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	6,788	76,000	SH		SOLE		76,000	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	22,608	900,000	SH		SOLE		900,000	0	0
ACADIA PHARMACEUTICALS INC	COM	004225108	51,136	1,055,000	SH		SOLE		1,055,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	2,663	1,644,015	SH		SOLE		1,644,015	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	19,889	1,986,910	SH		SOLE		1,986,910	0	0
ADAPTIVE BIOTECHNOLOGIES COR	COM	00650F109	27,819	575,000	SH		SOLE		575,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	14,712	1,590,528	SH		SOLE		1,590,528	0	0
AGIOS PHARMACEUTICALS INC	COM	00847X104	63,091	1,179,720	SH		SOLE		1,179,720	0	0
AKERO THERAPEUTICS INC	COM	00973Y108	6,055	242,985	SH		SOLE		242,985	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	20,596	183,500	SH		SOLE		183,500	0	0
ALIGN TECHNOLOGY INC	COM	016255101	39,245	143,000	SH		SOLE		143,000	0	0
ALLAKOS INC	COM	01671P100	17,177	239,032	SH		SOLE		239,032	0	0
ALLOGENE THERAPEUTICS INC	COM	019770106	18,861	440,468	SH		SOLE		440,468	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	51,098	345,000	SH		SOLE		345,000	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	32,178	4,650,000	SH		SOLE		4,650,000	0	0
AMGEN INC	COM	031162100	29,718	126,000	SH		SOLE		126,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	15,334	1,016,821	SH		SOLE		1,016,821	0	0
ANAPTYSBIO INC	COM	032724106	6,852	306,713	SH		SOLE		306,713	0	0
APPLIED THERAPEUTICS INC	COM	03828A101	35,845	991,573	SH		SOLE		991,573	0	0
APREA THERAPEUTICS INC	COM	03836J102	20,099	518,290	SH		SOLE		518,290	0	0
ARDELYX INC	COM	039697107	34,705	5,015,109	SH		SOLE		5,015,109	0	0
ARGENX SE	SPONSORED ADR	04016X101	64,754	287,500	SH		SOLE		287,500	0	0
ARVINAS INC	COM	04335A105	16,148	481,468	SH		SOLE		481,468	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	31,577	213,500	SH		SOLE		213,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	34,955	1,498,915	SH		SOLE		1,498,915	0	0
BAXTER INTL INC	COM	071813109	55,535	645,000	SH		SOLE		645,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	40,506	215,000	SH		SOLE		215,000	0	0
BELLUS HEALTH INC NEW	COM NEW	07987C204	7,163	696,115	SH		SOLE		696,115	0	0
BIOGEN INC	COM	09062X103	48,159	180,000	SH		SOLE		180,000	0	0
BIOHAVEN PHARMACTL HLDG CO L	COM	G11196105	14,901	203,817	SH		SOLE		203,817	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	47,794	387,500	SH		SOLE		387,500	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	74,882	960,029	SH		SOLE		960,029	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	38,621	1,100,000	SH		SOLE		1,100,000	0	0
BRIGHT HORIZONS FAM SOL IN D	COM	109194100	11,544	98,500	SH		SOLE		98,500	0	0
BRISTOL-MYERS SQUIBB CO	RIGHT 99/99/9999	110122157	663	185,150	SH		SOLE		185,150	0	0
BURNING ROCK BIOTECH LTD	SPONSORED ADS	12233L107	5,402	200,000	SH		SOLE		200,000	0	0
CENTENE CORP DEL	COM	15135B101	83,568	1,315,000	SH		SOLE		1,315,000	0	0
CHIASMA INC	COM	16706W102	7,491	1,392,312	SH		SOLE		1,392,312	0	0
CIGNA CORP NEW	COM	125523100	30,212	161,000	SH		SOLE		161,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	36,171	2,025,275	SH		SOLE		2,025,275	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	20,563	1,175,000	SH		SOLE		1,175,000	0	0
COMPUGEN LTD	ORD	M25722105	16,978	1,130,375	SH		SOLE		1,130,375	0	0
CONMED CORP	COM	207410101	12,958	180,000	SH		SOLE		180,000	0	0
CONSTELLATION PHARMCETICLS I	COM	210373106	15,496	515,680	SH		SOLE		515,680	0	0
COVETRUS INC	COM	22304C100	14,983	837,500	SH		SOLE		837,500	0	0
CYTOKINETICS INC	COM NEW	23282W605	1,825	77,417	SH		SOLE		77,417	0	0
CYTOKINETICS INC	NOTE 4.000%11/1	23282WAA8	19,082	8,000,000	PRN		SOLE		8,000,000	0	0
DECIPHERA PHARMACEUTICALS IN	COM	24344T101	12,531	209,829	SH		SOLE		209,829	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	14,725	1,660,120	SH		SOLE		1,660,120	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	40,222	582,000	SH		SOLE		582,000	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	51,557	832,500	SH		SOLE		832,500	0	0
EPIZYME INC	COM	29428V104	33,792	2,104,084	SH		SOLE		2,104,084	0	0
EXACT SCIENCES CORP	COM	30063P105	36,863	424,000	SH		SOLE		424,000	0	0
FIBROGEN INC	COM	31572Q808	12,785	315,449	SH		SOLE		315,449	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	2,481	406,729	SH		SOLE		406,729	0	0
FRESHPET INC	COM	358039105	39,822	476,000	SH		SOLE		476,000	0	0
FUSION PHARMACEUTICALS INC	COM	36118A100	16,370	937,041	SH		SOLE		937,041	0	0
GALAPAGOS NV	SPON ADR	36315X101	34,526	175,000	SH		SOLE		175,000	0	0
GALERA THERAPEUTICS INC	COM	36338D108	4,052	567,552	SH		SOLE		567,552	0	0
GAMIDA CELL LTD	SHS	M47364100	9,216	2,016,656	SH		SOLE		2,016,656	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	18,199	288,279	SH		SOLE		288,279	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	2,868	925,000	SH		SOLE		925,000	0	0
GOSSAMER BIO INC	NOTE 5.000% 6/0	38341PAA0	15,746	15,573,000	PRN		SOLE		15,573,000	0	0
GUARDANT HEALTH INC	COM	40131M109	15,415	190,000	SH		SOLE		190,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	14,732	120,043	SH		SOLE		120,043	0	0
HCA HEALTHCARE INC	COM	40412C101	53,334	549,500	SH		SOLE		549,500	0	0
HEALTH CATALYST INC	COM	42225T107	12,397	425,000	SH		SOLE		425,000	0	0
HEALTHEQUITY INC	COM	42226A107	18,780	320,100	SH		SOLE		320,100	0	0
HOMOLOGY MEDICINES INC	COM	438083107	5,341	351,638	SH		SOLE		351,638	0	0
HUMANA INC	COM	444859102	74,060	191,000	SH		SOLE		191,000	0	0
IDEXX LABS INC	COM	45168D104	41,270	125,000	SH		SOLE		125,000	0	0
IGM BIOSCIENCES INC	COM	449585108	6,955	95,278	SH		SOLE		95,278	0	0
IMARA INC	COM	45249V107	10,078	364,733	SH		SOLE		364,733	0	0
IMMUNOMEDICS INC	COM	452907108	59,457	1,677,679	SH		SOLE		1,677,679	0	0
IMMUNOVANT INC	COM	45258J102	11,014	452,319	SH		SOLE		452,319	0	0
INARI MED INC	COM	45332Y109	3,875	80,000	SH		SOLE		80,000	0	0
INCYTE CORP	COM	45337C102	25,993	250,000	SH		SOLE		250,000	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	5,861	6,000,000	PRN		SOLE		6,000,000	0	0
INSPIRE MED SYS INC	COM	457730109	23,060	265,000	SH		SOLE		265,000	0	0
INSULET CORP	COM	45784P101	56,918	293,000	SH		SOLE		293,000	0	0
INTERSECT ENT INC	COM	46071F103	6,770	500,000	SH		SOLE		500,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	68,380	120,000	SH		SOLE		120,000	0	0
INVITAE CORP	COM	46185L103	45,772	1,511,127	SH		SOLE		1,511,127	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	75,444	651,000	SH		SOLE		651,000	0	0
JOHNSON & JOHNSON	COM	478160104	14,766	105,000	SH		SOLE		105,000	0	0
KARUNA THERAPEUTICS INC	COM	48576A100	22,661	203,312	SH		SOLE		203,312	0	0
LEGEND BIOTECH CORP	SPONSORED ADS	52490G102	8,763	205,896	SH		SOLE		205,896	0	0
MACROGENICS INC	COM	556099109	6,548	234,516	SH		SOLE		234,516	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	28,796	254,268	SH		SOLE		254,268	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	43,955	1,878,428	SH		SOLE		1,878,428	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	39,818	348,761	SH		SOLE		348,761	0	0
MIRUM PHARMACEUTICALS INC	COM	604749101	25,685	1,319,910	SH		SOLE		1,319,910	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	13,308	400,000	SH		SOLE		400,000	0	0
MYOKARDIA INC	COM	62857M105	16,688	172,716	SH		SOLE		172,716	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	10,483	508,411	SH		SOLE		508,411	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	720	1,067,664	SH		SOLE		1,067,664	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	166,713	1,366,500	SH		SOLE		1,366,500	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,673	1,000,000	PRN		SOLE		1,000,000	0	0
NEVRO CORP	COM	64157F103	46,115	386,000	SH		SOLE		386,000	0	0
NEVRO CORP	NOTE 2.750% 4/0	64157FAC7	683	500,000	PRN		SOLE		500,000	0	0
NGM BIOPHARMACEUTICALS INC	COM	62921N105	7,055	357,409	SH		SOLE		357,409	0	0
NOVAVAX INC	COM NEW	670002401	47,559	570,598	SH		SOLE		570,598	0	0
NOVOCURE LTD	ORD SHS	G6674U108	10,378	175,000	SH		SOLE		175,000	0	0
OBSEVA SA	COM	H5861P103	8,385	1,423,552	SH		SOLE		1,423,552	0	0
ODONATE THERAPEUTICS INC	COM	676079106	18,512	437,231	SH		SOLE		437,231	0	0
ONESPAWORLD HOLDINGS LIMITED	COM	P73684113	8,300	1,740,000	SH		SOLE		1,740,000	0	0
PACIRA BIOSCIENCES	COM	695127100	48,535	925,000	SH		SOLE		925,000	0	0
PACIRA BIOSCIENCES	NOTE 2.375% 4/0	695127AD2	1,094	1,000,000	PRN		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	8,640	1,655,164	SH		SOLE		1,655,164	0	0
PASSAGE BIO INC	COM	702712100	5,560	203,436	SH		SOLE		203,436	0	0
PENUMBRA INC	COM	70975L107	37,016	207,000	SH		SOLE		207,000	0	0
PHASEBIO PHARMACEUTICALS INC	COM	717224109	5,262	1,143,925	SH		SOLE		1,143,925	0	0
PHREESIA INC	COM	71944F106	18,424	651,500	SH		SOLE		651,500	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	41,488	2,306,196	SH		SOLE		2,306,196	0	0
PPD INC	COM	69355F102	13,065	487,500	SH		SOLE		487,500	0	0
PROTHENA CORP PLC	SHS	G72800108	10,347	989,218	SH		SOLE		989,218	0	0
RADIUS HEALTH INC	COM NEW	750469207	13,674	1,003,259	SH		SOLE		1,003,259	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,105	1,500,000	PRN		SOLE		1,500,000	0	0
REPARE THERAPEUTICS INC	COM	760273102	8,525	274,815	SH		SOLE		274,815	0	0
RETROPHIN INC	COM	761299106	20,905	1,024,261	SH		SOLE		1,024,261	0	0
RETROPHIN INC	NOTE 2.500% 9/1	761299AB2	2,713	3,250,000	PRN		SOLE		3,250,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	11,420	512,111	SH		SOLE		512,111	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	10,793	5,897,642	SH		SOLE		5,897,642	0	0
ROYALTY PHARMA PLC	SHS CL A	G7709Q104	24,275	500,000	SH		SOLE		500,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	55,397	345,500	SH		SOLE		345,500	0	0
SEATTLE GENETICS INC	COM	812578102	42,480	250,000	SH		SOLE		250,000	0	0
SHOCKWAVE MED INC	COM	82489T104	9,356	197,500	SH		SOLE		197,500	0	0
SPERO THERAPEUTICS INC	COM	84833T103	8,323	615,177	SH		SOLE		615,177	0	0
STAAR SURGICAL CO	COM PAR $0.01	852312305	8,000	130,000	SH		SOLE		130,000	0	0
TELEFLEX INCORPORATED	COM	879369106	47,317	130,000	SH		SOLE		130,000	0	0
TG THERAPEUTICS INC	COM	88322Q108	13,303	682,926	SH		SOLE		682,926	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,460	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	17,384	828,218	SH		SOLE		828,218	0	0
TRANSLATE BIO INC	COM	89374L104	11,850	661,268	SH		SOLE		661,268	0	0
TRILLIUM THERAPEUTICS INC	COM NEW	89620X506	6,170	762,618	SH		SOLE		762,618	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	50,596	646,841	SH		SOLE		646,841	0	0
UNIQURE NV	SHS	N90064101	18,345	407,133	SH		SOLE		407,133	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	119,455	405,000	SH		SOLE		405,000	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	36,289	125,000	SH		SOLE		125,000	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	16,129	71,000	SH		SOLE		71,000	0	0
XENON PHARMACEUTICALS INC	COM	98420N105	6,467	515,711	SH		SOLE		515,711	0	0
ZAI LAB LTD	ADR	98887Q104	66,792	813,246	SH		SOLE		813,246	0	0
ZOGENIX INC	COM NEW	98978L204	11,236	415,982	SH		SOLE		415,982	0	0