA, PN
SCHEDULE 13G
CUSIP No.
15673T100
1
Names of Reporting Persons
Peter Kolchinsky
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
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
17,944,649.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
17,944,649.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
17,944,649.00
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)
9.9 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
CUSIP No.
15673T100
1
Names of Reporting Persons
Rajeev Shah
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
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
17,944,649.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
17,944,649.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
17,944,649.00
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)
9.9 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
CUSIP No.
15673T100
1
Names of Reporting Persons
RA Capital Healthcare Fund, L.P.
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
17,944,649.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
17,944,649.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
17,944,649.00
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)
9.9 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Century Therapeutics, Inc.
(b)
Address of issuer's principal executive offices:
25 North 38th Street, 11th Floor, Philadelphia, PA, 19104.
Item 2.
(a)
Name of person filing:
The names of the persons filing this report (collectively, the "Reporting Persons") are:
RA Capital Management, L.P. ("RA Capital")
Peter Kolchinsky ("Dr. Kolchinsky")
Rajeev Shah ("Mr. Shah")
RA Capital Healthcare Fund, L.P. (the "Fund")
The Reporting Persons expressly disclaim status as a "group" for purposes of this Schedule 13G.
(b)
Address or principal business office or, if none, residence:
The address of the principal business office of each of the Reporting Persons is:
c/o RA Capital Management, L.P., 200 Berkeley Street, 18th Floor, Boston MA 02116
(c)
Citizenship:
RA Capital and the Fund are Delaware limited partnerships.
Dr. Kolchinsky and Mr. Shah are United States citizens.
(d)
Title of class of securities:
Common Stock, par value $0.0001 per share
(e)
CUSIP No.:
15673T100
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:
Row 9 of each Reporting Person's cover page to this Schedule 13G sets forth the aggregate number of shares of common stock of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
The Fund directly holds (i) 17,754,430 shares of common stock; (ii) pre-funded warrants (the "Pre-Funded Warrants") exercisable for up to 8,332,526 shares of common stock; and (iii) warrants (the "Common Warrants" and, together with the Pre-Funded Warrants, the "Warrants") exercisable for up to 13,043,478 shares of common stock. Each of the Warrants contains a provision (the "Beneficial Ownership Blockers") which precludes exercise of the Warrants to the extent that, following exercise, the Fund, together with its affiliates and other attribution parties, would own more than 9.99% of the common stock outstanding. The Fund is currently prohibited from exercising the Warrants to the extent that such exercise would result in the Reporting Persons' beneficial ownership of more than 17,944,649 shares of common stock.
RA Capital Healthcare Fund GP, LLC is the general partner of the Fund. The general partner of RA Capital is RA Capital Management GP, LLC, of which Dr. Kolchinsky and Mr. Shah are the controlling persons. RA Capital serves as investment adviser for the Fund and may be deemed a beneficial owner, for purposes of Section 13(d) of the Act, of any securities of the Issuer held by the Fund. The Fund has delegated to RA Capital the sole power to vote and the sole power to dispose of all securities held in the Fund's portfolio, including the shares of the Issuer's common stock reported herein. Because the Fund has divested voting and investment power over the reported securities it holds and may not revoke that delegation on less than 61 days' notice, the Fund disclaims beneficial ownership of the securities it holds for purposes of Section 13(d) of the Act. As managers of RA Capital, Dr. Kolchinsky and Mr. Shah may be deemed beneficial owners, for purposes of Section 13(d) of the Act, of any securities of the Issuer beneficially owned by RA Capital. RA Capital, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of the securities reported in this Schedule 13G other than for the purpose of determining their obligations under Section 13(d) of the Act, and the filing of this Schedule 13G shall not be deemed an admission that either RA Capital, Dr. Kolchinsky, or Mr. Shah is the beneficial owner of such securities for any other purpose.
(b)
Percent of class:
Due to the Beneficial Ownership Blocker listed in the Warrants, each Reporting Person's beneficial ownership percentage is 9.99%. Such percentage is based upon the sum of (i) 87,405,311 shares of common stock outstanding as of November 25, 2025, as reported in the Issuer's definitive proxy statement, filed with the Securities and Exchange Commission (the "SEC") on December 2, 2025; (ii) 92,030,595 shares of common stock issued in the private placement of equity securities by the Issuer that closed on January 9, 2026; and (iii) 190,219 shares of common stock issuable upon the exercise of the Warrants. Due to field limitations of the EDGAR filing system, the percentages listed in Row 11 of the Reporting Persons' cover pages have been rounded down to 9.9%.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
Row 5 of each Reporting Person's cover page to this Schedule 13G sets forth the sole power to vote or to direct the vote of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
(ii) Shared power to vote or to direct the vote:
Row 6 of each Reporting Person's cover page to this Schedule 13G sets forth the shared power to vote or to direct the vote of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
(iii) Sole power to dispose or to direct the disposition of:
Row 7 of each Reporting Person's cover page to this Schedule 13G sets forth the sole power to dispose or to direct the disposition of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
(iv) Shared power to dispose or to direct the disposition of:
Row 8 of each Reporting Person's cover page to this Schedule 13G sets forth the shared power to dispose or to direct the disposition of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
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.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
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.
RA Capital Management, L.P.
Signature:
/s/ Peter Kolchinsky
Name/Title:
By Peter Kolchinsky, Authorized Signatory
Date:
01/16/2026
Peter Kolchinsky
Signature:
/s/ Peter Kolchinsky
Name/Title:
Peter Kolchinsky
Date:
01/16/2026
Rajeev Shah
Signature:
/s/ Rajeev Shah
Name/Title:
Rajeev Shah
Date:
01/16/2026
RA Capital Healthcare Fund, L.P.
Signature:
/s/ Peter Kolchinsky
Name/Title:
By RA Capital Healthcare Fund GP, LLC, its General Partner, By Peter Kolchinsky, Manager
What ownership stake in Century Therapeutics (IPSC) does RA Capital report?
RA Capital Management, RA Capital Healthcare Fund, Peter Kolchinsky, and Rajeev Shah report beneficial ownership of 17,944,649 shares of Century Therapeutics common stock, representing 9.99% of the outstanding class.
Which securities related to Century Therapeutics does RA Capital’s fund hold?
RA Capital Healthcare Fund directly holds 17,754,430 shares of Century Therapeutics common stock, pre-funded warrants exercisable for up to 8,332,526 shares, and additional warrants exercisable for up to 13,043,478 shares of common stock.
How is the 9.99% ownership of Century Therapeutics (IPSC) calculated?
The 9.99% beneficial ownership is based on 87,405,311 shares outstanding as of November 25, 2025, plus 92,030,595 shares issued in a private placement that closed on January 9, 2026 and 190,219 shares issuable upon warrant exercise.
What is the purpose of the beneficial ownership blocker in RA Capital’s warrants?
Each warrant includes a Beneficial Ownership Blocker that prevents exercise to the extent it would cause the RA Capital Healthcare Fund, together with its affiliates and attribution parties, to own more than 9.99% of Century Therapeutics’ outstanding common stock.
Do the reporting persons intend to influence control of Century Therapeutics?
The reporting persons certify that the securities of Century Therapeutics were not acquired and are not held for the purpose of changing or influencing control of the issuer, consistent with a Schedule 13G passive ownership filing.
Who are the reporting persons on this Century Therapeutics Schedule 13G?
The reporting persons are RA Capital Management, L.P., RA Capital Healthcare Fund, L.P., and individuals Peter Kolchinsky and Rajeev Shah, each reporting shared voting and dispositive power over the same 17,944,649 shares.
What voting and dispositive powers do RA Capital and its principals have over IPSC shares?
For Century Therapeutics shares, the reporting persons disclose 0 sole voting and dispositive power and 17,944,649 shares of shared voting and dispositive power, delegated through RA Capital’s role as investment adviser to the fund.
