[SCHEDULE 13G/A] Vigil Neuroscience, Inc. SEC Filing

Rhea-AI Filing Summary

Vigil Neuroscience, Inc. Schedule 13G/A filed by a group of related entities led by Biotechnology Value Fund and Mark N. Lampert reports that, as of the close of business on June 30, 2025, the Reporting Persons no longer beneficially owned any shares of Vigil Neuroscience common stock (CUSIP 92673K108). The filing lists each reporting entity, their jurisdictions (mostly Delaware, some Cayman Islands), the reporting address for BVF entities, and confirms zero sole or shared voting and dispositive power for all listed persons. The statement is signed by Mark N. Lampert on behalf of the reporting entities on August 14, 2025.

Positive

• Reporting Persons disclosed they no longer beneficially own any shares of VIGL as of June 30, 2025

Negative

• The group's aggregate ownership is reported as 0%, indicating BVF-affiliated entities hold no stake in Vigil Neuroscience

Insights

Financial Analyst

TL;DR: Key institutional holders report 0% ownership, removing a prior disclosed stake in VIGL.

The Schedule 13G/A is a clear, rule-compliant update: multiple BVF-related entities and Mark N. Lampert state they no longer beneficially own any Vigil Neuroscience shares as of June 30, 2025. This disclosure provides certainty about the absence of BVF-affiliated ownership and voting influence. The filing is administrative and does not include financial metrics, transactions, or reasons for the disposition, limiting further analysis.

Corporate Governance Expert

TL;DR: Governance impact is limited; previously disclosed group now reports no holdings or voting power.

The document identifies the reporting group members, their organizational jurisdictions, and confirms zero sole or shared voting/dispositive power. From a governance perspective, the filing signals that these entities no longer have the ability to influence board or shareholder actions through holdings. The certification attests the absence of intent to change control. No additional governance actions or agreements are disclosed.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 2)

Vigil Neuroscience, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

92673K108

(CUSIP Number)

06/30/2025

(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. 92673K108

1

Names of Reporting Persons

BIOTECHNOLOGY VALUE 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BVF I GP 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BIOTECHNOLOGY VALUE FUND II 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BVF II GP 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

Biotechnology Value Trading Fund OS 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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BVF Partners OS Ltd.

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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BVF GP HOLDINGS 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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BVF PARTNERS L P/IL

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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

IA, PN

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

BVF INC/IL

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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13G

CUSIP No. 92673K108

1

Names of Reporting Persons

LAMPERT MARK N

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 0.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

0.00

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)

0 %

12

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Vigil Neuroscience, Inc.
(b)	Address of issuer's principal executive offices: 100 Forge Road, Suite 700, Watertown, Massachusetts 02472
Item 2.
(a)	Name of person filing: Biotechnology Value Fund, L.P. ("BVF") BVF I GP LLC ("BVF GP") Biotechnology Value Fund II, L.P. ("BVF2") BVF II GP LLC ("BVF2 GP") Biotechnology Value Trading Fund OS LP ("Trading Fund OS") BVF Partners OS Ltd. ("Partners OS") BVF GP Holdings LLC ("BVF GPH") BVF Partners L.P. ("Partners") BVF Inc. Mark N. Lampert ("Mr. Lampert") Each of the foregoing is referred to as a "Reporting Person" and collectively as the "Reporting Persons."
(b)	Address or principal business office or, if none, residence: Biotechnology Value Fund, L.P. 44 Montgomery St., 40th Floor San Francisco, California 94104 BVF I GP LLC 44 Montgomery St., 40th Floor San Francisco, California 94104 Biotechnology Value Fund II, L.P. 44 Montgomery St., 40th Floor San Francisco, California 94104 BVF II GP LLC 44 Montgomery St., 40th Floor San Francisco, California 94104 Biotechnology Value Trading Fund OS LP PO Box 309 Ugland House Grand Cayman, KY1-1104 Cayman Islands BVF Partners OS Ltd. PO Box 309 Ugland House Grand Cayman, KY1-1104 Cayman Islands BVF GP Holdings LLC 44 Montgomery St., 40th Floor San Francisco, California 94104 BVF Partners L.P. 44 Montgomery St., 40th Floor San Francisco, California 94104 BVF Inc. 44 Montgomery St., 40th Floor San Francisco, California 94104 Mark N. Lampert 44 Montgomery St., 40th Floor San Francisco, California 94104
(c)	Citizenship: Biotechnology Value Fund, L.P. Delaware BVF I GP LLC Delaware Biotechnology Value Fund II, L.P. Delaware BVF II GP LLC Delaware Biotechnology Value Trading Fund OS LP Cayman Islands BVF Partners OS Ltd. Cayman Islands BVF GP Holdings LLC Delaware BVF Partners L.P. Delaware BVF Inc. Delaware Mark N. Lampert United States
(d)	Title of class of securities: Common Stock, par value $0.0001 per share
(e)	CUSIP No.: 92673K108
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: As of the close of business on June 30, 2025, the Reporting Persons no longer beneficially owned any securities of the Issuer.
(b)	Percent of class: As of the close of business on June 30, 2025, the Reporting Persons no longer beneficially owned any securities of the Issuer.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: See Cover Pages Items 5-9.
	(ii) Shared power to vote or to direct the vote: See Cover Pages Items 5-9.
	(iii) Sole power to dispose or to direct the disposition of: See Cover Pages Items 5-9.
	(iv) Shared power to dispose or to direct the disposition of: See Cover Pages Items 5-9.
Item 5.	Ownership of 5 Percent or Less of a Class.
	Ownership of 5 percent or less of a class
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.
	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. See Exhibit 99.1 to the Schedule 13G filed by the Reporting Persons with the Securities and Exchange Commission on August 26, 2022.
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.

BIOTECHNOLOGY VALUE FUND L P

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BVF I GP LLC

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BIOTECHNOLOGY VALUE FUND II LP

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BVF II GP LLC

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

Biotechnology Value Trading Fund OS LP

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BVF Partners OS Ltd.

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BVF GP HOLDINGS LLC

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BVF PARTNERS L P/IL

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

BVF INC/IL

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert, Authorized Signatory
Date:	08/14/2025

LAMPERT MARK N

Signature:	/s/ Mark N. Lampert
Name/Title:	Mark N. Lampert
Date:	08/14/2025

FAQ

What did the Schedule 13G/A filed by BVF state about VIGL ownership?

The filing states the Reporting Persons no longer beneficially owned any Vigil Neuroscience (VIGL) common stock as of June 30, 2025.

Which entities filed the Schedule 13G/A for VIGL?

Reporting Persons include Biotechnology Value Fund, L.P.; BVF I GP LLC; Biotechnology Value Fund II, L.P.; BVF II GP LLC; Biotechnology Value Trading Fund OS LP; BVF Partners OS Ltd.; BVF GP Holdings LLC; BVF Partners L.P.; BVF Inc.; and Mark N. Lampert.

What voting or dispositive power do the reporting persons claim over VIGL shares?

The filing reports 0 sole voting power, 0 shared voting power, 0 sole dispositive power, and 0 shared dispositive power for each reporting person.

As of what date do the ownership statements apply in the VIGL Schedule 13G/A?

The ownership status is stated as of the close of business on June 30, 2025.

Who signed the Schedule 13G/A for the BVF reporting group?

Mark N. Lampert signed as Authorized Signatory for the reporting entities and individually, with signatures dated August 14, 2025.