Nan Fung Group details 6.7% Bolt Biotherapeutics (BOLT) ownership

Rhea-AI Filing Summary

Nal Fung–affiliated and Pivotal bioVenture entities filed Amendment No. 3 to report their beneficial ownership of Bolt Biotherapeutics common stock. Nan Fung Group Holdings Limited reports beneficial ownership of 128,119 shares, representing 6.7% of the common stock.

Several related entities, including Pivotal bioVenture Partners Fund I, L.P., report shared voting and dispositive power over 78,445 shares, or 4.1% of the class, while other Nan Fung life sciences entities report additional stakes ranging from 0.3% to 6.4%. The percentages are calculated against 1,919,441 shares outstanding as of the issuer’s Form 10‑Q filed November 12, 2025. The filing also notes that Mr. Kam Chung Leung directly owns 8,684 shares and that, except as described in an attached schedule, no reporting person has traded the stock in the past sixty days.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 3)

Bolt Biotherapeutics, Inc.

(Name of Issuer)

Common Stock, $0.00001 par value

(Title of Class of Securities)

097702203

(CUSIP Number)

Robert Hopfner
Pivotal bioVenture Partners Fund I UGP, 501 2nd Street, Suite 200
San Francisco, CA, 94107
(415) 697-1002

Louis Rambo
Proskauer Rose, LLP, 1001 Pennsylvania Avenue NW, Suite 600
Washington, DC, 20004-2533
(202) 416-6800

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

02/05/2026

(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. 097702203

1

Name of reporting person

Nan Fung Group Holdings Limited

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

VIRGIN ISLANDS, BRITISH

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 128,119.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 128,119.00

11

Aggregate amount beneficially owned by each reporting person

128,119.00

12

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

13

Percent of class represented by amount in Row (11)

6.7 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

NF Investment Holdings Limited

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

VIRGIN ISLANDS, BRITISH

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 128,119.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 128,119.00

11

Aggregate amount beneficially owned by each reporting person

128,119.00

12

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

13

Percent of class represented by amount in Row (11)

6.7 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Pivotal bioVenture Partners 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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 78,445.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 78,445.00

11

Aggregate amount beneficially owned by each reporting person

78,445.00

12

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

13

Percent of class represented by amount in Row (11)

4.1 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Pivotal bioVenture Partners Fund I G.P., 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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 78,445.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 78,445.00

11

Aggregate amount beneficially owned by each reporting person

78,445.00

12

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

13

Percent of class represented by amount in Row (11)

4.1 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Pivotal bioVenture Partners Fund I U.G.P. Ltd.

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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 78,445.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 78,445.00

11

Aggregate amount beneficially owned by each reporting person

78,445.00

12

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

13

Percent of class represented by amount in Row (11)

4.1 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Pivotal Partners Ltd

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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 78,445.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 78,445.00

11

Aggregate amount beneficially owned by each reporting person

78,445.00

12

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

13

Percent of class represented by amount in Row (11)

4.1 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Pivotal Life Sciences Holdings Limited

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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 78,445.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 78,445.00

11

Aggregate amount beneficially owned by each reporting person

78,445.00

12

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

13

Percent of class represented by amount in Row (11)

4.1 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Nan Fung Life Sciences Holdings Limited

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

VIRGIN ISLANDS, BRITISH

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 123,119.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 123,119.00

11

Aggregate amount beneficially owned by each reporting person

123,119.00

12

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

13

Percent of class represented by amount in Row (11)

6.4 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

Permwell Management Limited

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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 5,000.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 5,000.00

11

Aggregate amount beneficially owned by each reporting person

5,000.00

12

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

13

Percent of class represented by amount in Row (11)

0.3 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

NFLS Beta Limited

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

VIRGIN ISLANDS, BRITISH

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 44,674.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 44,674.00

11

Aggregate amount beneficially owned by each reporting person

44,674.00

12

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

13

Percent of class represented by amount in Row (11)

2.3 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

CUSIP No. 097702203

1

Name of reporting person

NFLS Platform Holdings Limited

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

CAYMAN ISLANDS

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 44,674.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 44,674.00

11

Aggregate amount beneficially owned by each reporting person

44,674.00

12

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

13

Percent of class represented by amount in Row (11)

2.3 %

14

Type of Reporting Person (See Instructions)

CO

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock, $0.00001 par value
(b)	Name of Issuer: Bolt Biotherapeutics, Inc.
(c)	Address of Issuer's Principal Executive Offices: 900 Chesapeake Drive, Redwood City, CALIFORNIA , 94063.
Item 5.	Interest in Securities of the Issuer
(a)	Items 5(a)-(c) of the Schedule 13D are amended and restated as follows: The information set forth in rows 11 and 13 of the cover pages to this Schedule 13D is incorporated by reference. The percentage set forth in row 13 is based on 1,919,441 outstanding shares of Common Stock, as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on November 12, 2025. In addition, Mr. Kam Chung Leung directly owns 8,684 shares of Common Stock.
(b)	The information set forth in rows 7 through 10 of the cover pages to this Schedule 13D is incorporated by reference.
(c)	Except as set forth on Schedule A, which is incorporated into this Item 5(c) by reference, no Reporting Person has effected any transaction in shares of Common Stock in the past sixty days.

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.

Nan Fung Group Holdings Limited

Signature:	/s/ Tang Chun Wai Nelson
Name/Title:	Tang Chun Wai Nelson, Director
Date:	02/17/2026

NF Investment Holdings Limited

Signature:	/s/ Tang Chun Wai Nelson
Name/Title:	Tang Chun Wai Nelson, Director
Date:	02/17/2026

Pivotal bioVenture Partners Fund I, L.P.

Signature:	By Pivotal bioVenture Partners Fund I G.P., L.P.
Name/Title:	its General Partner
Date:	02/17/2026

Signature:	By Pivotal bioVenture Partners Fund I U.G.P., Ltd.
Name/Title:	its General Partner
Date:	02/17/2026

Signature:	/s/ Robert Hopfner
Name/Title:	Robert Hopfner, Authorized Signatory
Date:	02/17/2026

Pivotal bioVenture Partners Fund I G.P., L.P.

Signature:	By Pivotal bioVenture Partners Fund I U.G.P., Ltd.
Name/Title:	its General Partner
Date:	02/17/2026

Signature:	/s/ Robert Hopfner
Name/Title:	Robert Hopfner, Authorized Signatory
Date:	02/17/2026

Pivotal bioVenture Partners Fund I U.G.P. Ltd.

Signature:	/s/ Robert Hopfner
Name/Title:	Robert Hopfner, Authorized Signatory
Date:	02/17/2026

Pivotal Partners Ltd

Signature:	/s/ Sun Xintong
Name/Title:	Sun Xintong, Director
Date:	02/17/2026

Pivotal Life Sciences Holdings Limited

Signature:	/s/ Sun Xintong
Name/Title:	Sun Xintong, Director
Date:	02/17/2026

Nan Fung Life Sciences Holdings Limited

Signature:	/s/ Sun Xintong
Name/Title:	Sun Xintong, Director
Date:	02/17/2026

Permwell Management Limited

Signature:	/s/ Tang Chun Wai Nelson
Name/Title:	Tang Chun Wai Nelson, Director
Date:	02/17/2026

NFLS Beta Limited

Signature:	/s/ Sun Xintong
Name/Title:	Sun Xintong, Director
Date:	02/17/2026

NFLS Platform Holdings Limited

Signature:	/s/ Sun Xintong
Name/Title:	Sun Xintong, Director
Date:	02/17/2026

FAQ

What ownership stake in Bolt Biotherapeutics (BOLT) does Nan Fung report?

Nan Fung Group Holdings Limited reports beneficial ownership of 128,119 shares of Bolt Biotherapeutics common stock, representing 6.7% of the class. This percentage is based on 1,919,441 shares outstanding, as disclosed in Bolt’s Form 10‑Q filed in November 2025.

How many Bolt Biotherapeutics (BOLT) shares do Pivotal bioVenture entities report?

Pivotal bioVenture Partners Fund I, L.P. and related entities report shared voting and dispositive power over 78,445 shares of Bolt Biotherapeutics common stock. This position represents 4.1% of the outstanding common stock, using the same 1,919,441-share baseline from Bolt’s November 2025 Form 10‑Q.

What is the total share count used to calculate ownership percentages for BOLT?

The ownership percentages in this amendment are calculated using 1,919,441 shares of Bolt Biotherapeutics common stock outstanding. This figure comes from the company’s Form 10‑Q filed on November 12, 2025, and serves as the baseline for all reported percentage stakes.

Does the Schedule 13D/A mention recent trading activity in BOLT shares?

The amendment states that, except as listed on Schedule A, no reporting person has effected any transaction in Bolt Biotherapeutics common stock during the past sixty days. This indicates limited recent trading activity by the reporting group over that period.

What personal ownership in BOLT is reported for Kam Chung Leung?

The filing notes that Mr. Kam Chung Leung directly owns 8,684 shares of Bolt Biotherapeutics common stock. This direct holding is separate from the larger positions reported by Nan Fung and Pivotal-related entities and is specifically identified in the interest in securities section.

Which jurisdictions are the main reporting entities for this BOLT Schedule 13D/A organized in?

The principal reporting entities are organized in the British Virgin Islands and the Cayman Islands. Nan Fung Group Holdings Limited and certain affiliates are based in the British Virgin Islands, while Pivotal bioVenture and several related holding companies are organized in the Cayman Islands.