SCHEDULE 13D/A

BOLT BIOTHERAPEUTICS INC

Common Stock, $0.00001 par value · CUSIP: 097702203

Event date: 2026-02-05

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• Nan Fung Group Holdings LimitedReported CIK 0001782539

  Shares: 128,119 · Class: 6.7%

• NF Investment Holdings Limited

  Shares: 128,119 · Class: 6.7%

• Pivotal bioVenture Partners Fund I, L.P.Reported CIK 0001695076

  Shares: 78,445 · Class: 4.1%

• Pivotal bioVenture Partners Fund I G.P., L.P.Reported CIK 0001752862

  Shares: 78,445 · Class: 4.1%

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

  Shares: 78,445 · Class: 4.1%

• Pivotal Partners Ltd

  Shares: 78,445 · Class: 4.1%

• Pivotal Life Sciences Holdings Limited

  Shares: 78,445 · Class: 4.1%

• Nan Fung Life Sciences Holdings Limited

  Shares: 123,119 · Class: 6.4%

• Permwell Management Limited

  Shares: 5,000 · Class: 0.3%

• NFLS Beta Limited

  Shares: 44,674 · Class: 2.3%

• NFLS Platform Holdings Limited

  Shares: 44,674 · Class: 2.3%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.