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
ABBVIE INC	COM	00287Y109	55,590	600,000	SH		SOLE		600,000	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	51,281	1,253,500	SH		SOLE		1,253,500	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	6,651	2,350,000	SH		SOLE		2,350,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	17,094	856,000	SH		SOLE		856,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	8,903	750,000	SH		SOLE		750,000	0	0
ADVERUM BIOTECHNOLOGIES INC	COM	00773U108	4,770	900,000	SH		SOLE		900,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	6,877	650,000	SH		SOLE		650,000	0	0
AGILENT TECHNOLOGIES INC	COM	00846U101	10,123	163,700	SH		SOLE		163,700	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	24,727	1,565,000	SH		SOLE		1,565,000	0	0
ALDER BIOPHARMACEUTICALS INC	NOTE 2.500% 2/0	014339AA3	5,207	5,000,000	PRN		SOLE		5,000,000	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	61,144	492,500	SH		SOLE		492,500	0	0
ALIGN TECHNOLOGY INC	COM	016255101	22,581	66,000	SH		SOLE		66,000	0	0
ALLERGAN PLC	SHS	G0177J108	2,945	17,665	SH		SOLE		17,665	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	17,088	173,500	SH		SOLE		173,500	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	12,360	4,000,000	SH		SOLE		4,000,000	0	0
AMERISOURCEBERGEN CORP	COM	03073E105	18,759	220,000	SH		SOLE		220,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	15,620	1,000,000	SH		SOLE		1,000,000	0	0
ANAPTYSBIO INC	COM	032724106	10,656	150,000	SH		SOLE		150,000	0	0
APTINYX INC	COM	03836N103	8,218	340,000	SH		SOLE		340,000	0	0
ARDELYX INC	COM	039697107	9,345	2,525,557	SH		SOLE		2,525,557	0	0
ARENA PHARMACEUTICALS INC	COM NEW	040047607	16,350	375,000	SH		SOLE		375,000	0	0
ARGENX SE	SPONSORED ADR	04016X101	10,668	128,750	SH		SOLE		128,750	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	16,198	243,500	SH		SOLE		243,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	17,645	450,000	SH		SOLE		450,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	16,812	440,000	SH		SOLE		440,000	0	0
AXOGEN INC	COM	05463X106	27,386	545,000	SH		SOLE		545,000	0	0
BAXTER INTL INC	COM	071813109	21,930	297,000	SH		SOLE		297,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	33,052	215,000	SH		SOLE		215,000	0	0
BIOCRYST PHARMACEUTICALS	COM	09058V103	1,433	250,000	SH		SOLE		250,000	0	0
BIOGEN INC	COM	09062X103	15,383	53,000	SH		SOLE		53,000	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	15,709	397,500	SH		SOLE		397,500	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	11,775	125,000	SH		SOLE		125,000	0	0
BLUEBIRD BIO INC	COM	09609G100	7,063	45,000	SH		SOLE		45,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	12,633	199,000	SH		SOLE		199,000	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	5,641	172,500	SH		SOLE		172,500	0	0
CELGENE CORP	COM	151020104	28,623	360,400	SH		SOLE		360,400	0	0
CHIASMA INC	COM	16706W102	788	525,000	SH		SOLE		525,000	0	0
CIDARA THERAPEUTICS INC	COM	171757107	1,560	300,000	SH		SOLE		300,000	0	0
CLEARSIDE BIOMEDICAL INC	COM	185063104	10,423	975,000	SH		SOLE		975,000	0	0
CLEMENTIA PHARMACEUTICALS IN	COM	185575107	4,540	345,000	SH		SOLE		345,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	11,595	255,000	SH		SOLE		255,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	9,660	690,000	SH		SOLE		690,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	39,353	1,650,000	SH		SOLE		1,650,000	0	0
COMPUGEN LTD	ORD	M25722105	3,558	1,078,165	SH		SOLE		1,078,165	0	0
CORREVIO PHARMA CORP	COM	22026V105	4,536	1,200,000	SH		SOLE		1,200,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	6,314	575,000	SH		SOLE		575,000	0	0
CYMABAY THERAPEUTICS INC	COM	23257D103	7,784	580,000	SH		SOLE		580,000	0	0
DAVITA INC	COM	23918K108	28,366	408,500	SH		SOLE		408,500	0	0
DERMIRA INC	COM	24983L104	5,520	600,000	SH		SOLE		600,000	0	0
DERMIRA INC	NOTE 3.000% 5/1	24983LAB0	827	1,000,000	PRN		SOLE		1,000,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	4,087	268,000	SH		SOLE		268,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	24,019	165,000	SH		SOLE		165,000	0	0
EGALET CORP	NOTE 5.500% 4/0	28226BAB0	2,841	7,800,000	PRN		SOLE		7,800,000	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	30,474	450,000	SH		SOLE		450,000	0	0
ENDOCYTE INC	COM	29269A102	9,315	675,000	SH		SOLE		675,000	0	0
ENVISION HEALTHCARE CORP	COM	29414D100	4,854	110,300	SH		SOLE		110,300	0	0
EPIZYME INC	COM	29428V104	16,819	1,241,253	SH		SOLE		1,241,253	0	0
EXACT SCIENCES CORP	COM	30063P105	22,720	380,000	SH		SOLE		380,000	0	0
EXELIXIS INC	COM	30161Q104	12,804	595,000	SH		SOLE		595,000	0	0
FIBROGEN INC	COM	31572Q808	19,218	307,000	SH		SOLE		307,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	9,375	593,000	SH		SOLE		593,000	0	0
G1 THERAPEUTICS INC	COM	3621LQ109	13,038	300,000	SH		SOLE		300,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	17,053	185,000	SH		SOLE		185,000	0	0
GILEAD SCIENCES INC	COM	375558103	25,857	365,000	SH		SOLE		365,000	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	6,780	150,000	SH		SOLE		150,000	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	8,351	880,000	SH		SOLE		880,000	0	0
GTX INC DEL	COM NEW	40052B207	5,420	354,000	SH		SOLE		354,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	61,398	440,000	SH		SOLE		440,000	0	0
HCA HEALTHCARE INC	COM	40412C101	44,118	430,000	SH		SOLE		430,000	0	0
HERON THERAPEUTICS INC	COM	427746102	20,396	525,000	SH		SOLE		525,000	0	0
HOLOGIC INC	COM	436440101	15,900	400,000	SH		SOLE		400,000	0	0
HOMOLOGY MEDICINES INC	COM	438083107	9,588	470,000	SH		SOLE		470,000	0	0
IDEXX LABS INC	COM	45168D104	15,692	72,000	SH		SOLE		72,000	0	0
IMMUNOMEDICS INC	COM	452907108	11,835	500,000	SH		SOLE		500,000	0	0
INCYTE CORP	COM	45337C102	19,832	296,000	SH		SOLE		296,000	0	0
INOGEN INC	COM	45780L104	22,173	119,000	SH		SOLE		119,000	0	0
INSMED INC	COM PAR $.01	457669307	19,511	825,000	SH		SOLE		825,000	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	5,531	6,000,000	PRN		SOLE		6,000,000	0	0
INTERSECT ENT INC	COM	46071F103	15,355	410,000	SH		SOLE		410,000	0	0
INTRA CELLULAR THERAPIES INC	COM	46116X101	3,313	187,500	SH		SOLE		187,500	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	67,896	141,900	SH		SOLE		141,900	0	0
INVITAE CORP	COM	46185L103	10,290	1,400,000	SH		SOLE		1,400,000	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	38,942	480,000	SH		SOLE		480,000	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	16,885	98,000	SH		SOLE		98,000	0	0
KINIKSA PHARMACEUTICALS LTD	COM CL A	G5269C101	1,562	90,000	SH		SOLE		90,000	0	0
KURA ONCOLOGY INC	COM	50127T109	7,280	400,000	SH		SOLE		400,000	0	0
LA JOLLA PHARMACEUTICAL CO	COM PAR $.0001 2	503459604	6,484	222,300	SH		SOLE		222,300	0	0
LOXO ONCOLOGY INC	COM	548862101	50,292	289,900	SH		SOLE		289,900	0	0
MACROGENICS INC	COM	556099109	5,679	275,000	SH		SOLE		275,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	95,738	342,300	SH		SOLE		342,300	0	0
MCKESSON CORP	COM	58155Q103	667	5,000	SH		SOLE		5,000	0	0
MEDICINES CO	COM	584688105	25,323	690,000	SH		SOLE		690,000	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	3,660	3,000,000	PRN		SOLE		3,000,000	0	0
MEDICINES CO	NOTE 2.750% 7/1	584688AG0	5,052	5,000,000	PRN		SOLE		5,000,000	0	0
MENLO THERAPEUTICS INC	COM	586858102	2,680	330,000	SH		SOLE		330,000	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	17,860	1,000,000	SH		SOLE		1,000,000	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	11,832	240,000	SH		SOLE		240,000	0	0
MOLINA HEALTHCARE INC	COM	60855R100	53,377	545,000	SH		SOLE		545,000	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	9,254	452,500	SH		SOLE		452,500	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	6,749	295,100	SH		SOLE		295,100	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	2,227	640,000	SH		SOLE		640,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	61,930	630,400	SH		SOLE		630,400	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,446	1,000,000	PRN		SOLE		1,000,000	0	0
NOVAVAX INC	COM	670002104	4,355	3,250,000	SH		SOLE		3,250,000	0	0
NUVASIVE INC	COM	670704105	19,415	372,500	SH		SOLE		372,500	0	0
OBSEVA SA	COM	H5861P103	16,957	1,120,000	SH		SOLE		1,120,000	0	0
ODONATE THERAPEUTICS INC	COM	676079106	8,782	397,750	SH		SOLE		397,750	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	38,396	1,198,000	SH		SOLE		1,198,000	0	0
PACIRA PHARMACEUTICALS INC	NOTE 2.375% 4/0	695127AD2	932	1,000,000	PRN		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	4,590	450,000	SH		SOLE		450,000	0	0
PENUMBRA INC	COM	70975L107	32,707	236,750	SH		SOLE		236,750	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	12,230	323,800	SH		SOLE		323,800	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	26,911	288,247	SH		SOLE		288,247	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	1,315	471,321	SH		SOLE		471,321	0	0
PROTHENA CORP PLC	SHS	G72800108	1,239	85,000	SH	Call	SOLE		85,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	28,144	475,800	SH		SOLE		475,800	0	0
RA PHARMACEUTICALS INC	COM	74933V108	7,463	750,000	SH		SOLE		750,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	33,154	1,125,000	SH		SOLE		1,125,000	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,399	1,500,000	PRN		SOLE		1,500,000	0	0
RESTORBIO INC	COM	76133L103	2,516	275,000	SH		SOLE		275,000	0	0
RETROPHIN INC	COM	761299106	10,904	400,000	SH		SOLE		400,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	6,721	215,000	SH		SOLE		215,000	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	11,179	3,950,000	SH		SOLE		3,950,000	0	0
RTI SURGICAL INC	COM	74975N105	8,970	1,950,000	SH		SOLE		1,950,000	0	0
SAGE THERAPEUTICS INC	COM	78667J108	7,670	49,000	SH		SOLE		49,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	39,324	297,500	SH		SOLE		297,500	0	0
SCYNEXIS INC	COM	811292101	1,345	820,000	SH		SOLE		820,000	0	0
SERES THERAPEUTICS INC	COM	81750R102	1,892	220,000	SH		SOLE		220,000	0	0
SOLID BIOSCIENCES INC	COM	83422E105	3,385	95,000	SH		SOLE		95,000	0	0
SPARK THERAPEUTICS INC	COM	84652J103	45,021	544,000	SH		SOLE		544,000	0	0
SPERO THERAPEUTICS INC	COM	84833T103	7,702	525,000	SH		SOLE		525,000	0	0
STRYKER CORP	COM	863667101	30,057	178,000	SH		SOLE		178,000	0	0
TELEFLEX INC	COM	879369106	24,809	92,500	SH		SOLE		92,500	0	0
TESARO INC	COM	881569107	27,812	625,400	SH		SOLE		625,400	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,491	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	14,801	652,600	SH		SOLE		652,600	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	19,885	96,000	SH		SOLE		96,000	0	0
TRANSLATE BIO INC	COM	89374L104	12,790	1,011,079	SH		SOLE		1,011,079	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	15,374	200,000	SH		SOLE		200,000	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	139,230	567,500	SH		SOLE		567,500	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	32,377	190,500	SH		SOLE		190,500	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	54,912	223,000	SH		SOLE		223,000	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	15,886	160,000	SH		SOLE		160,000	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	25,960	1,000,000	SH		SOLE		1,000,000	0	0
ZAI LAB LTD	ADR	98887Q104	6,975	300,000	SH		SOLE		300,000	0	0
ZIMMER BIOMET HLDGS INC	COM	98956P102	17,942	161,000	SH		SOLE		161,000	0	0
ZOGENIX INC	COM NEW	98978L204	9,989	226,000	SH		SOLE		226,000	0	0