13G Filing: Partner Fund Management and Puma Biotechnology Inc. (PBYI)

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Page 2 of 13 – SEC Filing

CUSIP No. 74587V107 13G Page 2 of 13 Pages

1.

NAME OF REPORTING PERSON

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

Partner Fund Management, L.P.

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

 

2,971,970 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)

8.0%1

12.

TYPE OF REPORTING PERSON

IA; PN

1 The percentages reported in this Schedule 13G are based upon 36,966,278 shares of common stock outstanding as of May 4, 2017 according Form 10-Q filed
by the issuer with the Securities and Exchange Commission on May 10, 2017. All of the other
numbers and percentages reported in this Schedule 13G are as of 9:00 a.m. (ET) on the date of filing.

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