Holles Natalie C. Form 3 Day One Biopharmaceuticals / Natalie C. Holles ownership change

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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

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1. Name and Address of Reporting Person^*

Holles Natalie C.

(Last) (First) (Middle)

395 OYSTER POINT BLVD, SUITE 217

(Street)

SOUTH SAN FRANCISCO CA 94080

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
05/26/2021

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

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

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

5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	57,310(1)	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (right to buy Common Stock)	(2)	05/22/2031	Common Stock	40,000	16	D
Stock Option (right to buy Common Stock)	(3)	05/22/2031	Common Stock	40,300	16	D

Explanation of Responses:

1. Certain of the shares are subject to the Issuer's right of repurchase if underlying vesting conditions are not met.

2. The option vests as to 1/36th of the total shares on each monthly anniversary, beginning on June 23, 2021, subject to the Reporting Person's provision of service to the Issuer on each vesting date.

3. The option vests as to 1/48th of the total shares on each monthly anniversary, beginning on March 25, 2021, subject to the Reporting Person's provision of service to the Issuer on each vesting date.

Remarks:

	/s/ Charles N. York II, as Attorney-in-Fact	05/26/2021
	** 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 5 (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.
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