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Institutional Investment Manager
DEERFIELD MANAGEMENT COMPANY, L.P.
DEERFIELD MANAGEMENT COMPANY, L.P. (CIK: 0001009258) incorporated in Delaware, located at 345 Park Avenue South, 12th Floor, New York, NY. Institutional holdings reported to the SEC.

Institutional Holdings (2015Q4)
Portfolio Summary: 109 holdings with a total value of $2,467,381,000.
#
Name
Shares
Value ($)
%
Options
Notes
1 HORIZON PHARMA PLC 11,684,801 253,210,000 10.26%
2 NXSTAGE MED INC COM 4,589,000 100,545,000 4.07%
3 DYAX CORP COM CVR 2,242,073 84,347,000 3.42%
4 Adeptus Health Inc 1,307,908 71,307,000 2.89%
5 GLAXOSMITHKLINE PLC 1,675,385 67,602,000 2.74%
6 AETNA INC NEW 591,465 63,949,000 2.59%
7 DAVITA INC 822,000 57,302,000 2.32%
8 MYLAN N V 1,056,000 57,098,000 2.31%
9 VANDA PHARMACEUTICALS INC COM 5,996,691 55,829,000 2.26%
10 GILEAD SCIENCES INC 532,000 53,833,000 2.18% Call
11 TEVA PHARMACEUTICAL INDS LTD 815,000 53,497,000 2.17%
12 FLAMEL TECHNOLOGIES SA SPONSORED ADR 4,072,809 49,729,000 2.02%
13 HEALTHWAYS INC 51,925,000 49,087,000 1.99% PRN
14 ARRAY BIOPHARMA INC 3 06/01/2020 45,000,000 42,292,000 1.71% PRN
15 GLOBAL BLOOD THERAPEUTICS IN COM 1,163,811 37,626,000 1.52%
16 HEARTWARE INTL INC 39,226,000 37,364,000 1.51% PRN
17 ARRAY BIOPHARMA INC COM 8,729,361 36,838,000 1.49%
18 TEVA PHARMACEUTICAL INDS LTD 550,000 36,102,000 1.46% Call
19 PORTOLA PHARMACEUTICALS INC 683,749 35,179,000 1.43%
20 SAGE THERAPEUTICS 598,854 34,913,000 1.41%
21 ENDOLOGIX INC 40,941,000 34,602,000 1.40% PRN
22 XENOPORT INC 6,287,374 34,518,000 1.40%
23 AAC HLDGS INC COM 1,782,094 33,967,000 1.38%
24 INFINITY PHARMACEUTICALS INC COM 4,305,288 33,797,000 1.37%
25 UNIVERSAL AMERN CORP NEW 4,789,027 33,523,000 1.36%
26 WALGREENS BOOTS ALLIANCE INC 386,457 32,909,000 1.33%
27 EHEALTH INC COM 3,264,588 32,581,000 1.32%
28 ENDOLOGIX INC 30,000,000 32,548,000 1.32% PRN
29 HEALTHWAYS INC 2,465,042 31,725,000 1.29%
30 ACCURAY INC 30,511,000 30,875,000 1.25% PRN
31 CHARLES RIV LABS INTL INC 377,188 30,322,000 1.23%
32 Nivalis Therapeutics Inc 3,732,412 28,889,000 1.17%
33 MCKESSON CORP 144,646 28,529,000 1.16%
34 GENOMIC HEALTH INC COM 809,432 28,492,000 1.15%
35 PACIRA BIOSCIENCES INC 371,000 28,489,000 1.15%
36 FIVE PRIME THERAPEUTICS INC 680,000 28,220,000 1.14%
37 KEMPHARM INC 1,420,497 28,211,000 1.14%
38 ProNAi Therapeutics, Inc. 1,791,255 26,940,000 1.09%
39 RELYPSA INC 900,281 25,514,000 1.03%
40 SPECTRANETICS CORP 29,831,000 22,537,000 0.91% PRN
41 GW PHARMACEUTICALS PLC 310,122 21,535,000 0.87%
42 CYTOMX THERAPEUTICS INC COM 946,022 19,743,000 0.80%
43 AERIE PHARMACEUTICALS INC 807,875 19,672,000 0.80%
44 Proteon Therapeutics 1,265,343 19,625,000 0.80%
45 RITE AID CORP 2,492,772 19,543,000 0.79%
46 REGENXBIO INC COM 1,169,042 19,406,000 0.79%
47 XENCOR INC COM 1,256,612 18,372,000 0.74%
48 PACIFIC BIOSCIENCES CALIF IN 1,388,000 18,224,000 0.74%
49 ACHILLION PHARMACEUTICALS INC COM 1,667,000 17,987,000 0.73%
50 FLUIDIGM CORP DEL 27,715,000 17,603,000 0.71% PRN
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Portfolio data is normalized using SEC Form 13F filings, including the Original 13F-HR (0001140361-16-053179, filed 2016.02.16).

From 2023-01-03 onward, the SEC requires values to be reported in nearest dollars. Earlier filings reported values in thousands; therefore, positions shown as $0 in older filings may represent actual values between $0–$999.