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* Hadley Harbor Master Investors (Cayman) II L.P. (Last) (First) (Middle) C/O WELLINGTON MANAGEMENT COMPANY LLP 280 CONGRESS STREET (Street) BOSTON MA 02210 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 03/14/2018	3. Issuer Name and Ticker or Trading Symbol Arcus Biosciences, Inc. [ RCUS ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 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)

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
Series C Convertible Preferred Stock	(1)	(1)	Common Stock	1,496,813	(1)	D

Explanation of Responses:

1. Each share of Series C Convertible Preferred Stock is convertible into shares of common stock on a 1-for-1 basis at the option of the reporting person or upon the occurrence of certain events and has no expiration date. The Series C Convertible Preferred Stock reported in the table above reflects a 3.96-for-1 reverse stock split that was effected in connection with the Issuer's initial public offering.

Remarks:

	Hadley Harbor Master Investors (Cayman) II L.P., By: Wellington Alternative Investments, as General Partner, /s/ Matthew Shea, Title: Authorized Person	03/14/2018
	** 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).
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