[Form 4] Day One Biopharmaceuticals, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Day One Biopharmaceuticals (DAWN) CEO and director reported multiple internal transfers of common stock among family trusts on 11/25/2025. The Form 4 shows several code G transactions at a price of $0 per share, including transfers of 300,000 shares of common stock from the Bender Revocable Trust to the Jeremy Bender 2025 Grantor Retained Annuity Trust and to the Melissa Bender 2025 Grantor Retained Annuity Trust.

Additional movements involved 7,225 shares held by the Jeremy Bender 2022 Grantor Retained Annuity Trust, which decreased to zero after the reported transaction. Following these changes, the Bender Revocable Trust held 808,285 shares, while the various 2022 and 2023 Grantor Retained Annuity Trusts for Jeremy and Melissa Bender collectively held multiple indirect positions, including 177,165, 20,204, 147,702, and 18,197 shares of common stock. No derivative securities were reported.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Bender Jeremy

(Last) (First) (Middle)

1800 SIERRA POINT PARKWAY, SUITE 200

(Street)

BRISBANE CA 94005

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Day One Biopharmaceuticals, Inc. [ DAWN ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CHIEF EXECUTIVE OFFICER

3. Date of Earliest Transaction (Month/Day/Year)
11/25/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	11/25/2025		G		300,000	D	$0	1,108,285	I	By Bender Revocable Trust(1)
Common Stock	11/25/2025		G		300,000	A	$0	300,000	I	See footnote(2)
Common Stock	11/25/2025		G		300,000	D	$0	808,285	I	By Bender Revocable Trust(1)
Common Stock	11/25/2025		G		300,000	A	$0	300,000	I	See footnote(3)
Common Stock	11/25/2025		G		7,225	D	$0	7,225	I	See footnote(4)
Common Stock	11/25/2025		G		7,225	D	$0	0	I	See footnote(4)
Common Stock								177,165	D
Common Stock								20,204	I	See footnote(5)
Common Stock								147,702	I	See footnote(6)
Common Stock								18,197	I	See footnote(7)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents shares held by the Bender Revocable Trust dated January 18, 2017.

2. Represents shares held by the Jeremy Bender 2025 Grantor Retained Annuity Trust of which the Reporting Person is trustee.

3. Represents shares held by the Melissa Bender 2025 Grantor Retained Annuity Trust of which the Reporting Person's spouse is trustee.

4. Represents shares held by the Jeremy Bender 2022 Grantor Retained Annuity Trust of which the Reporting Person is trustee.

5. Represents shares held by The Jeremy Bender 2023 Grantor Retained Annuity Trust of which the Reporting Person is trustee.

6. Represents shares held by The Melissa Bender 2022 Grantor Retained Annuity Trust of which the Reporting Person's spouse is trustee.

7. Represents shares held by The Melissa Bender 2023 Grantor Retained Annuity Trust of which the Reporting Person's spouse is trustee.

	/s/ Charles N. York II, Attorney-in-Fact	11/26/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider activity did Day One Biopharmaceuticals (DAWN) report on this Form 4?

The Form 4 reports that the company’s chief executive officer and director engaged in several transfers of common stock on 11/25/2025, moving shares among the Bender Revocable Trust and multiple Grantor Retained Annuity Trusts for Jeremy and Melissa Bender at a per-share price of $0.

How many Day One (DAWN) shares were transferred between the Bender trusts?

The reported transactions include transfers of 300,000 shares of common stock from the Bender Revocable Trust to the Jeremy Bender 2025 Grantor Retained Annuity Trust and another 300,000 shares to the Melissa Bender 2025 Grantor Retained Annuity Trust, all at $0 per share.

What are the CEO’s indirect holdings in Day One Biopharmaceuticals after these transactions?

After the reported moves, the Bender Revocable Trust held 808,285 shares of common stock. Additional indirect holdings included 300,000 shares in the Jeremy Bender 2025 Grantor Retained Annuity Trust, 300,000 shares in the Melissa Bender 2025 Grantor Retained Annuity Trust, and stakes of 177,165, 20,204, 147,702, and 18,197 shares in various 2022 and 2023 Grantor Retained Annuity Trusts.

Were any derivative securities reported for Day One (DAWN) in this Form 4?

No derivative securities are listed in Table II. The filing focuses on non-derivative common stock positions and their transfers among the Bender family-related trusts.

What does the transaction code G indicate in the Day One (DAWN) Form 4?

The transactions in Table I use transaction code G and a price of $0 per share, indicating the reported moves are non-cash transfers of common stock among the Bender Revocable Trust and related Grantor Retained Annuity Trusts.

Who is the reporting person on this Day One Biopharmaceuticals Form 4?

The reporting person is the company’s chief executive officer and director, with shares held indirectly through the Bender Revocable Trust and several Grantor Retained Annuity Trusts for Jeremy and Melissa Bender, as described in the footnotes.