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
10X GENOMICS INC	CL A COM	88025U109	3,200	63,500	SH		SOLE		63,500	0	0
ABBOTT LABS	COM	002824100	10,250	122,500	SH		SOLE		122,500	0	0
ABBVIE INC	COM	00287Y109	39,753	525,000	SH		SOLE		525,000	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	40,093	1,290,000	SH		SOLE		1,290,000	0	0
ACADIA PHARMACEUTICALS INC	COM	004225108	6,730	187,000	SH		SOLE		187,000	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	13,770	3,825,000	SH		SOLE		3,825,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	3,213	2,974,754	SH		SOLE		2,974,754	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	1,321	875,000	SH		SOLE		875,000	0	0
ADAPTIVE BIOTECHNOLOGIES COR	COM	00650F109	16,841	545,000	SH		SOLE		545,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	6,152	800,000	SH		SOLE		800,000	0	0
AGIOS PHARMACEUTICALS INC	COM	00847X104	11,421	352,500	SH		SOLE		352,500	0	0
AKERO THERAPEUTICS INC	COM	00973Y108	5,119	225,000	SH		SOLE		225,000	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	24,518	1,300,000	SH		SOLE		1,300,000	0	0
ALIGN TECHNOLOGY INC	COM	016255101	20,064	110,900	SH		SOLE		110,900	0	0
ALLAKOS INC	COM	01671P100	22,803	290,000	SH		SOLE		290,000	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	26,579	330,500	SH		SOLE		330,500	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	70,494	4,650,000	SH		SOLE		4,650,000	0	0
AMGEN INC	COM	031162100	24,382	126,000	SH		SOLE		126,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	8,020	1,000,000	SH		SOLE		1,000,000	0	0
ANAPTYSBIO INC	COM	032724106	8,398	240,000	SH		SOLE		240,000	0	0
ANTHEM INC	COM	036752103	6,483	27,000	SH		SOLE		27,000	0	0
ARDELYX INC	COM	039697107	14,360	3,055,261	SH		SOLE		3,055,261	0	0
ARGENX SE	SPONSORED ADR	04016X101	20,707	181,700	SH		SOLE		181,700	0	0
ARVINAS INC	COM	04335A105	3,233	150,000	SH		SOLE		150,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	20,564	213,500	SH		SOLE		213,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	12,779	1,300,000	SH		SOLE		1,300,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	11,517	410,000	SH		SOLE		410,000	0	0
AXONICS MODULATION TECH INC	COM	05465P101	5,451	202,500	SH		SOLE		202,500	0	0
BAXTER INTL INC	COM	071813109	33,676	385,000	SH		SOLE		385,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	26,304	214,800	SH		SOLE		214,800	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	14,331	343,500	SH		SOLE		343,500	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	9,605	142,500	SH		SOLE		142,500	0	0
BLUEBIRD BIO INC	COM	09609G100	4,316	47,000	SH		SOLE		47,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	24,502	333,500	SH		SOLE		333,500	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	39,469	970,000	SH		SOLE		970,000	0	0
CELGENE CORP	COM	151020104	18,385	185,150	SH		SOLE		185,150	0	0
CENTENE CORP DEL	COM	15135B101	9,941	229,800	SH		SOLE		229,800	0	0
CHIASMA INC	COM	16706W102	4,455	900,000	SH		SOLE		900,000	0	0
CIGNA CORP NEW	COM	125523100	32,923	216,900	SH		SOLE		216,900	0	0
CLOVIS ONCOLOGY INC	COM	189464100	1,006	256,000	SH		SOLE		256,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	38,089	1,880,000	SH		SOLE		1,880,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	18,114	1,577,893	SH		SOLE		1,577,893	0	0
COMPUGEN LTD	ORD	M25722105	4,653	1,100,000	SH		SOLE		1,100,000	0	0
CORREVIO PHARMA CORP	COM	22026V105	2,400	1,200,000	SH		SOLE		1,200,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	1,204	400,000	SH		SOLE		400,000	0	0
COVETRUS INC	COM	22304C100	246	20,683	SH		SOLE		20,683	0	0
CYMABAY THERAPEUTICS INC	COM	23257D103	4,608	900,000	SH		SOLE		900,000	0	0
DECIPHERA PHARMACEUTICALS IN	COM	24344T101	8,485	250,000	SH		SOLE		250,000	0	0
DERMIRA INC	COM	24983L104	4,952	775,000	SH		SOLE		775,000	0	0
DERMIRA INC	NOTE 3.000% 5/1	24983LAB0	844	1,000,000	PRN		SOLE		1,000,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	6,614	1,850,000	SH		SOLE		1,850,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	40,353	183,500	SH		SOLE		183,500	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	51,573	815,000	SH		SOLE		815,000	0	0
EPIZYME INC	COM	29428V104	19,084	1,850,100	SH		SOLE		1,850,100	0	0
EXACT SCIENCES CORP	COM	30063P105	39,017	431,750	SH		SOLE		431,750	0	0
FIBROGEN INC	COM	31572Q808	11,316	306,000	SH		SOLE		306,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	3,003	775,000	SH		SOLE		775,000	0	0
FRESHPET INC	COM	358039105	17,681	355,250	SH		SOLE		355,250	0	0
GALAPAGOS NV	SPON ADR	36315X101	26,716	175,000	SH		SOLE		175,000	0	0
GAMIDA CELL LTD	SHS	M47364100	4,330	1,000,000	SH		SOLE		1,000,000	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	12,858	265,000	SH		SOLE		265,000	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	4,477	925,000	SH		SOLE		925,000	0	0
GUARDANT HEALTH INC	COM	40131M109	12,128	190,000	SH		SOLE		190,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	10,928	95,000	SH		SOLE		95,000	0	0
HCA HEALTHCARE INC	COM	40412C101	56,296	467,500	SH		SOLE		467,500	0	0
HEALTH CATALYST INC	COM	42225T107	3,955	125,000	SH		SOLE		125,000	0	0
HOMOLOGY MEDICINES INC	COM	438083107	7,693	425,000	SH		SOLE		425,000	0	0
IDEXX LABS INC	COM	45168D104	32,686	120,200	SH		SOLE		120,200	0	0
IMMUNOMEDICS INC	COM	452907108	11,868	895,000	SH		SOLE		895,000	0	0
INCYTE CORP	COM	45337C102	23,182	312,300	SH		SOLE		312,300	0	0
INSMED INC	COM PAR $.01	457669307	15,700	890,000	SH		SOLE		890,000	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	5,031	6,000,000	PRN		SOLE		6,000,000	0	0
INSULET CORP	COM	45784P101	42,964	260,500	SH		SOLE		260,500	0	0
INTERCEPT PHARMACEUTICALS IN	COM	45845P108	3,610	54,400	SH		SOLE		54,400	0	0
INTERSECT ENT INC	COM	46071F103	14,841	872,500	SH		SOLE		872,500	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	82,339	152,500	SH		SOLE		152,500	0	0
INVITAE CORP	COM	46185L103	21,679	1,125,000	SH		SOLE		1,125,000	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	41,131	555,000	SH		SOLE		555,000	0	0
JOHNSON & JOHNSON	COM	478160104	7,245	56,000	SH		SOLE		56,000	0	0
KALEIDO BIOSCIENCES INC	COM	483347100	753	100,050	SH		SOLE		100,050	0	0
KARUNA THERAPEUTICS INC	COM	48576A100	5,882	360,400	SH		SOLE		360,400	0	0
LA JOLLA PHARMACEUTICAL CO	COM PAR $.0001 2	503459604	3,740	425,000	SH		SOLE		425,000	0	0
MACROGENICS INC	COM	556099109	3,828	300,000	SH		SOLE		300,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	23,486	272,400	SH		SOLE		272,400	0	0
MEDICINES CO	COM	584688105	40,000	800,000	SH		SOLE		800,000	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	4,521	3,000,000	PRN		SOLE		3,000,000	0	0
MEDICINES CO	NOTE 2.750% 7/1	584688AG0	6,050	5,000,000	PRN		SOLE		5,000,000	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	2,212	1,400,000	SH		SOLE		1,400,000	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	20,062	257,500	SH		SOLE		257,500	0	0
MIRUM PHARMACEUTICALS INC	COM	604749101	7,948	790,048	SH		SOLE		790,048	0	0
MOLINA HEALTHCARE INC	COM	60855R100	23,535	214,500	SH		SOLE		214,500	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	5,184	400,000	SH		SOLE		400,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	2,340	450,000	SH		SOLE		450,000	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	4,600	2,300,000	SH		SOLE		2,300,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	111,061	1,232,500	SH		SOLE		1,232,500	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,372	1,000,000	PRN		SOLE		1,000,000	0	0
NEVRO CORP	COM	64157F103	20,848	242,500	SH		SOLE		242,500	0	0
NGM BIOPHARMACEUTICALS INC	COM	62921N105	4,863	351,100	SH		SOLE		351,100	0	0
NOVAVAX INC	COM NEW	670002401	816	162,500	SH		SOLE		162,500	0	0
NOVOCURE LTD	ORD SHS	G6674U108	12,900	172,500	SH		SOLE		172,500	0	0
OBSEVA SA	COM	H5861P103	11,329	1,360,000	SH		SOLE		1,360,000	0	0
ODONATE THERAPEUTICS INC	COM	676079106	11,193	430,000	SH		SOLE		430,000	0	0
PACIRA BIOSCIENCES	COM	695127100	43,781	1,150,000	SH		SOLE		1,150,000	0	0
PACIRA BIOSCIENCES	NOTE 2.375% 4/0	695127AD2	988	1,000,000	PRN		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	1,944	450,000	SH		SOLE		450,000	0	0
PENUMBRA INC	COM	70975L107	32,614	242,500	SH		SOLE		242,500	0	0
PHASEBIO PHARMACEUTICALS INC	COM	717224109	5,908	1,416,900	SH		SOLE		1,416,900	0	0
PHREESIA INC	COM	71944F106	8,751	361,000	SH		SOLE		361,000	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	28,161	1,050,000	SH		SOLE		1,050,000	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	338	400,000	SH		SOLE		400,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	6,323	587,400	SH		SOLE		587,400	0	0
RA PHARMACEUTICALS INC	COM	74933V108	19,748	835,000	SH		SOLE		835,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	33,475	1,300,000	SH		SOLE		1,300,000	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,367	1,500,000	PRN		SOLE		1,500,000	0	0
RESTORBIO INC	COM	76133L103	3,536	400,000	SH		SOLE		400,000	0	0
RETROPHIN INC	COM	761299106	11,011	950,000	SH		SOLE		950,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	6,585	305,000	SH		SOLE		305,000	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	7,854	4,200,000	SH		SOLE		4,200,000	0	0
RTI SURGICAL HOLDINGS INC	COM	74975N105	5,558	1,950,000	SH		SOLE		1,950,000	0	0
SAGE THERAPEUTICS INC	COM	78667J108	12,977	92,500	SH		SOLE		92,500	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	25,421	337,500	SH		SOLE		337,500	0	0
SEATTLE GENETICS INC	COM	812578102	20,667	242,000	SH		SOLE		242,000	0	0
SPARK THERAPEUTICS INC	COM	84652J103	49,011	505,371	SH		SOLE		505,371	0	0
SPERO THERAPEUTICS INC	COM	84833T103	5,565	525,000	SH		SOLE		525,000	0	0
STRYKER CORP	COM	863667101	38,718	179,000	SH		SOLE		179,000	0	0
TELEFLEX INC	COM	879369106	44,168	130,000	SH		SOLE		130,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	10,714	550,000	SH		SOLE		550,000	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,376	1,500,000	PRN		SOLE		1,500,000	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	23,593	81,000	SH		SOLE		81,000	0	0
TRANSLATE BIO INC	COM	89374L104	10,158	1,025,000	SH		SOLE		1,025,000	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	26,010	608,000	SH		SOLE		608,000	0	0
UNIQURE NV	SHS	N90064101	7,656	194,500	SH		SOLE		194,500	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	128,436	591,000	SH		SOLE		591,000	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	34,392	203,000	SH		SOLE		203,000	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	83,064	320,500	SH		SOLE		320,500	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	21,628	152,500	SH		SOLE		152,500	0	0
ZAI LAB LTD	ADR	98887Q104	18,601	575,000	SH		SOLE		575,000	0	0
ZOGENIX INC	COM NEW	98978L204	10,010	250,000	SH		SOLE		250,000	0	0