SR One Capital Management Form 4 Arcellx / Simeon George ownership change

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

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X

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^*

SR ONE CAPITAL MANAGEMENT, LLC

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Arcellx, Inc. [ ACLX ]

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)
05/11/2023

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	05/11/2023		S		631,932	D	$45(1)	2,834,879	I	See Note 2(2)
Common Stock	05/11/2023		S		370,612	D	$45(1)	1,662,584	I	See Note 3(3)
Common Stock	05/11/2023		S		6,485	D	$46.15(4)	2,828,394	I	See Note 2(2)
Common Stock	05/11/2023		S		3,804	D	$46.15(4)	1,658,780	I	See Note 3(3)

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^*

SR ONE CAPITAL MANAGEMENT, LLC

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

SR One Capital Fund I Aggregator LP

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

SR ONE CAPITAL PARTNERS I, LP

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

George Simeon

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

SR One Co-Invest II, LLC

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

SR One Co-Invest II Manager, LLC

(Last) (First) (Middle)

985 OLD EAGLE SCHOOL ROAD

SUITE 511

(Street)

WAYNE PA 19087

(City) (State) (Zip)

Explanation of Responses:

1. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $45.00 to $45.745 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

2. The securities are directly held by SR One Capital Fund I Aggregator, LP ("SR One Fund I Aggregator"). SR One Capital Partners I, LP ("SR One Partners I") is the sole general partner of SR One Fund I Aggregator, and SR One Capital Management, LLC ("SR One Capital Management") is the sole general partner of SR One Partners I. Simeon George, M.D. is the managing member of SR One Capital Management (SR One Partners I, SR One Capital Management, and Dr. George together, the "Fund I Indirect Reporting Persons"). The Fund I Indirect Reporting Persons disclaim beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), or otherwise of such portion of the securities held by SR One Fund I Aggregator in which the Fund I Indirect Reporting Persons have no pecuniary interest.

3. The securities are directly held by SR One Co-Invest II, LLC ("SR One Co-Invest II"). SR One Co-Invest II Manager, LLC ("SR One Co-Invest II Manager") is the managing member of SR One Co-Invest II and SR One Capital Management is the managing member of SR One Co-Invest II Manager. Dr. George is the managing member of SR One Capital Management (SR One Co-Invest II Manager, SR One Capital Management, and Dr. George together, the "Co-Invest II Indirect Reporting Persons"). The Co-Invest II Indirect Reporting Persons disclaim beneficial ownership within the meaning of Section 16 or otherwise of such portion of the securities held by SR One Co-Invest II in which the Co-Invest II Indirect Reporting Persons have no pecuniary interest.

4. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $46.00 to $46.56 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Remarks:

	/s/ Sasha Keough, attorney-in-fact for SR One Capital Management, LLC	05/15/2023
	/s/ Sasha Keough, attorney-in-fact for SR One Capital Fund I Aggregator, LP	05/15/2023
	/s/ Sasha Keough, attorney-in-fact for SR One Capital Partners I, LP	05/15/2023
	/s/ Sasha Keough, attorney-in-fact for Simeon George	05/15/2023
	/s/ Sasha Keough, attorney-in-fact for SR One Co-Invest II, LLC	05/15/2023
	/s/ Sasha Keough, attorney-in-fact for SR One Co-Invest II Manager, LLC	05/15/2023
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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