BAKER BROS. ADVISORS LP Information

667 MADISON AVE, NEW YORK, New York, 10065, (212) 339-5600

Report Date: 12/31/2013

Position Statistics

Total Positions 88
New Positions 14
Increased Positions 31
Decreased Positions 21
Positions with Activity 52
Sold Out Positions 4
Total Mkt Value (in $ millions) 5,103

Institutional Holdings information is filed by major institutions on form 13-F with the Securities and Exchange Commission.

Sector Weighting

Basic Materials
Capital Goods
Conglomerates 1.34%
Consumer Cyclical
Consumer/Non-Cyclical
Energy
Financial
Healthcare 97.79%
Services
Technology
Transportation
Utilities

88 Positions as of 12/31/2013

Company Class Value of Shares ($1,000s) Change in Value ($1,000s) Change (%) ▲ Shares Held
ARIAD PHARMACEUTICALS INC COM -9,856 Sold Out 0
CUBIST PHARMACEUTICALS INC COM -326 Sold Out 0
MEI PHARMA INC COM NEW -2,990 Sold Out 0
TARGACEPT INC COM -8,459 Sold Out 0
CHEMOCENTRYX INC COM 274 -822 (75) 50,000
PUMA BIOTECHNOLOGY INC COM 1,910 -5,729 (75) 25,000
UNITED THERAPEUTICS CORP DEL COM 1,924 -3,461 (64.28) 20,000
GERON CORP COM 769 -1,141 (59.74) 402,629
GILEAD SCIENCES INC COM 39,817 -49,382 (55.36) 556,108
IDERA PHARMACEUTICALS INC COM NEW 9,008 -7,649 (45.92) 3,171,765
AEGERION PHARMACEUTICALS INC COM 22,000 -14,092 (39.05) 500,000
PORTOLA PHARMACEUTICALS INC COM 5,474 -1,841 (25.17) 224,434
NOVAVAX INC COM 5,366 -1,793 (25.05) 1,286,913
INSMED INC COM PAR $.01 11,508 -2,159 (15.8) 796,378
STEMLINE THERAPEUTICS INC COM 10,787 -2,003 (15.66) 675,042
ENANTA PHARMACEUTICALS INC COM 3,741 -545 (12.72) 109,097
HALOZYME THERAPEUTICS INC COM 48,424 -5,541 (10.27) 6,297,026
PROTHENA CORP PLC SHS 10,657 -1,035 (8.86) 336,918
PHARMACYCLICS INC COM 776,010 -25,898 (3.23) 8,719,218
ARROWHEAD RESH CORP COM NEW 40,603 -657 (1.59) 3,090,000