RA Capital Management, L.P. and affiliated reporting persons reported beneficial ownership of 1,182,624 shares of Adicet Bio, Inc. common stock. The filing states the Fund also holds pre-funded warrants exercisable for up to 1,152,833 additional shares, but a Beneficial Ownership Blocker prevents exercise that would raise ownership above 9.99%. The percentage reported (12.3%) is calculated using 9,596,407 shares outstanding as of March 10, 2026. The filing discloses delegated voting and dispositive authority to RA Capital and includes standard disclaimers regarding beneficial ownership for Section 13(d) purposes.
Positive
None.
Negative
None.
Insights
Reporting persons show a concentrated stake and capped exercisability due to a 9.99% blocker.
The filing lists a direct holding of 1,182,624 shares and pre-funded warrants exercisable into 1,152,833 shares; exercise is limited by a provision that prevents exceeding 9.99%. Voting and disposition powers are delegated to RA Capital, which manages the Fund's portfolio.
Implications hinge on the blocker: the Fund cannot increase ownership above 9.99% unless the blocker is removed. Subsequent filings would show any change in exercise rights or ownership percentages.
Key Figures
Direct shares held:1,182,624 sharesPre-funded warrants exercisable:1,152,833 sharesBeneficial ownership cap:9.99%+2 more
5 metrics
Direct shares held1,182,624 sharesFund directly holds these shares
Pre-funded warrants exercisable1,152,833 shareswarrants exercisable into common stock
Beneficial ownership cap9.99%Beneficial Ownership Blocker prevents exercise above this level
Shares outstanding used9,596,407 sharesas of <date>March 10, 2026</date>
Reported ownership percentage12.3%percentage based on outstanding shares as of March 10, 2026
"the Fund directly holds (i) 1,182,624 shares, and (ii) pre-funded warrants exercisable"
Pre-funded warrants are financial instruments that give investors the right to purchase a company's stock at a set price, but with most or all of the purchase price paid upfront. They function like a coupon or gift card for stock, allowing investors to buy shares later at a fixed price, which can be beneficial if they want to avoid future price increases. This makes them important for investors seeking flexibility and certainty in their investment plans.
Beneficial Ownership Blockerregulatory
"The Pre-Funded Warrants contain a provision (the "Beneficial Ownership Blocker")"
Section 13(d)regulatory
"may be deemed a beneficial owner, for purposes of Section 13(d) of the Act"
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 3)
Adicet Bio, Inc.
(Name of Issuer)
Common Stock, par value $0.0001 per share
(Title of Class of Securities)
007002207
(CUSIP Number)
02/17/2026
(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)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
007002207
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
1,182,624.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,182,624.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,182,624.00
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)
12.3 %
12
Type of Reporting Person (See Instructions)
IA, PN
SCHEDULE 13G
CUSIP Number(s):
007002207
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
1,182,624.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,182,624.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,182,624.00
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)
12.3 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
CUSIP Number(s):
007002207
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
1,182,624.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,182,624.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,182,624.00
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)
12.3 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
CUSIP Number(s):
007002207
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
1,182,624.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,182,624.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,182,624.00
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)
12.3 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Adicet Bio, Inc.
(b)
Address of issuer's principal executive offices:
131 Dartmouth Street, Floor 3, Boston, MA, 02116.
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
Rajeev Shah
RA Capital Healthcare Fund, L.P. (the "Fund")
The Reporting Persons expressly disclaim status as a "group" for purposes of this Schedule 13G/A.
(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.:
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/A 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) 1,182,624 shares of common stock, and (ii) pre-funded warrants (the "Pre- Funded Warrants") exercisable for an aggregate of up to 1,152,833 shares of common stock. The Pre-Funded Warrants contain a provision (the "Beneficial Ownership Blocker"), which precludes the exercise of the Pre-Funded 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 Pre-Funded Warrants by virtue of the Beneficial Ownership Blocker.
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/A other than for the purpose of determining their obligations under Section 13(d) of the Act, and the filing of this Schedule 13G/A 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:
Row 11 of each Reporting Person's cover page to this Schedule 13G/A sets forth the percentages of the shares of common stock of the Issuer beneficially owned by such Reporting Person and is incorporated by reference. The percentage set forth in each row 11 is based upon 9,596,407 shares of common stock outstanding as of March 10, 2026, as reported in the Issuer's Annual Report on Form 10-K filed with the Securities and Exchange Commission (the "SEC") on March 12, 2026.
(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/A 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/A 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/A 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/A 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:
04/13/2026
Peter Kolchinsky
Signature:
/s/ Peter Kolchinsky
Name/Title:
Peter Kolchinsky
Date:
04/13/2026
Rajeev Shah
Signature:
/s/ Rajeev Shah
Name/Title:
Rajeev Shah
Date:
04/13/2026
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
Date:
04/13/2026
Exhibit Information
Exhibit 99.1 Joint Filing Agreement (incorporated by reference to Exhibit 1 to Schedule 13G/A filed on November 14, 2024)
What stake does RA Capital report in Adicet Bio (ACET)?
RA Capital reports beneficial ownership of 1,182,624 shares. The filing also lists pre-funded warrants exercisable for up to 1,152,833 additional shares; exercise is blocked to prevent ownership above 9.99%.
How is the 9.99% Beneficial Ownership Blocker applied for ACET?
The Pre-Funded Warrants contain a Beneficial Ownership Blocker that prevents exercise if exercise would result in ownership exceeding 9.99%. The filing states the Fund is currently prohibited from exercising the warrants by this provision.
What basis is used for the ownership percentage in the ACET filing?
The percentage (12.3%) is calculated using 9,596,407 shares outstanding as of March 10, 2026. That share count is cited from the company's Annual Report on Form 10-K filed March 12, 2026.
Who has voting and dispositive power over the reported ACET shares?
RA Capital serves as investment adviser and holds sole voting and dispositive power over the Fund's portfolio securities, per the filing; the Fund delegated those powers to RA Capital and disclaims beneficial ownership for certain Section 13(d) purposes.
Do the reporting persons claim to be a group for ACET purposes?
The Reporting Persons expressly disclaim status as a "group" in the amendment. The filing lists RA Capital, the Fund, and individuals but states they are not a group for the referenced purpose.
