William P. Quinn - 16 Sep 2026 Form 4 Insider Report for Bolt Biotherapeutics, Inc. (BOLT)

Reporting relationship: President, CEO and CFO, Director
Issuer ticker: BOLT
Reported as of: 16 Sep 2026
Net transaction value: -$55,933
SEC form: 4
Accepted by SEC: 21 Sep 2026, 18:03:56 UTC
Prior SEC filing: 04 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ William P. Quinn

Filing notes and source

Key filing fact

William P. Quinn filed Form 4 for Bolt Biotherapeutics, Inc. (BOLT) on 21 Sep 2026.

Key facts

This page summarizes William P. Quinn's Form 4 filing for Bolt Biotherapeutics, Inc. (BOLT).
4 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 21 Sep 2026, 18:03.

Change

Previous filing in this sequence was filed on 04 Feb 2026.
Current net transaction value: -$55,933.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001724190 Primary reporting owner

Quinn William P.

Relationship: President, CEO and CFO, Director
Address: C/O BOLT BIOTHERAPEUTICS, INC., 900 CHESAPEAKE DRIVE, REDWOOD CITY
Signature: /s/ William P. Quinn
Signature date: 21 Sep 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

BOLT transaction

Common Stock

Purchase

Transaction value: $2,469
Shares: +637
Change %: +28%
Price: $3.88
Shares after: 2,950
Date: 05 Jun 2026
Ownership: Direct
Footnotes: F1

BOLT transaction

Common Stock

Sale

Transaction value: -$7,129
Shares: -1,889
Change %: -4.4%
Price: $3.77
Shares after: 41,061
Date: 16 Sep 2026
Ownership: Direct
Footnotes: F2

BOLT transaction

Common Stock

Sale

Transaction value: -$21,718
Shares: -6,545
Change %: -16%
Price: $3.32
Shares after: 34,516
Date: 17 Sep 2026
Ownership: Direct
Footnotes: F3

BOLT transaction

Common Stock

Sale

Transaction value: -$29,555
Shares: -9,132
Change %: -26%
Price: $3.24
Shares after: 25,384
Date: 18 Sep 2026
Ownership: Direct
Footnotes: F4

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 4 footnotes

Footnote F1

These shares were acquired under the Issuer's Employee Stock Purchase Plan in transactions that were exempt under Rule 16b-3(c).

Footnote F2

Represents weighted average sales price. These shares were sold by the reporting person to cover tax withholding obligations in connection with the vesting of the restricted stock units granted on October 22, 2025. The shares were sold at prices ranging from $3.60 to $4.14. The Reporting Person will provide upon request, to the Securities and Exchange Commission (the "SEC"), the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price.

Footnote F3

Represents weighted average sales price. These shares were sold by the reporting person to cover tax withholding obligations in connection with the vesting of the restricted stock units granted on October 22, 2025. The shares were sold at prices ranging from $3.22 to $3.67. The Reporting Person will provide upon request, to the Securities and Exchange Commission (the "SEC"), the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price.

Footnote F4

Represents weighted average sales price. These shares were sold by the reporting person to cover tax withholding obligations in connection with the vesting of the restricted stock units granted on October 22, 2025. The shares were sold at prices ranging from $3.15 to $3.41. The Reporting Person will provide upon request, to the Securities and Exchange Commission (the "SEC"), the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price.