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	9,476	76,000	SH		SOLE		76,000	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	22,405	760,000	SH		SOLE		760,000	0	0
ACADIA PHARMACEUTICALS INC	COM	004225108	64,895	1,573,200	SH		SOLE		1,573,200	0	0
ACCOLADE INC	COM	00437E102	12,633	325,000	SH		SOLE		325,000	0	0
ACELRX PHARMACEUTICALS INC	COM	00444T100	5,358	3,773,585	SH		SOLE		3,773,585	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	5,336	2,076,307	SH		SOLE		2,076,307	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	15,856	1,986,910	SH		SOLE		1,986,910	0	0
ADAPTIVE BIOTECHNOLOGIES COR	COM	00650F109	30,880	635,000	SH		SOLE		635,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	11,277	1,590,528	SH		SOLE		1,590,528	0	0
AGIOS PHARMACEUTICALS INC	COM	00847X104	55,353	1,581,509	SH		SOLE		1,581,509	0	0
AKERO THERAPEUTICS INC	COM	00973Y108	13,025	423,040	SH		SOLE		423,040	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	25,747	225,000	SH		SOLE		225,000	0	0
ALIGN TECHNOLOGY INC	COM	016255101	46,812	143,000	SH		SOLE		143,000	0	0
ALLAKOS INC	COM	01671P100	19,677	241,582	SH		SOLE		241,582	0	0
ALNYLAM PHARMACEUTICALS INC	COM	02043Q107	49,477	339,814	SH		SOLE		339,814	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	18,314	4,350,000	SH		SOLE		4,350,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	14,456	1,023,821	SH		SOLE		1,023,821	0	0
ANAPTYSBIO INC	COM	032724106	4,559	309,113	SH		SOLE		309,113	0	0
ANNEXON INC	COM	03589W102	7,159	236,811	SH		SOLE		236,811	0	0
APPLIED THERAPEUTICS INC	COM	03828A101	20,585	991,573	SH		SOLE		991,573	0	0
APREA THERAPEUTICS INC	COM	03836J102	12,470	518,290	SH		SOLE		518,290	0	0
ARDELYX INC	COM	039697107	26,654	5,076,867	SH		SOLE		5,076,867	0	0
ARGENX SE	SPONSORED ADR	04016X101	75,475	287,500	SH		SOLE		287,500	0	0
ARVINAS INC	COM	04335A105	11,367	481,468	SH		SOLE		481,468	0	0
ASCENDIS PHARMA A/S	SPONSORED ADR	04351P101	36,034	233,500	SH		SOLE		233,500	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	24,067	1,463,915	SH		SOLE		1,463,915	0	0
ATHIRA PHARMA INC	COM	04746L104	20,356	1,102,702	SH		SOLE		1,102,702	0	0
ATRECA INC	CL A COM	04965G109	6,298	450,830	SH		SOLE		450,830	0	0
AURINIA PHARMACEUTICALS INC	COM	05156V102	11,380	772,569	SH		SOLE		772,569	0	0
BAXTER INTL INC	COM	071813109	51,871	645,000	SH		SOLE		645,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	61,585	215,000	SH		SOLE		215,000	0	0
BIOGEN INC	COM	09062X103	48,935	172,500	SH		SOLE		172,500	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	26,628	350,000	SH		SOLE		350,000	0	0
BLUEPRINT MEDICINES CORP	COM	09627Y109	88,322	952,773	SH		SOLE		952,773	0	0
BOSTON SCIENTIFIC CORP	COM	101137107	42,031	1,100,000	SH		SOLE		1,100,000	0	0
BRIGHT HORIZONS FAM SOL IN D	COM	109194100	25,163	165,500	SH		SOLE		165,500	0	0
BRISTOL-MYERS SQUIBB CO	RIGHT 99/99/9999	110122157	417	185,150	SH		SOLE		185,150	0	0
CENTENE CORP DEL	COM	15135B101	76,996	1,320,000	SH		SOLE		1,320,000	0	0
CHIASMA INC	COM	16706W102	9,220	2,144,225	SH		SOLE		2,144,225	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	30,544	1,665,449	SH		SOLE		1,665,449	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	24,464	1,175,000	SH		SOLE		1,175,000	0	0
COMPUGEN LTD	ORD	M25722105	18,408	1,132,775	SH		SOLE		1,132,775	0	0
CONMED CORP	COM	207410101	14,161	180,000	SH		SOLE		180,000	0	0
CONSTELLATION PHARMCETICLS I	COM	210373106	10,448	515,680	SH		SOLE		515,680	0	0
COVETRUS INC	COM	22304C100	29,890	1,225,000	SH		SOLE		1,225,000	0	0
CYTOKINETICS INC	COM NEW	23282W605	4,471	206,495	SH		SOLE		206,495	0	0
CYTOKINETICS INC	NOTE 4.000%11/1	23282WAA8	17,795	8,000,000	PRN		SOLE		8,000,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	7,119	1,647,920	SH		SOLE		1,647,920	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	46,455	582,000	SH		SOLE		582,000	0	0
ENCOMPASS HEALTH CORP	COM	29261A100	45,356	698,000	SH		SOLE		698,000	0	0
EPIZYME INC	COM	29428V104	30,441	2,551,659	SH		SOLE		2,551,659	0	0
EXACT SCIENCES CORP	COM	30063P105	43,227	424,000	SH		SOLE		424,000	0	0
FIBROGEN INC	COM	31572Q808	12,718	309,287	SH		SOLE		309,287	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	1,276	271,585	SH		SOLE		271,585	0	0
FRESHPET INC	COM	358039105	56,551	506,500	SH		SOLE		506,500	0	0
FUSION PHARMACEUTICALS INC	COM	36118A100	11,389	947,541	SH		SOLE		947,541	0	0
GALAPAGOS NV	SPON ADR	36315X101	24,834	175,000	SH		SOLE		175,000	0	0
GALERA THERAPEUTICS INC	COM	36338D108	5,131	567,552	SH		SOLE		567,552	0	0
GAMIDA CELL LTD	SHS	M47364100	8,369	2,016,656	SH		SOLE		2,016,656	0	0
GLOBAL CORD BLOOD CORPORATIO	SHS	G39342103	3,203	904,800	SH		SOLE		904,800	0	0
GOODRX HLDGS INC	COM CL A	38246G108	5,560	100,000	SH		SOLE		100,000	0	0
GOSSAMER BIO INC	NOTE 5.000% 6/0	38341PAA0	16,049	15,573,000	PRN		SOLE		15,573,000	0	0
GUARDANT HEALTH INC	COM	40131M109	21,238	190,000	SH		SOLE		190,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	11,603	119,188	SH		SOLE		119,188	0	0
HCA HEALTHCARE INC	COM	40412C101	62,340	500,000	SH		SOLE		500,000	0	0
HEALTH CATALYST INC	COM	42225T107	25,730	703,000	SH		SOLE		703,000	0	0
HEALTHEQUITY INC	COM	42226A107	18,498	360,100	SH		SOLE		360,100	0	0
HORIZON THERAPEUTICS PUB L	SHS	G46188101	50,492	650,000	SH		SOLE		650,000	0	0
HUMANA INC	COM	444859102	100,368	242,500	SH		SOLE		242,500	0	0
IDEXX LABS INC	COM	45168D104	49,139	125,000	SH		SOLE		125,000	0	0
IGM BIOSCIENCES INC	COM	449585108	1,459	19,762	SH		SOLE		19,762	0	0
IMARA INC	COM	45249V107	7,301	358,943	SH		SOLE		358,943	0	0
IMMUNOMEDICS INC	COM	452907108	134,985	1,587,500	SH		SOLE		1,587,500	0	0
IMMUNOVANT INC	COM	45258J102	26,127	742,449	SH		SOLE		742,449	0	0
INCYTE CORP	COM	45337C102	26,922	300,000	SH		SOLE		300,000	0	0
INOZYME PHARMA INC	COM	45790W108	23,134	879,954	SH		SOLE		879,954	0	0
INSMED INC	NOTE 1.750% 1/1	457669AA7	6,541	6,000,000	PRN		SOLE		6,000,000	0	0
INSPIRE MED SYS INC	COM	457730109	30,456	236,000	SH		SOLE		236,000	0	0
INSULET CORP	COM	45784P101	74,644	315,500	SH		SOLE		315,500	0	0
INTERSECT ENT INC	COM	46071F103	8,155	500,000	SH		SOLE		500,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	85,145	120,000	SH		SOLE		120,000	0	0
INVITAE CORP	COM	46185L103	65,804	1,517,962	SH		SOLE		1,517,962	0	0
IRHYTHM TECHNOLOGIES INC	COM	450056106	148,819	625,000	SH		SOLE		625,000	0	0
ITEOS THERAPEUTICS INC	COM	46565G104	5,592	226,681	SH		SOLE		226,681	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	8,199	57,500	SH		SOLE		57,500	0	0
KARUNA THERAPEUTICS INC	COM	48576A100	18,874	244,106	SH		SOLE		244,106	0	0
KYMERA THERAPEUTICS INC	COM	501575104	22,939	709,965	SH		SOLE		709,965	0	0
LEGEND BIOTECH CORP	SPONSORED ADS	52490G102	7,784	252,138	SH		SOLE		252,138	0	0
MACROGENICS INC	COM	556099109	6,616	262,641	SH		SOLE		262,641	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	30,189	254,268	SH		SOLE		254,268	0	0
MERSANA THERAPEUTICS INC	COM	59045L106	35,107	1,885,428	SH		SOLE		1,885,428	0	0
MIRATI THERAPEUTICS INC	COM	60468T105	57,912	348,761	SH		SOLE		348,761	0	0
MIRUM PHARMACEUTICALS INC	COM	604749101	25,583	1,327,614	SH		SOLE		1,327,614	0	0
MOMENTA PHARMACEUTICALS INC	COM	60877T100	20,992	400,000	SH		SOLE		400,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	7,204	512,711	SH		SOLE		512,711	0	0
NABRIVA THERAPEUTICS PLC	SHS	G63637105	569	1,067,664	SH		SOLE		1,067,664	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	140,922	1,465,500	SH		SOLE		1,465,500	0	0
NEUROCRINE BIOSCIENCES INC	NOTE 2.250% 5/1	64125CAD1	1,385	1,000,000	PRN		SOLE		1,000,000	0	0
NEVRO CORP	COM	64157F103	53,770	386,000	SH		SOLE		386,000	0	0
NEVRO CORP	NOTE 2.750% 4/0	64157FAC7	775	500,000	PRN		SOLE		500,000	0	0
NGM BIOPHARMACEUTICALS INC	COM	62921N105	5,735	360,454	SH		SOLE		360,454	0	0
NKARTA INC	COM	65487U108	16,259	540,873	SH		SOLE		540,873	0	0
NOVAVAX INC	COM NEW	670002401	63,461	585,705	SH		SOLE		585,705	0	0
NOVOCURE LTD	ORD SHS	G6674U108	19,479	175,000	SH		SOLE		175,000	0	0
NURIX THERAPEUTICS INC	COM	67080M103	8,990	257,514	SH		SOLE		257,514	0	0
OAK STR HEALTH INC	COM	67181A107	16,032	300,000	SH		SOLE		300,000	0	0
OBSEVA SA	COM	H5861P103	3,558	1,434,652	SH		SOLE		1,434,652	0	0
ODONATE THERAPEUTICS INC	COM	676079106	6,573	489,432	SH		SOLE		489,432	0	0
ONESPAWORLD HOLDINGS LIMITED	COM	P73684113	11,310	1,740,000	SH		SOLE		1,740,000	0	0
PACIRA BIOSCIENCES	COM	695127100	60,421	1,005,000	SH		SOLE		1,005,000	0	0
PACIRA BIOSCIENCES	NOTE 2.375% 4/0	695127AD2	1,151	1,000,000	PRN		SOLE		1,000,000	0	0
PANACEA ACQUISITION CORP	UNIT 99/99/9999	698102209	4,825	402,088	SH		SOLE		402,088	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	9,053	1,673,414	SH		SOLE		1,673,414	0	0
PASSAGE BIO INC	COM	702712100	2,701	206,036	SH		SOLE		206,036	0	0
PENUMBRA INC	COM	70975L107	30,906	159,000	SH		SOLE		159,000	0	0
PHASEBIO PHARMACEUTICALS INC	COM	717224109	4,609	1,313,174	SH		SOLE		1,313,174	0	0
PHREESIA INC	COM	71944F106	25,704	800,000	SH		SOLE		800,000	0	0
POSEIDA THERAPEUTICS INC	COM	73730P108	3,260	367,499	SH		SOLE		367,499	0	0
PPD INC	COM	69355F102	19,420	525,000	SH		SOLE		525,000	0	0
PRELUDE THERAPEUTICS INC	COM	74065P101	10,855	360,263	SH		SOLE		360,263	0	0
PROTARA THERAPEUTICS INC	COM STK	74365U107	10,832	643,622	SH		SOLE		643,622	0	0
PROTHENA CORP PLC	SHS	G72800108	10,242	1,025,207	SH		SOLE		1,025,207	0	0
RADIUS HEALTH INC	COM NEW	750469207	9,233	814,208	SH		SOLE		814,208	0	0
RADIUS HEALTH INC	NOTE 3.000% 9/0	750469AA6	1,244	1,500,000	PRN		SOLE		1,500,000	0	0
RELAY THERAPEUTICS INC	COM	75943R102	17,618	413,674	SH		SOLE		413,674	0	0
RETROPHIN INC	COM	761299106	18,908	1,024,261	SH		SOLE		1,024,261	0	0
RETROPHIN INC	NOTE 2.500% 9/1	761299AB2	2,779	3,250,000	PRN		SOLE		3,250,000	0	0
RHYTHM PHARMACEUTICALS INC	COM	76243J105	10,057	464,086	SH		SOLE		464,086	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	11,383	4,742,891	SH		SOLE		4,742,891	0	0
ROYALTY PHARMA PLC	SHS CL A	G7709Q104	20,404	485,000	SH		SOLE		485,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	48,519	345,500	SH		SOLE		345,500	0	0
SEATTLE GENETICS INC	COM	812578102	48,923	250,000	SH		SOLE		250,000	0	0
SHOCKWAVE MED INC	COM	82489T104	16,676	220,000	SH		SOLE		220,000	0	0
SPERO THERAPEUTICS INC	COM	84833T103	13,797	1,236,256	SH		SOLE		1,236,256	0	0
TELEFLEX INCORPORATED	COM	879369106	44,255	130,000	SH		SOLE		130,000	0	0
TG THERAPEUTICS INC	COM	88322Q108	18,275	682,926	SH		SOLE		682,926	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	12,183	824,018	SH		SOLE		824,018	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,320	1,500,000	PRN		SOLE		1,500,000	0	0
TRANSLATE BIO INC	COM	89374L104	8,746	642,646	SH		SOLE		642,646	0	0
TRILLIUM THERAPEUTICS INC	COM NEW	89620X506	10,955	770,918	SH		SOLE		770,918	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	47,411	576,841	SH		SOLE		576,841	0	0
UNIQURE NV	SHS	N90064101	15,227	413,433	SH		SOLE		413,433	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	126,267	405,000	SH		SOLE		405,000	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	2,449	9,000	SH		SOLE		9,000	0	0
WEST PHARMACEUTICAL SVSC INC	COM	955306105	7,835	28,500	SH		SOLE		28,500	0	0
XENON PHARMACEUTICALS INC	COM	98420N105	5,709	515,711	SH		SOLE		515,711	0	0
ZAI LAB LTD	ADR	98887Q104	68,493	823,527	SH		SOLE		823,527	0	0
ZOGENIX INC	COM NEW	98978L204	7,459	415,982	SH		SOLE		415,982	0	0