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

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)

VIGIL NEUROSCIENCE, INC.

(Name of Issuer)

Common Stock, $0.0001 par value per share

(Title of Class of Securities)

92673K108

(CUSIP Number)

Ommer Chohan, CFO
300 Technology Square, 8th Floor,
Cambridge, MA, 02139
(857) 201-2700

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

08/05/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 92673K108

1

Name of reporting person

Atlas Venture Fund XII, L.P.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

WC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0.0 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP No. 92673K108

1

Name of reporting person

Atlas Venture Associates XII, L.P.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0.0 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP No. 92673K108

1

Name of reporting person

Atlas Venture Associates XII, LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0.0 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

CUSIP No. 92673K108

1

Name of reporting person

Atlas Venture Opportunity Fund I, L.P.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

WC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0.0 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP No. 92673K108

1

Name of reporting person

Atlas Venture Associates Opportunity I, L.P.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0.0 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP No. 92673K108

1

Name of reporting person

Atlas Venture Associates Opportunity I, LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0.0 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock, $0.0001 par value per share
(b)	Name of Issuer: VIGIL NEUROSCIENCE, INC.
(c)	Address of Issuer's Principal Executive Offices: 100 Forge Road, Suite 700, Watertown, MASSACHUSETTS , 02472.
Item 1 Comment: Item 1 of the Statement is amended and supplemented as follows: This Amendment No. 1 (this "Amendment No. 1" or this "Schedule 13D/A") amends and supplements the statement on Schedule 13D originally filed with the Securities and Exchange Commission (the "SEC") on January 21, 2022 (as amended, the "Statement") by the Reporting Persons. Unless otherwise defined herein, capitalized terms used in this Amendment No. 1 shall have the meanings ascribed to them in the Statement. Unless amended or supplemented below, the information in the Statement remains unchanged.
Item 4.	Purpose of Transaction
	Item 4 of the Statement is hereby amended and supplemented as follows: On May 21, 2025, the Issuer entered into an Agreement and Plan of Merger (the "Merger Agreement") with Sanofi, a French societe anonyme ("Parent" or "Sanofi"), and Vesper Acquisition Sub Inc., a Delaware corporation and a wholly-owned subsidiary of Parent ("Merger Sub"), pursuant to which, Merger Sub would merge with and into the Issuer (the "Merger"), with the Issuer surviving the merger as a wholly-owned subsidiary of Parent. On August 4, 2025, at a special meeting of stockholders of the Issuer, the Issuer's stockholders voted to adopt the Merger Agreement. On August 5, 2025, the Merger closed and each share of the Issuer's Common Stock issued and outstanding, including all of the shares of Common Stock owned by the Reporting Persons, was converted into the right to receive (i) $8.00 per share of Common Stock in cash, without interest plus (ii) one contingent value right, representing the right to receive $2.00 payable in cash, conditioned upon satisfaction of a certain clinical milestone.
Item 5.	Interest in Securities of the Issuer
(a)	As of the date hereof, the Reporting Persons no longer beneficially owns any securities of the Issuer or any percentage of the Issuer's outstanding Common Stock.
(b)	As of the date hereof, the Reporting Persons no longer beneficially owns any securities of the Issuer.
(c)	Except as descried herein, none of the Reporting Persons have purchased or sold any shares of Common Stock during the past 60 days.
(d)	No other person is known to have the right to receive or the power to direct the receipt of dividends from, or any proceeds from the sale of, the shares of Common Stock beneficially owned by any of the Reporting Persons.
(e)	The Reporting Persons ceased to be the beneficial owners of more than five percent of the Common Stock on August 5, 2025 by virtue of the closing of the Merger.
Item 7.	Material to be Filed as Exhibits.
	Exhibit 99.1 - Joint Filing Agreement

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.

Atlas Venture Fund XII, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates XII, L.P., its general partner, By: Atlas Venture Associates XII, LLC, its general partner, By: Ommer Chohan, its CFO
Date:	08/07/2025

Atlas Venture Associates XII, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates XII, LLC, its general partner, By: Ommer Chohan, its CFO
Date:	08/07/2025

Atlas Venture Associates XII, LLC

Signature:	/s/ Ommer Chohan
Name/Title:	Ommer Chohan, CFO
Date:	08/07/2025

Atlas Venture Opportunity Fund I, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity I L.P., its GP, By: Atlas Venture Associates Opportunity I LLC, its GP, By: Ommer Chohan, its CFO
Date:	08/07/2025

Atlas Venture Associates Opportunity I, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity I LLC, its GP, By: Ommer Chohan, its CFO
Date:	08/07/2025

Atlas Venture Associates Opportunity I, LLC

Signature:	/s/ Ommer Chohan
Name/Title:	Ommer Chohan, CFO
Date:	08/07/2025