13G Filing: Partner Fund Management and Portola Pharmaceuticals Inc (PTLA)

1.

NAME OF REPORTING PERSON

S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

Partner Fund Management GP, LLC

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a)      ¨

(b)     x

3.

SEC USE ONLY

4.

CITIZENSHIP OR PLACE OF ORGANIZATION

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH

5.

SOLE VOTING POWER

0

6.

SHARED VOTING POWER

3,230,997 shares

7.

SOLE DISPOSITIVE POWER

0

8.

SHARED DISPOSITIVE POWER

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

See Row 6 above

10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

5.7%

12.

TYPE OF REPORTING PERSON

OO