John L. Slebir - 23 Dec 2025 Form 4 Insider Report for DYNAVAX TECHNOLOGIES CORP (DVAX)

Reporting relationship: SVP General Counsel
Issuer ticker: DVAX
Reported as of: 23 Dec 2025
Net transaction value: -$499,881
SEC form: 4
Accepted by SEC: 29 Dec 2025, 16:08:06 UTC
Prior SEC filing: 21 Feb 2025
Next SEC filing: 10 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ John L. Slebir

Key filing fact

John L. Slebir filed Form 4 for DYNAVAX TECHNOLOGIES CORP (DVAX) on 29 Dec 2025.

Key facts

This page summarizes John L. Slebir's Form 4 filing for DYNAVAX TECHNOLOGIES CORP (DVAX).
6 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 29 Dec 2025, 16:08.

Change

Previous filing in this sequence was filed on 21 Feb 2025.
Current net transaction value: -$499,881.

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 0001475990 Primary reporting owner

Slebir John L

Relationship: SVP General Counsel
Address: C/O DYNAVAX TECHNOLOGIES, 2100 POWELL STREET, SUITE 720, EMERYVILLE
Signature: /s/ John L. Slebir
Signature date: 29 Dec 2025

Reported non-derivative transactions

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

DVAX transaction

Common Stock

Award

Transaction value
Shares: +33,750
Change %: +90%
Price
Shares after: 71,328
Date: 23 Dec 2025
Ownership: Direct
Footnotes: F1, F2, F3

DVAX transaction

Common Stock

Options Exercise

Transaction value
Shares: +16,667
Change %: +23%
Price
Shares after: 87,995
Date: 23 Dec 2025
Ownership: Direct
Footnotes: F1, F3, F4

DVAX transaction

Common Stock

Options Exercise

Transaction value
Shares: +14,141
Change %: +16%
Price
Shares after: 102,136
Date: 23 Dec 2025
Ownership: Direct
Footnotes: F1, F3, F4

DVAX transaction

Common Stock

Tax liability

Transaction value: $499,881
Shares: -32,502
Change %: -32%
Price: $15.38
Shares after: 69,634
Date: 24 Dec 2025
Ownership: Direct
Footnotes: F3, F5

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

DVAX transaction Derivative

Restricted Stock Unit

Options Exercise

Transaction value
Shares: -16,667
Change %: -50%
Price
Shares after: 16,667
Date: 23 Dec 2025
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 16,667
Exercise price
Footnotes: F1, F4, F6

DVAX transaction Derivative

Restricted Stock Unit

Options Exercise

Transaction value
Shares: -14,141
Change %: -33%
Price
Shares after: 28,282
Date: 23 Dec 2025
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 14,141
Exercise price
Footnotes: F1, F4, F7

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 7 footnotes

Footnote 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.

Footnote 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.

Footnote F3

Includes 1,205 shares purchased through the Issuer's Employee Stock Purchase Plan on August 15, 2025.

Footnote F4

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

Footnote F5

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

Footnote F6

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.

Footnote F7

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.