Rock Springs Capital Management 13F-HR Quarterly holdings report by institutional manager

The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE

OMB APPROVAL

OMB Number:		3235-0006
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COLUMN 1	COLUMN 2	COLUMN 3	COLUMN 4	COLUMN 5			COLUMN 6	COLUMN 7	COLUMN 8
			VALUE	SHRS OR	SH/	PUT/	INVESTMENT	OTHER	VOTING AUTHORITY
NAME OF ISSUER	TITLE OF CLASS	CUSIP	(x$1000)	PRN AMT	PRN	CALL	DISCRETION	MANAGER	SOLE	SHARED	NONE
ABLYNX NV	SPONSORED ADR	00372Y105	6,248	250,000	SH		SOLE		250,000	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	40,902	1,253,500	SH		SOLE		1,253,500	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	6,480	2,250,000	SH		SOLE		2,250,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	10,234	415,000	SH		SOLE		415,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	5,845	875,000	SH		SOLE		875,000	0	0
ADURO BIOTECH INC	COM	00739L101	3,113	415,000	SH		SOLE		415,000	0	0
ADVANCED ACCELERATOR APPLIC	SPONSORED ADS	00790T100	67,377	825,500	SH		SOLE		825,500	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	2,835	524,089	SH		SOLE		524,089	0	0
AETNA INC NEW	COM	00817Y108	43,113	239,000	SH		SOLE		239,000	0	0
AIMMUNE THERAPEUTICS INC	COM	00900T107	11,081	293,000	SH		SOLE		293,000	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	12,080	1,055,000	SH		SOLE		1,055,000	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	57,403	480,000	SH		SOLE		480,000	0	0
ALIGN TECHNOLOGY INC	COM	016255101	14,831	66,750	SH		SOLE		66,750	0	0
ALLERGAN PLC	5.5% CNV PFD A	G0177J116	2,934	5,000	SH		SOLE		5,000	0	0
ALMOST FAMILY INC	COM	020409108	8,166	147,540	SH		SOLE		147,540	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	16,517	130,000	SH		SOLE		130,000	0	0
ALPINE IMMUNE SCIENCES INC	COM	02083G100	1,680	150,000	SH		SOLE		150,000	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	15,840	3,950,000	SH		SOLE		3,950,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	13,095	910,000	SH		SOLE		910,000	0	0
ANAPTYSBIO INC	COM	032724106	14,343	142,400	SH		SOLE		142,400	0	0
ARDELYX INC	COM	039697107	15,019	2,275,557	SH		SOLE		2,275,557	0	0
ARENA PHARMACEUTICALS INC	COM NEW	040047607	7,304	215,000	SH		SOLE		215,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	11,217	280,000	SH		SOLE		280,000	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	20,363	450,000	SH		SOLE		450,000	0	0
ATYR PHARMA INC	COM	002120103	1,663	475,000	SH		SOLE		475,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	16,406	525,000	SH		SOLE		525,000	0	0
AVEXIS INC	COM	05366U100	19,367	175,000	SH		SOLE		175,000	0	0
AXOGEN INC	COM	05463X106	13,513	477,500	SH		SOLE		477,500	0	0
BAXTER INTL INC	COM	071813109	14,867	230,000	SH		SOLE		230,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	25,994	266,000	SH		SOLE		266,000	0	0
BIOCRYST PHARMACEUTICALS	COM	09058V103	3,989	812,500	SH		SOLE		812,500	0	0
BIOGEN INC	COM	09062X103	16,884	53,000	SH		SOLE		53,000	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	6,583	244,000	SH		SOLE		244,000	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	11,146	125,000	SH		SOLE		125,000	0	0
BLUEBIRD BIO INC	COM	09609G100	8,015	45,000	SH		SOLE		45,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	11,048	146,500	SH		SOLE		146,500	0	0
BRISTOL MYERS SQUIBB CO	COM	110122108	3,064	50,000	SH		SOLE		50,000	0	0
CARDIOME PHARMA CORP	COM NO PAR	14159U301	1,860	1,200,000	SH		SOLE		1,200,000	0	0
CELGENE CORP	COM	151020104	31,621	303,000	SH		SOLE		303,000	0	0
CHIASMA INC	COM	16706W102	893	525,000	SH		SOLE		525,000	0	0
CHINA CORD BLOOD CORP	SHS	G21107100	8,756	880,000	SH		SOLE		880,000	0	0
CIDARA THERAPEUTICS INC	COM	171757107	2,040	300,000	SH		SOLE		300,000	0	0
CIGNA CORPORATION	COM	125509109	65,192	321,000	SH		SOLE		321,000	0	0
CLEARSIDE BIOMEDICAL INC	COM	185063104	6,545	935,000	SH		SOLE		935,000	0	0
CLEMENTIA PHARMACEUTICALS IN	COM	185575107	6,548	345,000	SH		SOLE		345,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	15,742	231,500	SH		SOLE		231,500	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	5,540	629,500	SH		SOLE		629,500	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	34,811	1,885,729	SH		SOLE		1,885,729	0	0
COMPUGEN LTD	ORD	M25722105	2,063	825,000	SH		SOLE		825,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	4,378	422,600	SH		SOLE		422,600	0	0
CYMABAY THERAPEUTICS INC	COM	23257D103	4,140	450,000	SH		SOLE		450,000	0	0
DARE BIOSCIENCE INC	COM	23666P101	135	62,500	SH		SOLE		62,500	0	0
DAVITA INC	COM	23918K108	5,787	80,100	SH		SOLE		80,100	0	0
DBV TECHNOLOGIES S A	SPONSORED ADR	23306J101	1,796	73,000	SH		SOLE		73,000	0	0
DERMIRA INC	COM	24983L104	11,680	420,000	SH		SOLE		420,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	3,273	175,000	SH		SOLE		175,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	21,415	190,001	SH		SOLE		190,001	0	0
EGALET CORP	NOTE 5.500% 4/0	28226BAB0	3,754	7,800,000	PRN		SOLE		7,800,000	0	0
EPIZYME INC	COM	29428V104	16,629	1,325,000	SH		SOLE		1,325,000	0	0
EXACT SCIENCES CORP	COM	30063P105	22,850	434,900	SH		SOLE		434,900	0	0
EXELIXIS INC	COM	30161Q104	5,320	175,000	SH		SOLE		175,000	0	0
FIBROGEN INC	COM	31572Q808	15,405	325,000	SH		SOLE		325,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	9,316	425,000	SH		SOLE		425,000	0	0
G1 THERAPEUTICS INC	COM	3621LQ109	4,256	214,500	SH		SOLE		214,500	0	0
GALAPAGOS NV	SPON ADR	36315X101	17,346	185,000	SH		SOLE		185,000	0	0
GILEAD SCIENCES INC	COM	375558103	22,452	313,400	SH		SOLE		313,400	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	5,903	150,000	SH		SOLE		150,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	46,732	354,000	SH		SOLE		354,000	0	0
HEALTHEQUITY INC	COM	42226A107	9,099	195,000	SH		SOLE		195,000	0	0
HEALTHSOUTH CORP	COM NEW	421924309	13,094	265,000	SH		SOLE		265,000	0	0
HERON THERAPEUTICS INC	COM	427746102	4,525	250,000	SH		SOLE		250,000	0	0
HOLOGIC INC	COM	436440101	14,321	335,000	SH		SOLE		335,000	0	0
INCYTE CORP	COM	45337C102	17,285	182,500	SH		SOLE		182,500	0	0
INFINITY PHARMACEUTICALS INC	COM	45665G303	548	270,000	SH		SOLE		270,000	0	0
INOGEN INC	COM	45780L104	9,526	80,000	SH		SOLE		80,000	0	0
INSMED INC	COM PAR $.01	457669307	19,129	613,500	SH		SOLE		613,500	0	0
INTERSECT ENT INC	COM	46071F103	11,178	345,000	SH		SOLE		345,000	0	0
INTRA CELLULAR THERAPIES INC	COM	46116X101	2,715	187,500	SH		SOLE		187,500	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	52,515	143,900	SH		SOLE		143,900	0	0
INVITAE CORP	COM	46185L103	11,858	1,306,000	SH		SOLE		1,306,000	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	22,756	406,000	SH		SOLE		406,000	0	0
IRONWOOD PHARMACEUTICALS INC	COM CL A	46333X108	3,373	225,000	SH		SOLE		225,000	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	16,656	123,700	SH		SOLE		123,700	0	0
JOHNSON & JOHNSON	COM	478160104	27,944	200,000	SH		SOLE		200,000	0	0
JUNO THERAPEUTICS INC	COM	48205A109	10,513	230,000	SH		SOLE		230,000	0	0
LOXO ONCOLOGY INC	COM	548862101	26,096	310,000	SH		SOLE		310,000	0	0
MACROGENICS INC	COM	556099109	4,275	225,000	SH		SOLE		225,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	31,392	342,000	SH		SOLE		342,000	0	0
MEDICINES CO	COM	584688105	18,865	690,000	SH		SOLE		690,000	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	3,171	3,000,000	PRN		SOLE		3,000,000	0	0
MEDICINES CO	NOTE 2.750% 7/1	584688AG0	4,597	5,000,000	PRN		SOLE		5,000,000	0	0
MERCK & CO INC	COM	58933Y105	47,869	850,700	SH		SOLE		850,700	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	21,799	1,326,800	SH		SOLE		1,326,800	0	0
MERUS N V	COM	N5749R100	5,276	271,952	SH		SOLE		271,952	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	3,285	180,000	SH		SOLE		180,000	0	0
MOLINA HEALTHCARE INC	COM	60855R100	43,478	567,000	SH		SOLE		567,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	3,730	295,100	SH		SOLE		295,100	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	3,738	625,000	SH		SOLE		625,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	37,709	486,000	SH		SOLE		486,000	0	0
NOVAVAX INC	COM	670002104	2,480	2,000,000	SH		SOLE		2,000,000	0	0
OBSEVA SA	COM	H5861P103	8,198	840,000	SH		SOLE		840,000	0	0
ODONATE THERAPEUTICS INC	COM	676079106	10,250	410,000	SH		SOLE		410,000	0	0
OREXIGEN THERAPEUTICS INC	COM NEW	686164302	213	165,300	SH		SOLE		165,300	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	50,521	1,106,700	SH		SOLE		1,106,700	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	8,055	450,000	SH		SOLE		450,000	0	0
PENUMBRA INC	COM	70975L107	29,218	310,500	SH		SOLE		310,500	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	15,763	323,800	SH		SOLE		323,800	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	43,486	477,500	SH		SOLE		477,500	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	3,935	675,000	SH		SOLE		675,000	0	0
PROTHENA CORP PLC	SHS	G72800108	11,622	310,000	SH		SOLE		310,000	0	0
PROTHENA CORP PLC	SHS	G72800108	937	25,000	SH	Call	SOLE		25,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	36,920	373,500	SH		SOLE		373,500	0	0
RA PHARMACEUTICALS INC	COM	74933V108	5,100	600,000	SH		SOLE		600,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	29,959	943,000	SH		SOLE		943,000	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,418	1,500,000	PRN		SOLE		1,500,000	0	0
RETROPHIN INC	COM	761299106	8,428	400,000	SH		SOLE		400,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	2,078	71,500	SH		SOLE		71,500	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	9,603	2,475,000	SH		SOLE		2,475,000	0	0
RTI SURGICAL INC	COM	74975N105	7,995	1,950,000	SH		SOLE		1,950,000	0	0
SAGE THERAPEUTICS INC	COM	78667J108	7,412	45,000	SH		SOLE		45,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	14,355	258,000	SH		SOLE		258,000	0	0
SCYNEXIS INC	COM	811292101	1,763	760,000	SH		SOLE		760,000	0	0
SEATTLE GENETICS INC	COM	812578102	6,688	125,000	SH		SOLE		125,000	0	0
SERES THERAPEUTICS INC	COM	81750R102	2,231	220,000	SH		SOLE		220,000	0	0
SPARK THERAPEUTICS INC	COM	84652J103	31,623	615,000	SH		SOLE		615,000	0	0
SPERO THERAPEUTICS INC	COM	84833T103	6,169	525,000	SH		SOLE		525,000	0	0
STERIS PLC	SHS USD	G84720104	6,473	74,000	SH		SOLE		74,000	0	0
STRYKER CORP	COM	863667101	19,587	126,500	SH		SOLE		126,500	0	0
TELEFLEX INC	COM	879369106	22,829	91,750	SH		SOLE		91,750	0	0
TESARO INC	COM	881569107	45,454	548,500	SH		SOLE		548,500	0	0
TETRAPHASE PHARMACEUTICALS I	COM	88165N105	5,985	950,000	SH		SOLE		950,000	0	0
THERAPEUTICSMD INC	COM	88338N107	7,097	1,175,000	SH		SOLE		1,175,000	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,645	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	18,201	652,600	SH		SOLE		652,600	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	20,887	110,000	SH		SOLE		110,000	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	7,560	163,000	SH		SOLE		163,000	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	107,364	487,000	SH		SOLE		487,000	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	25,664	171,250	SH		SOLE		171,250	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	26,949	134,000	SH		SOLE		134,000	0	0
WILLIS TOWERS WATSON PUB LTD	SHS	G96629103	18,535	123,000	SH		SOLE		123,000	0	0
WRIGHT MED GROUP INC	NOTE 2.000% 2/1	98235TAE7	1,031	1,000,000	PRN		SOLE		1,000,000	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	15,540	700,000	SH		SOLE		700,000	0	0
ZAI LAB LTD	ADR	98887Q104	6,263	295,000	SH		SOLE		295,000	0	0
ZIMMER BIOMET HLDGS INC	COM	98956P102	14,360	119,000	SH		SOLE		119,000	0	0
ZOGENIX INC	COM NEW	98978L204	9,031	225,500	SH		SOLE		225,500	0	0