Dark
Light
System
Institutional Investment Manager
Rock Springs Capital Management LP
Rock Springs Capital Management LP (CIK: 0001595725) incorporated in Delaware, located at 650 South Exeter Street, Baltimore, MD. Institutional holdings reported to the SEC.

Institutional Holdings (2017Q1)
Portfolio Summary: 140 holdings with a total value of $1,733,063,000.
#
Name
Shares
Value ($)
%
Options
Notes
1 TESARO INCORPORATED 474,900 73,073,000 4.22%
2 ACADIA COMPANY COM 1,275,000 55,590,000 3.21%
3 ALEXION PHARMACEUTIC 456,900 55,395,000 3.20%
4 MERCK & CO INC 750,000 47,655,000 2.75%
5 PACIRA PHARMACEUTICALS INC 1,000,000 45,600,000 2.63%
6 GW PHARMACEUTICALS PLC 356,500 43,115,000 2.49%
7 ALLERGAN PLC 166,000 39,661,000 2.29%
8 CIGNA CORPORATION 270,000 39,552,000 2.28%
9 INTUITIVE SURGICAL INC 48,000 36,791,000 2.12%
10 RADIUS HEALTH INCORPORATED COM NEW 910,250 35,181,000 2.03%
11 MEDICINES CO 700,000 34,230,000 1.98%
12 ADVANCED ACCELERATOR APPLIC 850,000 33,881,000 1.95%
13 SPARK THERAPEUTICS INCORPORATED 625,000 33,338,000 1.92%
14 WELLCARE HEALTH PLANS INC 234,500 32,879,000 1.90%
15 CELGENE CORP 242,500 30,174,000 1.74%
16 PRA HEALTH SCIENCES INC 457,500 29,843,000 1.72%
17 AETNA INC NEW 220,000 28,061,000 1.62%
18 LILLY ELI & CO 325,000 27,336,000 1.58%
19 HUMANA INC 132,500 27,314,000 1.58%
20 UNITEDHEALTH GROUP INC 165,000 27,062,000 1.56%
21 PENUMBRA INC COM 310,500 25,911,000 1.50%
22 ARDELYX INC COM 2,000,000 25,300,000 1.46%
23 BRISTOL MYERS SQUIBB CO 452,600 24,612,000 1.42%
24 SHIRE PLC 138,900 24,201,000 1.40%
25 INCYTE CORP 169,000 22,590,000 1.30%
26 Theravance Biopharma Inc 600,000 22,092,000 1.27%
27 JOHNSON & JOHNSON 175,000 21,796,000 1.26%
28 Wright Medical Group NV 670,000 20,850,000 1.20%
29 ACLARIS THERAPEUTICS INC COM 675,000 20,129,000 1.16%
30 GILEAD SCIENCES INC 286,500 19,459,000 1.12%
31 GALAPAGOS NV 210,000 18,100,000 1.04%
32 JAZZ PHARMACEUTICALS PLC 123,700 17,953,000 1.04%
33 NEUROCRINE BIOSCIE COM USD0.001 410,000 17,753,000 1.02%
34 PROTHENA CORP PLC 309,500 17,267,000 1.00%
35 COLLEGIUM PHARMACEUTICAL INC COM 1,700,000 17,102,000 0.99%
36 RA PHARMACEUTICALS INC COM 788,959 16,797,000 0.97%
37 AMGEN INC 98,000 16,079,000 0.93%
38 AMARIN CORP PLC 5,001,200 16,004,000 0.92%
39 HOLOGIC INC 340,000 14,467,000 0.83%
40 WILLIS TOWERS WATSON PUB LTD 110,000 14,398,000 0.83%
41 COHERUS BIOSCIENCES INC COM 675,000 14,276,000 0.82%
42 DANAHER CORP DEL 160,000 13,685,000 0.79%
43 EDWARDS LIFESCIENCES CORP 142,500 13,405,000 0.77%
44 WALGREENS BOOTS ALLIANCE INC 161,000 13,371,000 0.77%
45 INVITAE CORP 1,200,000 13,272,000 0.77%
46 DERMIRA INC COM 387,600 13,221,000 0.76%
47 BIOGEN INC 48,000 13,124,000 0.76%
48 CLOVIS ONCOLOGY INC 184,500 11,747,000 0.68%
49 THERAPEUTICSMD INC 1,600,000 11,520,000 0.66%
50 HEALTHSOUTH CORP 265,000 11,345,000 0.65%
Page 1 of 3

Portfolio data is normalized using SEC Form 13F filings, including the Original 13F-HR (0001172661-17-001168, filed 2017.05.15).

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.