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	23,158	900,750	SH		SOLE		900,750	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	3,697	2,325,000	SH		SOLE		2,325,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	9,824	1,329,400	SH		SOLE		1,329,400	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	4,313	750,000	SH		SOLE		750,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	4,869	650,000	SH		SOLE		650,000	0	0
AGILENT TECHNOLOGIES INC	COM	00846U101	12,332	182,800	SH		SOLE		182,800	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	15,119	1,475,000	SH		SOLE		1,475,000	0	0
ALDER BIOPHARMACEUTICALS INC	NOTE 2.500% 2/0	014339AA3	4,001	5,000,000	PRN		SOLE		5,000,000	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	23,610	242,500	SH		SOLE		242,500	0	0
ALIGN TECHNOLOGY INC	COM	016255101	21,990	105,000	SH		SOLE		105,000	0	0
ALLAKOS INC	COM	01671P100	21,117	404,000	SH		SOLE		404,000	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	14,145	194,000	SH		SOLE		194,000	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	60,918	4,476,000	SH		SOLE		4,476,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	9,580	1,000,000	SH		SOLE		1,000,000	0	0
ANAPTYSBIO INC	COM	032724106	8,675	136,000	SH		SOLE		136,000	0	0
APTINYX INC	COM	03836N103	5,045	305,000	SH		SOLE		305,000	0	0
ARDELYX INC	COM	039697107	3,580	2,000,000	SH		SOLE		2,000,000	0	0
ARGENX SE	SPONSORED ADR	04016X101	17,100	178,000	SH		SOLE		178,000	0	0
ARVINAS INC	COM	04335A105	1,928	150,000	SH		SOLE		150,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	15,255	243,500	SH		SOLE		243,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	10,179	450,000	SH		SOLE		450,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	10,660	500,000	SH		SOLE		500,000	0	0
AXOGEN INC	COM	05463X106	12,339	603,970	SH		SOLE		603,970	0	0
AXONICS MODULATION TECH INC	COM	05465P101	6,044	400,000	SH		SOLE		400,000	0	0
BAXTER INTL INC	COM	071813109	19,792	300,700	SH		SOLE		300,700	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	30,128	214,800	SH		SOLE		214,800	0	0
BIOCRYST PHARMACEUTICALS	COM	09058V103	5,649	700,000	SH		SOLE		700,000	0	0
BIOGEN INC	COM	09062X103	15,046	50,000	SH		SOLE		50,000	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	9,615	260,000	SH		SOLE		260,000	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	10,984	129,000	SH		SOLE		129,000	0	0
BLUEBIRD BIO INC	COM	09609G100	4,464	45,000	SH		SOLE		45,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	11,518	213,658	SH		SOLE		213,658	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	32,336	915,000	SH		SOLE		915,000	0	0
CELGENE CORP	COM	151020104	11,866	185,150	SH		SOLE		185,150	0	0
CHIASMA INC	COM	16706W102	1,633	525,000	SH		SOLE		525,000	0	0
CLEMENTIA PHARMACEUTICALS IN	COM	185575107	3,234	275,000	SH		SOLE		275,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	4,598	256,000	SH		SOLE		256,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	6,064	670,000	SH		SOLE		670,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	27,560	1,605,105	SH		SOLE		1,605,105	0	0
COMPUGEN LTD	ORD	M25722105	2,387	1,100,000	SH		SOLE		1,100,000	0	0
CORREVIO PHARMA CORP	COM	22026V105	2,988	1,200,000	SH		SOLE		1,200,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	1,468	400,000	SH		SOLE		400,000	0	0
CYMABAY THERAPEUTICS INC	COM	23257D103	4,829	613,604	SH		SOLE		613,604	0	0
DAVITA INC	COM	23918K108	11,074	215,200	SH		SOLE		215,200	0	0
DERMIRA INC	COM	24983L104	3,717	517,000	SH		SOLE		517,000	0	0
DERMIRA INC	NOTE 3.000% 5/1	24983LAB0	775	1,000,000	PRN		SOLE		1,000,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	3,477	380,000	SH		SOLE		380,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	28,107	183,500	SH		SOLE		183,500	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	44,733	725,000	SH		SOLE		725,000	0	0
EPIZYME INC	COM	29428V104	9,902	1,607,500	SH		SOLE		1,607,500	0	0
EXACT SCIENCES CORP	COM	30063P105	24,294	385,000	SH		SOLE		385,000	0	0
EXELIXIS INC	COM	30161Q104	12,223	621,400	SH		SOLE		621,400	0	0
FIBROGEN INC	COM	31572Q808	14,162	306,000	SH		SOLE		306,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	4,697	505,000	SH		SOLE		505,000	0	0
FRESHPET INC	COM	358039105	7,558	235,000	SH		SOLE		235,000	0	0
G1 THERAPEUTICS INC	COM	3621LQ109	1,915	100,000	SH		SOLE		100,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	16,284	177,500	SH		SOLE		177,500	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	10,057	245,000	SH		SOLE		245,000	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	5,966	925,000	SH		SOLE		925,000	0	0
GUARDANT HEALTH INC	COM	40131M109	8,119	216,000	SH		SOLE		216,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	58,385	599,500	SH		SOLE		599,500	0	0
HCA HEALTHCARE INC	COM	40412C101	56,625	455,000	SH		SOLE		455,000	0	0
HERON THERAPEUTICS INC	COM	427746102	13,619	525,000	SH		SOLE		525,000	0	0
HOMOLOGY MEDICINES INC	COM	438083107	10,062	450,000	SH		SOLE		450,000	0	0
IDEXX LABS INC	COM	45168D104	20,555	110,500	SH		SOLE		110,500	0	0
IMMUNOMEDICS INC	COM	452907108	11,131	780,000	SH		SOLE		780,000	0	0
INCYTE CORP	COM	45337C102	19,713	310,000	SH		SOLE		310,000	0	0
INFLARX NV	COM	N44821101	7,925	217,900	SH		SOLE		217,900	0	0
INOGEN INC	COM	45780L104	14,528	117,000	SH		SOLE		117,000	0	0
INSMED INC	COM PAR $.01	457669307	11,152	850,000	SH		SOLE		850,000	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	4,296	6,000,000	PRN		SOLE		6,000,000	0	0
INTERSECT ENT INC	COM	46071F103	13,104	465,000	SH		SOLE		465,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	72,796	152,000	SH		SOLE		152,000	0	0
INVITAE CORP	COM	46185L103	15,484	1,400,000	SH		SOLE		1,400,000	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	33,489	482,000	SH		SOLE		482,000	0	0
LA JOLLA PHARMACEUTICAL CO	COM PAR $.0001 2	503459604	2,614	277,236	SH		SOLE		277,236	0	0
LOXO ONCOLOGY INC	COM	548862101	33,827	241,500	SH		SOLE		241,500	0	0
MACROGENICS INC	COM	556099109	1,028	80,981	SH		SOLE		80,981	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	27,166	241,000	SH		SOLE		241,000	0	0
MEDICINES CO	COM	584688105	13,913	726,900	SH		SOLE		726,900	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	2,589	3,000,000	PRN		SOLE		3,000,000	0	0
MEDICINES CO	NOTE 2.750% 7/1	584688AG0	3,793	5,000,000	PRN		SOLE		5,000,000	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	4,080	1,000,000	SH		SOLE		1,000,000	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	6,363	150,000	SH		SOLE		150,000	0	0
MOLINA HEALTHCARE INC	COM	60855R100	39,747	342,000	SH		SOLE		342,000	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	4,416	400,000	SH		SOLE		400,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	5,702	347,500	SH		SOLE		347,500	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	2,336	1,600,000	SH		SOLE		1,600,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	56,314	788,600	SH		SOLE		788,600	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,196	1,000,000	PRN		SOLE		1,000,000	0	0
NOVAVAX INC	COM	670002104	5,980	3,250,000	SH		SOLE		3,250,000	0	0
NOVOCURE LTD	ORD SHS	G6674U108	6,529	195,000	SH		SOLE		195,000	0	0
OBSEVA SA	COM	H5861P103	14,179	1,120,000	SH		SOLE		1,120,000	0	0
ODONATE THERAPEUTICS INC	COM	676079106	6,266	445,000	SH		SOLE		445,000	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	53,775	1,250,000	SH		SOLE		1,250,000	0	0
PACIRA PHARMACEUTICALS INC	NOTE 2.375% 4/0	695127AD2	994	1,000,000	PRN		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	2,309	450,000	SH		SOLE		450,000	0	0
PENUMBRA INC	COM	70975L107	27,495	225,000	SH		SOLE		225,000	0	0
PHASEBIO PHARMACEUTICALS INC	COM	717224109	2,580	835,000	SH		SOLE		835,000	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	5,856	300,000	SH		SOLE		300,000	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	18,392	200,000	SH		SOLE		200,000	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	1,296	400,000	SH		SOLE		400,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	9,289	456,462	SH		SOLE		456,462	0	0
RA PHARMACEUTICALS INC	COM	74933V108	13,650	750,000	SH		SOLE		750,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	18,139	1,100,000	SH		SOLE		1,100,000	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,157	1,500,000	PRN		SOLE		1,500,000	0	0
RESTORBIO INC	COM	76133L103	3,448	400,000	SH		SOLE		400,000	0	0
RETROPHIN INC	COM	761299106	9,052	400,000	SH		SOLE		400,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	5,820	216,500	SH		SOLE		216,500	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	9,660	4,200,000	SH		SOLE		4,200,000	0	0
RTI SURGICAL INC	COM	74975N105	7,215	1,950,000	SH		SOLE		1,950,000	0	0
SAGE THERAPEUTICS INC	COM	78667J108	4,694	49,000	SH		SOLE		49,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	35,686	327,000	SH		SOLE		327,000	0	0
SEATTLE GENETICS INC	COM	812578102	11,474	202,500	SH		SOLE		202,500	0	0
SOLID BIOSCIENCES INC	COM	83422E105	1,581	58,999	SH		SOLE		58,999	0	0
SPARK THERAPEUTICS INC	COM	84652J103	21,038	537,500	SH		SOLE		537,500	0	0
SPERO THERAPEUTICS INC	COM	84833T103	3,229	525,000	SH		SOLE		525,000	0	0
STRYKER CORP	COM	863667101	28,058	179,000	SH		SOLE		179,000	0	0
TELEFLEX INC	COM	879369106	33,602	130,000	SH		SOLE		130,000	0	0
TESARO INC	COM	881569107	44,676	601,700	SH		SOLE		601,700	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,547	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	14,075	550,000	SH		SOLE		550,000	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	21,484	96,000	SH		SOLE		96,000	0	0
TRANSLATE BIO INC	COM	89374L104	7,569	1,009,179	SH		SOLE		1,009,179	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	18,479	425,000	SH		SOLE		425,000	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	150,244	603,100	SH		SOLE		603,100	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	33,639	203,000	SH		SOLE		203,000	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	91,957	389,500	SH		SOLE		389,500	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	15,685	160,000	SH		SOLE		160,000	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	27,220	1,000,000	SH		SOLE		1,000,000	0	0
ZAI LAB LTD	ADR	98887Q104	8,127	350,000	SH		SOLE		350,000	0	0
ZIMMER BIOMET HLDGS INC	COM	98956P102	12,187	117,500	SH		SOLE		117,500	0	0
ZOGENIX INC	COM NEW	98978L204	8,568	235,000	SH		SOLE		235,000	0	0