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* BB BIOVENTURES L P (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Pharmasset Inc [ VRUS ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner
	3. Date of Earliest Transaction (Month/Day/Year) 06/19/2008
	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	06/19/2008		S		153,700(1)	D	$19.9	2,120,431	I	See Footnote(2)
Common Stock	06/19/2008		S		500(3)	D	$19.91	2,119,931	I	See Footnote(4)
Common Stock	06/19/2008		S		100(5)	D	$19.92	2,119,831	I	See Footnote(6)
Common Stock	06/19/2008		S		100(7)	D	$19.94	2,119,731	I	See Footnote(8)
Common Stock	06/19/2008		S		1,400(9)	D	$20	2,118,331	I	See Footnote(10)

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* BB BIOVENTURES L P (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* BAB BIO VENTURES LLP (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* BAB BIO VENTURES NV (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* MPM ASSET MANAGEMENT INVESTORS 1999 LLC (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* MPM BIOVENTURES PARALLEL FUND L P (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* MPM BIOVENTURES I LP (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* MPM BIO VENTURES I LLC (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* STEINMETZ MICHAEL (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

1. Name and Address of Reporting Person* GADICKE ANSBERT (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner

Explanation of Responses:

1. These shares were sold as follows: 68,391 shares by BB BioVentures, L.P. ("BBBV"), 9,220 shares by MPM BioVentures Parallel Fund, L.P. ("BV PF"), 815 shares by MPM Asset Management Investors 1999 LLC ("AM 1999"), 3,971 shares by MPM BioVentures III, L.P., ("BV III"), 59,073 shares by MPM BioVentures III-QP, L.P. ("BV III QP"), 4,993 shares held by MPM BioVentures III GmbH & Co. Beteiligungs KG ("BV KG"), 1,785 shares by MPM BioVentures III Parallel Fund, L.P. ("BV III PF"), 1,403 shares held by MPM Asset Management Investors 2004 BVIII LLC ("AM BV III"), 3,949 by MPM BioVentures III GP, LP ("BV III GP") and 100 by MPM Capital, L.P. ("MPM LP"). MPM BioVentures I, L.P. ("BV I") and MPM BioVentures I LLC ("BV I LLC") are the direct and indirect general partners of BV PF. BAB BioVentures L.P. ("BAB BV"), BAB BioVentures, N.V. ("BAB NV") and BV I LLC are the direct and indirect general partners of BBBV. Michael Steinmetz and Ansbert Gadicke are managers of AM 1999 and BV I LLC. BV III GP and MPM BioVentures III LLC ("BV III LLC") are the direct and indirect general partners of BV III, BV III QP, BV III PF and BV KG. Michael Steinmetz and Ansbert Gadicke are Series A members of BV III LLC and managers of AM BV III. Ansbert Gadicke has a controlling interest in MPM LP. Each Reporting Person disclaims beneficial ownership of all such shares except to the extent of their respective proportionate pecuniary interests therein.

2. The shares are held as follows: 943,507 by BBBV, 127,194 by BV PF, 11,251 by AM 1999, 54,801 by BV III, 814,953 by BV III QP, 68,868 by BV KG, 24,612 by BV III PF, 19,374 by AM BV III, 54,502 by BV III GP and 1,369 by MPM LP. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of their respective proportionate pecuniary interest therein.

3. The shares were sold as follows: 222 by BBBV, 30 by BV PF, 3 by AM 1999, 13 by BV III, 192 by BV III QP, 16 by BV KG, 6 by BV III PF, 5 by AM BV III and 13 by BV III GP.

4. The shares are held as follows: 943,285 by BBBV, 127,164 by BV PF, 11,248 by AM 1999, 54,788 by BV III, 814,761 by BV III QP, 68,852 by BV KG, 24,606 by BV III PF, 19,369 by AM BV III, 54,489 by BV III GP and 1,369 by MPM LP. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of their respective proportionate pecuniary interest therein.

5. The shares were sold as follows: 44 by BBBV, 6 by BV PF, 1 by AM 1999, 3 by BV III, 38 by BV III QP, 3 by BV KG, 1 by BV III PF, 1 by AM BV III and 3 by BV III GP.

6. The shares are held as follows: 943,241 by BBBV, 127,158 by BV PF, 11,247 by AM 1999, 54,785 by BV III, 814,723 by BV III QP, 68,849 by BV KG, 24,605 by BV III PF, 19,368 by AM BV III, 54,486 by BV III GP and 1,369 by MPM LP. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of their respective proportionate pecuniary interest therein.

7. The shares were sold as follows: 44 by BBBV, 6 by BV PF, 1 by AM 1999, 3 by BV III, 38 by BV III QP, 3 by BV KG, 1 by BV III PF, 1 by AM BV III and 3 by BV III GP.

8. The shares are held as follows: 943,197 by BBBV, 127,152 by BV PF, 11,246 by AM 1999, 54,782 by BV III, 814,685 by BV III QP, 68,846 by BV KG, 24,604 by BV III PF, 19,367 by AM BV III, 54,483 by BV III GP and 1,369 by MPM LP. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of their respective proportionate pecuniary interest therein.

9. The shares were sold as follows: 624 by BBBV, 84 by BV PF, 7 by AM 1999, 36 by BV III, 538 by BV III QP, 45 by BV KG, 16 by BV III PF, 13 by AM BV III, 36 by BV III GP and 1 by MPM LP.

10. The shares are held as follows: 942,573 by BBBV, 127,068 by BV PF, 11,239 by AM 1999, 54,746 by BV III, 814,147 by BV III QP, 68,801 by BV KG, 24,588 by BV III PF, 19,354 by AM BV III, 54,447 by BV III GP and 1,368 by MPM LP. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of their respective proportionate pecuniary interest therein.

	By Ansbert Gadicke, managing director of BAB BioVentures NV, the general partner of BAB BioVentures L.P., the general partner of BB BioVentures L.P. /s/ Ansbert Gadicke	06/23/2008
	By Ansbert Gadicke, managing director of BAB BioVentures NV, the general partner of BAB BioVentures L.P. /s/ Ansbert Gadicke	06/23/2008
	By Ansbert Gadicke, managing director of BAB BioVentures NV /s/ Ansbert Gadicke	06/23/2008
	By Luke Evnin, manager of MPM Asset Management Investors 1999 LLC /s/ Luke Evnin	06/23/2008
	By Luke Evnin, manager of MPM BioVentures I LLC, the general partner of MPM BioVentures I L.P., the general partner of MPM BioVentures Parallel Fund, L.P. /s/ Luke Evnin	06/23/2008
	By Luke Evnin, manager of MPM BioVentures I LLC, the general partner of MPM BioVentures I L.P. /s/ Luke Evnin	06/23/2008
	By Luke Evnin, manager of MPM BioVentures I LLC /s/ Luke Evnin	06/23/2008
	/s/ Michael Steinmetz	06/23/2008
	/s/ Ansbert Gadicke	06/23/2008
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.