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).

1. Name and Address of Reporting Person* AI Day1 LLC (Last) (First) (Middle) C/O ACCESS INDUSTRIES, INC. 40 WEST 57TH STREET, 28TH FLOOR (Street) NEW YORK NY 10019 (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) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 01/18/2022
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X 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	01/18/2022		P		43,429	A	$14.2616(1)	9,421,205	D(2)
Common Stock	01/19/2022		P		58,818	A	$14.699(3)	9,480,023	D(2)
Common Stock	01/20/2022		P		4,615	A	$14.7293(4)	9,484,638	D(2)

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

1. Name and Address of Reporting Person* AI Day1 LLC (Last) (First) (Middle) C/O ACCESS INDUSTRIES, INC. 40 WEST 57TH STREET, 28TH FLOOR (Street) NEW YORK NY 10019 (City) (State) (Zip)

1. Name and Address of Reporting Person* Access Industries Holdings LLC (Last) (First) (Middle) C/O ACCESS INDUSTRIES, INC. 40 WEST 57TH STREET, 28TH FL (Street) NEW YORK NY 10019 (City) (State) (Zip)

1. Name and Address of Reporting Person* ACCESS INDUSTRIES MANAGEMENT, LLC (Last) (First) (Middle) C/O ACCESS INDUSTRIES, INC. 40 WEST 57TH STREET, 28TH FLOOR (Street) NEW YORK NY 10019 (City) (State) (Zip)

1. Name and Address of Reporting Person* Blavatnik Len (Last) (First) (Middle) C/O ACCESS INDUSTRIES, INC. 40 WEST 57TH STREET, 28TH FL (Street) NEW YORK NY 10019 (City) (State) (Zip)

Explanation of Responses:

1. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.05 to $14.53, inclusive. The reporting person undertakes to provide to Day One Biopharmaceuticals, Inc., any security holder of Day One Biopharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote to this Form 4.

2. The securities reported are held directly by AI Day 1 LLC and may be deemed to be beneficially owned by Access Industries Holdings LLC ("AIH"), Access Industries Management, LLC ("AIM") and Len Blavatnik because AIH indirectly controls all of the outstanding voting interests in AI Day 1 LLC, AIM controls AIH and Mr. Blavatnik controls AIM and holds a majority of the outstanding voting interests in AIH. AIH, AIM and Mr. Blavatnik each disclaims beneficial ownership of these securities, except to the extent of its or his pecuniary interest therein, and this form shall not be construed as an admission that any such reporting person is the beneficial owner of any of the securities reported on this form.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.16 to $14.75, inclusive. The reporting person undertakes to provide to Day One Biopharmaceuticals, Inc., any security holder of Day One Biopharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote to this Form 4.

4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.60 to $14.75, inclusive. The reporting person undertakes to provide to Day One Biopharmaceuticals, Inc., any security holder of Day One Biopharmaceuticals, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote to this Form 4.

Remarks:

	/s/ Alejandro Moreno for AI Day 1 LLC	01/20/2022
	/s/ Alejandro Moreno for Access Industries Holdings LLC	01/20/2022
	/s/ Alejandro Moreno for Access Industries Management, LLC	01/20/2022
	/s/ Alejandro Moreno as Attorney-in-Fact for Mr. Blavatnik	01/20/2022
	** Signature of Reporting Person	Date
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