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
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* Arch Venture Fund VII LP (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Receptos, Inc. [ RCPT ]	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) 05/13/2014
	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	05/13/2014		S		616	D	$28.72(1)	129,139	D(4)(6)
Common Stock	05/13/2014		S		1,535	D	$30.44(2)	127,604	D(4)(6)
Common Stock	05/14/2014		S		488	D	$28.39(3)	127,116	D(4)(6)
Common Stock	05/13/2014		S		10,013	D	$28.72(1)	2,091,363	D(5)(6)
Common Stock	05/13/2014		S		24,822	D	$30.44(2)	2,066,541	D(5)(6)
Common Stock	05/14/2014		S		7,907	D	$28.39(3)	2,058,634	D(5)(6)

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* Arch Venture Fund VII LP (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH Venture Partners VII, L.P. (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH Venture Partners VII, LLC (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH VENTURE FUND VI LP (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH VENTURE PARTNERS VI LP (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ARCH VENTURE PARTNERS VI LLC (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* CRANDELL KEITH (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BYBEE CLINTON (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* NELSEN ROBERT (Last) (First) (Middle) 8725 WEST HIGGINS ROAD, SUITE 290 (Street) CHICAGO IL 60631 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

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 $28.60 to $29.60, inclusive. The reporting person takes to provide to RCPT, any security holder of RCPT, 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 footnotes (1), (2), and (3) to this Form 4.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $30.00 to $31.00, inclusive.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $28.00 to $29.00, inclusive.

4. Beneficial ownership consists of an aggregate of 127,116 shares of common stock held by ARCH Venture Fund VI, L.P. ("ARCH Fund VI"). The sole general partner of ARCH Fund VI is ARCH Venture Partners VI, L.P. ("ARCH Partners VI"), which may be deemed to beneficially own the shares held by ARCH Fund VI. The sole general partner of ARCH Partners VI is ARCH Venture Partners VI, LLC ("ARCH VI LLC"), which may be deemed to beneficially own the shares held by ARCH Fund VI. ARCH Partners VI and ARCH VI LLC disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

5. Beneficial ownership consists of 2,058,634 shares of common stock held by ARCH Venture Fund VII, L.P. ("ARCH Fund VII"). The sole general partner of ARCH Fund VII is ARCH Venture Partners VII, L.P. ("ARCH Partners VII"), which may be deemed to be the beneficial owner of the shares held by ARCH Fund VII. The sole general partner of ARCH Partners VII is ARCH Venture Partners VII, LLC ("ARCH VII LLC"), which may be deemed to be the beneficial owner of the shares held by ARCH Fund VII. ARCH Partners VII and ARCH VII LLC disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

6. The managing directors of ARCH VI LLC and ARCH VII LLC are Keith Crandell, Clinton Bybee and Robert Nelsen, and they may be deemed to beneficially own the shares held by ARCH Fund VI and ARCH Fund VII. Messrs. Crandell, Bybee and Nelsen disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

Remarks:

	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell, Managing Director of the general partner of the general partner of ARCH Fund VII	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell, Managing Director of the general partner of ARCH Partners VII	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell, Managing Director of ARCH VII LLC	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell, Managing Director of the general partner of the general partner of ARCH Fund VI	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell, Managing Director of the general partner of ARCH Partners VI	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell, Managing Director of ARCH VI LLC	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Keith Crandell	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Clinton Bybee	05/15/2014
	/s/ Mark McDonnell - as Attorney-in-Fact for Robert Nelsen	05/15/2014
	** 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).
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