DYNAVAX TECHNOLOGIES CORP — Director's Dealing 2025

Dec 29, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: DYNAVAX TECHNOLOGIES CORP (DVAX)
CIK: 0001029142
Period of Report: 2025-12-23

Reporting Person: MacDonald Kelly (SVP and CFO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-12-23	Common Stock	A	37500	—	Acquired	66727	Direct
2025-12-23	Common Stock	M	15477	—	Acquired	82204	Direct
2025-12-23	Common Stock	M	14141	—	Acquired	96345	Direct
2025-12-24	Common Stock	F	36141	$15.38	Disposed	60204	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-12-23	Restricted Stock Unit	$	M	15477	Disposed		Common Stock (15477)	Direct
2025-12-23	Restricted Stock Unit	$	M	14141	Disposed		Common Stock (14141)	Direct

Footnotes

F1: On December 23, 2025 (the "Effective Date"), in connection with the execution of an Agreement and Plan of Merger dated as of the Effective Date (the "Merger Agreement") by and among the Issuer, SANOFI, a French societe anonyme ("Parent"), and Samba Merger
Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Parent, the Board of Directors of the Issuer approved acceleration of vesting of certain performance-based restricted stock units ("PSUs") and restricted stock units ("RSUs") previously granted to the
Reporting Person, effective as of the Effective Date.

F2: Represents PSUs previously granted to the Reporting Person that vest based on how the Issuer's total stockholder return compares to the total stockholder return of an indexed group of companies ("rTSR") over a performance period ending on December 31, 2025. Each
PSU represents a contingent right to receive one share of common stock. On the Effective Date, the Board of Directors of the Issuer determined that these PSUs (which represent 125% of the target number of PSUs) were earned according to achievement of the rTSR
performance condition over a shortened performance period, with the Issuer's total stockholder return determined based on the amount payable for a share of the Issuer's common stock pursuant to the Merger Agreement ($15.50), and approved such acceleration of vesting
of the earned PSUs.

F3: Each RSU represents a contingent right to receive one share of the Issuer's common stock.

F4: Shares withheld by the Issuer to satisfy tax withholding requirements on vesting of PSUs and RSUs.

F5: The RSUs were granted on February 15, 2024, and were originally scheduled to vest over three years, with 1/3 vesting on each anniversary of February 15, 2024.

F6: The RSUs were granted on February 13, 2025, and were originally scheduled to vest over three years, with 1/3 vesting on each anniversary of February 13, 2025.