BRIAN O'CALLAGHAN - 12 Dec 2025 Form 4 Insider Report for Bolt Biotherapeutics, Inc. (BOLT)

Role
Director
Signature
/s/ William P. Quinn, Attorney-in-Fact
Issuer symbol
BOLT
Transactions as of
12 Dec 2025
Net transactions value
$0
Form type
4
Filing time
16 Dec 2025, 17:13:12 UTC
Previous filing
02 Jul 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
O'CALLAGHAN BRIAN Director C/O BOLT BIOTHERAPEUTICS, INC., 900 CHESAPEAKE DRIVE, REDWOOD CITY /s/ William P. Quinn, Attorney-in-Fact 16 Dec 2025 0001415015

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction BOLT Director Stock Option (Right to Buy) Award +1,393 1,393 12 Dec 2025 Common Stock 1,393 $5.44 Direct F1, F2
transaction BOLT Director Stock Option (Right to Buy) Disposed to Issuer -1,393 -100% 0 12 Dec 2025 Common Stock 1,393 $180.20 Direct F1, F2
transaction BOLT Director Stock Option (Right to Buy) Award +1,810 1,810 12 Dec 2025 Common Stock 1,810 $5.44 Direct F1, F3
transaction BOLT Director Stock Option (Right to Buy) Disposed to Issuer -1,810 -100% 0 12 Dec 2025 Common Stock 1,810 $60.60 Direct F1, F3
transaction BOLT Director Stock Option (Right to Buy) Award +1,250 1,250 12 Dec 2025 Common Stock 1,250 $5.44 Direct F1, F4
transaction BOLT Director Stock Option (Right to Buy) Disposed to Issuer -1,250 -100% 0 12 Dec 2025 Common Stock 1,250 $39.80 Direct F1, F4
transaction BOLT Director Stock Option (Right to Buy) Award +1,250 1,250 12 Dec 2025 Common Stock 1,250 $5.44 Direct F1, F5
transaction BOLT Director Stock Option (Right to Buy) Disposed to Issuer -1,250 -100% 0 12 Dec 2025 Common Stock 1,250 $32.60 Direct F1, F5
transaction BOLT Director Stock Option (Right to Buy) Award +1,100 1,100 12 Dec 2025 Common Stock 1,100 $5.44 Direct F1, F6
transaction BOLT Director Stock Option (Right to Buy) Disposed to Issuer -1,100 -100% 0 12 Dec 2025 Common Stock 1,100 $15.36 Direct F1, F6
transaction BOLT Director Stock Option (Right to Buy) Award +1,100 1,100 12 Dec 2025 Common Stock 1,100 $5.44 Direct F7, F8
transaction BOLT Director Stock Option (Right to Buy) Disposed to Issuer -1,100 -100% 0 12 Dec 2025 Common Stock 1,100 $6.40 Direct F7, F8
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 The option is fully vested and exercisable.
F2 The reporting person agreed to cancellation of an option granted on November 17, 2021, in exchange for a new option having a lower exercise price.
F3 The reporting person agreed to cancellation of an option granted on March 24, 2022, in exchange for a new option having a lower exercise price.
F4 The reporting person agreed to cancellation of an option granted on June 10, 2022, in exchange for a new option having a lower exercise price.
F5 The reporting person agreed to cancellation of an option granted on June 12, 2023, in exchange for a new option having a lower exercise price.
F6 The reporting person agreed to cancellation of an option granted on June 12, 2024, in exchange for a new option having a lower exercise price.
F7 The shares subject to the option will vest on the earlier of May 27, 2026 or the day immediately prior to the next annual meeting of stockholders, subject to the Reporting Person's continuous service through such date; provided, however that the option will vest in full upon a change in control of the Issuer.
F8 The reporting person agreed to cancellation of an option granted on May 27, 2025, in exchange for a new option having a lower exercise price.