Habib J. Dable - 23 Apr 2026 Form 4 Insider Report for Day One Biopharmaceuticals, Inc. (DAWN)

Reporting relationship: Director
Issuer ticker: DAWN
Reported as of: 23 Apr 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 23 Apr 2026, 16:33:16 UTC
Prior SEC filing: 20 Apr 2026
Next SEC filing: 10 Jun 2026
Source filing: View source filing
Reporting owner signature: /s/ Charles N. York II, as Attorney-in-Fact

Key filing fact

Habib J. Dable filed Form 4 for Day One Biopharmaceuticals, Inc. (DAWN) on 23 Apr 2026.

Key facts

This page summarizes Habib J. Dable's Form 4 filing for Day One Biopharmaceuticals, Inc. (DAWN).
4 reported transactions and 4 derivative rows are listed below.
Accepted by SEC: 23 Apr 2026, 16:33.

Change

Previous filing in this sequence was filed on 20 Apr 2026.
Current net transaction value: $0.

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 0001690773 Primary reporting owner

Dable Habib J

Relationship: Director
Address: 1800 SIERRA POINT PARKWAY, SUITE 200, BRISBANE
Signature: /s/ Charles N. York II, as Attorney-in-Fact
Signature date: 23 Apr 2026

Reported derivative securities

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

DAWN transaction Derivative

Stock Option (right to buy Common Stock)

Disposed to Issuer

Transaction value
Shares: -66,660
Change %: -100%
Price
Shares after: 0
Date: 23 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 66,660
Exercise price: $8.99
Footnotes: F1, F2, F3, F4

DAWN transaction Derivative

Stock Option (right to buy Common Stock)

Disposed to Issuer

Transaction value
Shares: -32,335
Change %: -100%
Price
Shares after: 0
Date: 23 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 32,335
Exercise price: $8.99
Footnotes: F2, F3, F4, F5

DAWN transaction Derivative

Stock Option (right to buy Common Stock)

Disposed to Issuer

Transaction value
Shares: -22,500
Change %: -100%
Price
Shares after: 0
Date: 23 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 22,500
Exercise price: $7.01
Footnotes: F2, F3, F4, F6

DAWN transaction Derivative

Restricted Stock Unit (RSU)

Disposed to Issuer

Transaction value
Shares: -15,000
Change %: -100%
Price
Shares after: 0
Date: 23 Apr 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 15,000
Exercise price
Footnotes: F2, F3, F4, F7, F8, F9

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

Additional SEC filing notes

Filing notes and footnotes

Section 16 status

Habib J. Dable is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may still apply in specific circumstances.

Explanation of responses 9 footnotes

Footnote F1

The option vests as to 1/36th of the total shares on each monthly anniversary, beginning on February 17, 2024, subject to the Reporting Person's provision of service to the Issuer on each vesting date.

Footnote F2

On March 6, 2026, Servier Pharmaceuticals LLC, a Delaware limited liability company ("Parent"), Servier Detroit Inc., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"), Day One Biopharmaceuticals, Inc., a Delaware corporation (the "Company"), and Servier S.A.S., a French societe par actions simplifiee, solely as a guarantor, entered into an Agreement and Plan of Merger (the "Merger Agreement"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Company (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Company surviving the Merger as a wholly owned subsidiary of the Parent.

Footnote F3

Upon the closing of the Merger on April 23, 2026, each issued and outstanding share of the Company's Common Stock, par value $0.0001 per share, was either (x) purchased for $21.50 per share (the "Offer Price"), net to the seller in cash, without interest, and subject to applicable withholding taxes, on the terms and conditions set forth in the Merger Agreement, or (y) automatically converted into the right to receive the Offer Price (the "Merger Consideration"), net to the seller in cash, without interest, and subject to applicable withholding taxes, on the terms and conditions set forth in the Merger Agreement.

Footnote F4

Immediately prior to the effective time of the Merger, all outstanding unvested stock options and unvested restricted stock units became fully vested. At the effective time of the Merger, each stock option and restricted stock unit was canceled and converted into the right to receive an amount in cash equal to the Merger Consideration (or, in the case of stock options, the difference between the Merger Consideration and the applicable per share exercise price), less any applicable withholding taxes.

Footnote F5

The options are fully vested.

Footnote F6

The option vests as to 1/12th of the total grant on each monthly anniversary, beginning on July 2, 2025, subject to the Reporting Person's provision of service to the Issuer on each option vesting date.

Footnote F7

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the Issuer's Common Stock upon settlement for no consideration.

Footnote F8

The RSUs will vest as to 100% of the award on the earlier of (i) June 2, 2026 and (ii) the date of the Issuer's 2026 annual meeting of stockholders (in each case, the "RSU Vesting Date"), subject to the Reporting Person's provision of services to the Issuer on each RSU Vesting Date. Shares of the Issuer's Common Stock will be delivered to the Reporting Person following vesting.

Footnote F9

RSUs do not expire; they either vest or are canceled prior to the RSU Vesting Date.