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
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	27,112	925,000	SH		SOLE		925,000	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	7,992	2,700,000	SH		SOLE		2,700,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	10,183	1,700,000	SH		SOLE		1,700,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	3,440	800,000	SH		SOLE		800,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	6,440	800,000	SH		SOLE		800,000	0	0
AGILENT TECHNOLOGIES INC	COM	00846U101	14,693	182,800	SH		SOLE		182,800	0	0
AGIOS PHARMACEUTICALS INC	COM	00847X104	7,924	117,500	SH		SOLE		117,500	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	21,294	1,560,000	SH		SOLE		1,560,000	0	0
ALDER BIOPHARMACEUTICALS INC	NOTE 2.500% 2/0	014339AA3	4,798	5,000,000	PRN		SOLE		5,000,000	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	32,781	242,500	SH		SOLE		242,500	0	0
ALIGN TECHNOLOGY INC	COM	016255101	29,855	105,000	SH		SOLE		105,000	0	0
ALLAKOS INC	COM	01671P100	16,362	404,000	SH		SOLE		404,000	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	21,821	233,500	SH		SOLE		233,500	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	93,939	4,525,000	SH		SOLE		4,525,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	13,600	1,000,000	SH		SOLE		1,000,000	0	0
ANAPTYSBIO INC	COM	032724106	12,419	170,000	SH		SOLE		170,000	0	0
ANTHEM INC	COM	036752103	5,740	20,000	SH		SOLE		20,000	0	0
ARDELYX INC	COM	039697107	5,600	2,000,000	SH		SOLE		2,000,000	0	0
ARGENX SE	SPONSORED ADR	04016X101	22,683	181,700	SH		SOLE		181,700	0	0
ARVINAS INC	COM	04335A105	2,214	150,000	SH		SOLE		150,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	25,129	213,500	SH		SOLE		213,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	8,861	450,000	SH		SOLE		450,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	20,388	522,500	SH		SOLE		522,500	0	0
AXOGEN INC	COM	05463X106	12,720	603,970	SH		SOLE		603,970	0	0
AXONICS MODULATION TECH INC	COM	05465P101	9,580	400,000	SH		SOLE		400,000	0	0
BAXTER INTL INC	COM	071813109	24,450	300,700	SH		SOLE		300,700	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	28,354	214,800	SH		SOLE		214,800	0	0
BIOCRYST PHARMACEUTICALS	COM	09058V103	5,698	700,000	SH		SOLE		700,000	0	0
BIOGEN INC	COM	09062X103	23,047	97,500	SH	Call	SOLE		97,500	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	13,382	260,000	SH		SOLE		260,000	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	11,992	135,000	SH		SOLE		135,000	0	0
BLUEBIRD BIO INC	COM	09609G100	7,080	45,000	SH		SOLE		45,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	22,014	275,000	SH		SOLE		275,000	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	37,229	970,000	SH		SOLE		970,000	0	0
CELGENE CORP	COM	151020104	17,467	185,150	SH		SOLE		185,150	0	0
CHIASMA INC	COM	16706W102	3,380	650,000	SH		SOLE		650,000	0	0
CIGNA CORP NEW	COM	125523100	14,474	90,000	SH		SOLE		90,000	0	0
CLEMENTIA PHARMACEUTICALS IN	COM	185575107	7,178	275,000	SH		SOLE		275,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	6,354	256,000	SH		SOLE		256,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	9,139	670,000	SH		SOLE		670,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	23,889	1,577,893	SH		SOLE		1,577,893	0	0
COMPUGEN LTD	ORD	M25722105	4,554	1,100,000	SH		SOLE		1,100,000	0	0
CORREVIO PHARMA CORP	COM	22026V105	3,792	1,200,000	SH		SOLE		1,200,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	1,608	400,000	SH		SOLE		400,000	0	0
COVETRUS INC	COM	22304C100	20,703	650,000	SH		SOLE		650,000	0	0
CYMABAY THERAPEUTICS INC	COM	23257D103	9,495	715,000	SH		SOLE		715,000	0	0
DERMIRA INC	COM	24983L104	10,501	775,000	SH		SOLE		775,000	0	0
DERMIRA INC	NOTE 3.000% 5/1	24983LAB0	888	1,000,000	PRN		SOLE		1,000,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	2,778	380,000	SH		SOLE		380,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	35,109	183,500	SH		SOLE		183,500	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	46,720	800,000	SH		SOLE		800,000	0	0
EPIZYME INC	COM	29428V104	21,724	1,753,375	SH		SOLE		1,753,375	0	0
EXACT SCIENCES CORP	COM	30063P105	34,388	397,000	SH		SOLE		397,000	0	0
FIBROGEN INC	COM	31572Q808	16,631	306,000	SH		SOLE		306,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	6,767	505,000	SH		SOLE		505,000	0	0
FRESHPET INC	COM	358039105	9,938	235,000	SH		SOLE		235,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	19,434	165,000	SH		SOLE		165,000	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	12,968	245,000	SH		SOLE		245,000	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	6,494	925,000	SH		SOLE		925,000	0	0
GUARDANT HEALTH INC	COM	40131M109	13,806	180,000	SH		SOLE		180,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	117,999	700,000	SH		SOLE		700,000	0	0
HCA HEALTHCARE INC	COM	40412C101	59,323	455,000	SH		SOLE		455,000	0	0
HERON THERAPEUTICS INC	COM	427746102	8,554	350,000	SH		SOLE		350,000	0	0
HOMOLOGY MEDICINES INC	COM	438083107	10,260	370,000	SH		SOLE		370,000	0	0
IDEXX LABS INC	COM	45168D104	26,877	120,200	SH		SOLE		120,200	0	0
IMMUNOMEDICS INC	COM	452907108	15,368	800,000	SH		SOLE		800,000	0	0
INCYTE CORP	COM	45337C102	26,861	312,300	SH		SOLE		312,300	0	0
INFLARX NV	COM	N44821101	8,503	225,000	SH		SOLE		225,000	0	0
INSMED INC	COM PAR $.01	457669307	24,710	850,000	SH		SOLE		850,000	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	6,082	6,000,000	PRN		SOLE		6,000,000	0	0
INTERSECT ENT INC	COM	46071F103	14,950	465,000	SH		SOLE		465,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	87,013	152,500	SH		SOLE		152,500	0	0
INVITAE CORP	COM	46185L103	26,933	1,150,000	SH		SOLE		1,150,000	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	37,451	499,615	SH		SOLE		499,615	0	0
KALEIDO BIOSCIENCES INC	COM	483347100	1,451	100,050	SH		SOLE		100,050	0	0
LA JOLLA PHARMACEUTICAL CO	COM PAR $.0001 2	503459604	1,783	277,236	SH		SOLE		277,236	0	0
MACROGENICS INC	COM	556099109	5,394	300,000	SH		SOLE		300,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	31,973	255,250	SH		SOLE		255,250	0	0
MEDICINES CO	COM	584688105	20,387	729,400	SH		SOLE		729,400	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	3,013	3,000,000	PRN		SOLE		3,000,000	0	0
MEDICINES CO	NOTE 2.750% 7/1	584688AG0	4,231	5,000,000	PRN		SOLE		5,000,000	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	7,364	1,400,000	SH		SOLE		1,400,000	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	13,194	180,000	SH		SOLE		180,000	0	0
MOLINA HEALTHCARE INC	COM	60855R100	29,457	207,500	SH		SOLE		207,500	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	5,812	400,000	SH		SOLE		400,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	8,295	347,500	SH		SOLE		347,500	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	3,904	1,600,000	SH		SOLE		1,600,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	74,400	844,500	SH		SOLE		844,500	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,354	1,000,000	PRN		SOLE		1,000,000	0	0
NEVRO CORP	COM	64157F103	2,169	34,700	SH		SOLE		34,700	0	0
NOVAVAX INC	COM	670002104	1,790	3,250,000	SH		SOLE		3,250,000	0	0
NOVOCURE LTD	ORD SHS	G6674U108	9,393	195,000	SH		SOLE		195,000	0	0
OBSEVA SA	COM	H5861P103	14,325	1,120,000	SH		SOLE		1,120,000	0	0
ODONATE THERAPEUTICS INC	COM	676079106	9,839	445,000	SH		SOLE		445,000	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	47,575	1,250,000	SH		SOLE		1,250,000	0	0
PACIRA PHARMACEUTICALS INC	NOTE 2.375% 4/0	695127AD2	987	1,000,000	PRN		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	2,412	450,000	SH		SOLE		450,000	0	0
PENUMBRA INC	COM	70975L107	33,077	225,000	SH		SOLE		225,000	0	0
PHASEBIO PHARMACEUTICALS INC	COM	717224109	10,841	1,140,000	SH		SOLE		1,140,000	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	30,363	875,000	SH		SOLE		875,000	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	26,470	240,000	SH		SOLE		240,000	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	504	400,000	SH		SOLE		400,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	17,766	458,000	SH		SOLE		458,000	0	0
RA PHARMACEUTICALS INC	COM	74933V108	18,010	804,000	SH		SOLE		804,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	23,430	1,175,000	SH		SOLE		1,175,000	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,249	1,500,000	PRN		SOLE		1,500,000	0	0
RESTORBIO INC	COM	76133L103	2,728	400,000	SH		SOLE		400,000	0	0
RETROPHIN INC	COM	761299106	18,783	830,000	SH		SOLE		830,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	5,934	216,500	SH		SOLE		216,500	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	10,794	4,200,000	SH		SOLE		4,200,000	0	0
RTI SURGICAL HOLDINGS INC	COM	74975N105	11,720	1,950,000	SH		SOLE		1,950,000	0	0
SAGE THERAPEUTICS INC	COM	78667J108	14,712	92,500	SH		SOLE		92,500	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	39,869	334,500	SH		SOLE		334,500	0	0
SEATTLE GENETICS INC	COM	812578102	17,724	242,000	SH		SOLE		242,000	0	0
SOLID BIOSCIENCES INC	COM	83422E105	552	60,000	SH		SOLE		60,000	0	0
SPARK THERAPEUTICS INC	COM	84652J103	61,211	537,500	SH		SOLE		537,500	0	0
SPERO THERAPEUTICS INC	COM	84833T103	6,725	525,000	SH		SOLE		525,000	0	0
STRYKER CORP	COM	863667101	35,356	179,000	SH		SOLE		179,000	0	0
TELEFLEX INC	COM	879369106	39,281	130,000	SH		SOLE		130,000	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,457	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	12,469	550,000	SH		SOLE		550,000	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	22,171	81,000	SH		SOLE		81,000	0	0
TRANSLATE BIO INC	COM	89374L104	10,284	1,009,179	SH		SOLE		1,009,179	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	40,229	580,000	SH		SOLE		580,000	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	146,131	591,000	SH		SOLE		591,000	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	37,342	203,000	SH		SOLE		203,000	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	86,320	320,000	SH		SOLE		320,000	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	13,775	125,000	SH		SOLE		125,000	0	0
WRIGHT MED GROUP N V	ORD SHS	N96617118	28,953	920,608	SH		SOLE		920,608	0	0
ZAI LAB LTD	ADR	98887Q104	12,199	413,400	SH		SOLE		413,400	0	0
ZOGENIX INC	COM NEW	98978L204	12,927	235,000	SH		SOLE		235,000	0	0