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* Charles River Partnership XIII, LP (Last) (First) (Middle) 1000 WINTER STREET SUITE 3300 (Street) WALTHAM MA 02451 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol RPX Corp [ RPXC ]	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) 05/04/2011
	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	05/04/2011		C		8,597,979(1)	A	(2)(3)(4)(5)	8,597,979(1)	D(1)

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
Series A Preferred Stock	(2)	05/04/2011		C			3,448,276(7)	(2)	(2)	Common Stock	3,448,276(2)(7)	$0	0	D(6)
Series A-1 Preferred Stock	(3)	05/04/2011		C			3,466,445(8)	(3)	(3)	Common Stock	3,466,445(3)(8)	$0	0	D(6)
Series B Preferred Stock	(4)	05/04/2011		C			1,574,003(9)	(4)	(4)	Common Stock	1,574,003(4)(9)	$0	0	D(6)
Series C Preferred Stock	(5)	05/04/2011		C			109,255(10)	(5)	(5)	Common Stock	109,255(5)(10)	$0	0	D(6)

1. Name and Address of Reporting Person* Charles River Partnership XIII, LP (Last) (First) (Middle) 1000 WINTER STREET SUITE 3300 (Street) WALTHAM MA 02451 (City) (State) (Zip)

1. Name and Address of Reporting Person* Charles River Friends XIII-A LP (Last) (First) (Middle) c/o Charles River Ventures Inc 1000 Winter Street, Suite 3300 (Street) Waltham MA 02451 (City) (State) (Zip)

1. Name and Address of Reporting Person* Charles River XIII GP, LP (Last) (First) (Middle) 1000 WINTER STREET SUITE 3300 (Street) WALTHAM MA 02451 (City) (State) (Zip)

1. Name and Address of Reporting Person* Charles River XIII GP, LLC (Last) (First) (Middle) 1000 WINTER STREET SUITE 3300 (Street) WALTHAM MA 02451 (City) (State) (Zip)

Explanation of Responses:

1. Represents shares received upon conversion of shares of Series A, Series A-1, Series B, and Series C convertible preferred stock (as described in Notes 2 through 5) as follows: 8,363,239 shares held by Charles River Partnership XIII, LP ("CRP XIII") and 234,740 shares held by Charles River Friends XIII-A, LP ("CRF XIII-A"). CRP XIII and CRF XIII-A form a "group" for purposes of Section 13(d) of the Securities Exchange Act of 1934.

2. Effective upon the issuer's sale of its common stock in its initial public offering, each share of Series A convertible preferred stock automatically converted into 1 share of common stock. The Series A convertible preferred stock had no expiration date.

3. Effective upon the issuer's sale of its common stock in its initial public offering, each share of Series A-1 convertible preferred stock automatically converted into 1 share of common stock. The Series A-1 convertible preferred stock had no expiration date.

4. Effective upon the issuer's sale of its common stock in its initial public offering, each share of Series B convertible preferred stock automatically converted into 1 share of common stock. The Series B convertible preferred stock had no expiration date.

5. Effective upon the issuer's sale of its common stock in its initial public offering, each share of Series C convertible preferred stock automatically converted into 1 share of common stock. The Series C convertible preferred stock had no expiration date.

6. Charles River XIII GP, LP ("CR XIII GP, LP") is the General Partner of CRP XIII. Charles River XIII GP, LLC ("CR XIII GP LLC") is the General Partner of both CRF XIII-A and Charles River XIII GP, LP. Each of CR XIII GP, LP and CR XIII GP LLC may be deemed to beneficially own the reported securities, but each disclaims beneficial ownership of such reported securities except to the extent of its pecuniary interest therein. The filing of this statement by any reporting person shall not be deemed an admission that such person is, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the beneficial owner of any equity securities covered by this statement.

7. Represents 3,354,132 shares held by CRP XIII and 94,144 shares held by CRF XIII-A.

8. Represents 3,371,805 shares held by CRP XIII and 94,640 shares held by CRF XIII-A.

9. Represents 1,531,030 shares held by CRP XIII and 42,973 shares held by CRF XIII-A.

10. Represents 106,272 shares held by CRP XIII and 2,983 shares held by CRF XIII-A.

	Sarah Reed as Attorney-in-Fact for Charles River Partnership XIII, LP	05/05/2011
	Sarah Reed as Attorney-in-Fact for Charles River Friends XIII-A, LP	05/05/2011
	Sarah Reed as Attorney-in-Fact for Charles River XIII GP, LP	05/05/2011
	Sarah Reed as Attorney-in-Fact for Charles River XIII GP, LLC	05/05/2011
	** 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).
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