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	55,590	1,275,000	SH		SOLE		1,275,000	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	6,315	1,500,000	SH		SOLE		1,500,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	20,129	675,000	SH		SOLE		675,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	4,821	875,000	SH		SOLE		875,000	0	0
ADURO BIOTECH INC	COM	00739L101	4,461	415,000	SH		SOLE		415,000	0	0
ADVANCED ACCELERATOR APPLIC	SPONSORED ADS	00790T100	33,881	850,000	SH		SOLE		850,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	3,904	524,089	SH		SOLE		524,089	0	0
AETNA INC NEW	COM	00817Y108	28,061	220,000	SH		SOLE		220,000	0	0
AIMMUNE THERAPEUTICS INC	COM	00900T107	6,367	293,000	SH		SOLE		293,000	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	3,786	182,000	SH		SOLE		182,000	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	55,395	456,900	SH		SOLE		456,900	0	0
ALKERMES PLC	SHS	G01767105	7,313	125,000	SH		SOLE		125,000	0	0
ALLERGAN PLC	SHS	G0177J108	39,661	166,000	SH		SOLE		166,000	0	0
ALLERGAN PLC	PFD CONV SER A	G0177J116	4,242	5,000	SH		SOLE		5,000	0	0
ALMOST FAMILY INC	COM	020409108	10,935	225,000	SH		SOLE		225,000	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	16,004	5,001,200	SH		SOLE		5,001,200	0	0
AMGEN INC	COM	031162100	16,079	98,000	SH		SOLE		98,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	5,401	757,500	SH		SOLE		757,500	0	0
ANTHERA PHARMACEUTICALS INC	COM NEW	03674U201	552	1,296,568	SH		SOLE		1,296,568	0	0
ARDELYX INC	COM	039697107	25,300	2,000,000	SH		SOLE		2,000,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	9,100	325,000	SH		SOLE		325,000	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	9,941	390,000	SH		SOLE		390,000	0	0
ATHENAHEALTH INC	COM	04685W103	7,071	62,750	SH		SOLE		62,750	0	0
ATYR PHARMA INC	COM	002120103	1,663	475,000	SH		SOLE		475,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	8,520	500,000	SH		SOLE		500,000	0	0
AVEXIS INC	COM	05366U100	10,644	140,000	SH		SOLE		140,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	9,702	265,000	SH		SOLE		265,000	0	0
BIOGEN INC	COM	09062X103	13,124	48,000	SH		SOLE		48,000	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	10,973	125,000	SH		SOLE		125,000	0	0
BLUEBIRD BIO INC	COM	09609G100	2,772	30,500	SH		SOLE		30,500	0	0
BRISTOL MYERS SQUIBB CO	COM	110122108	24,612	452,600	SH		SOLE		452,600	0	0
CARA THERAPEUTICS INC	COM	140755109	2,759	150,000	SH		SOLE		150,000	0	0
CARDIOME PHARMA CORP	COM NO PAR	14159U301	3,612	1,200,000	SH		SOLE		1,200,000	0	0
CELGENE CORP	COM	151020104	30,174	242,500	SH		SOLE		242,500	0	0
CERULEAN PHARMA INC	COM	15708Q105	508	625,000	SH		SOLE		625,000	0	0
CHIASMA INC	COM	16706W102	837	492,500	SH		SOLE		492,500	0	0
CHINA CORD BLOOD CORP	SHS	G21107100	5,861	880,000	SH		SOLE		880,000	0	0
CIDARA THERAPEUTICS INC	COM	171757107	2,340	300,000	SH		SOLE		300,000	0	0
CIGNA CORPORATION	COM	125509109	39,552	270,000	SH		SOLE		270,000	0	0
CLEARSIDE BIOMEDICAL INC	COM	185063104	7,424	935,000	SH		SOLE		935,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	11,747	184,500	SH		SOLE		184,500	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	14,276	675,000	SH		SOLE		675,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	17,102	1,700,000	SH		SOLE		1,700,000	0	0
COMPUGEN LTD	ORD	M25722105	3,548	825,000	SH		SOLE		825,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	8,777	422,600	SH		SOLE		422,600	0	0
DANAHER CORP DEL	COM	235851102	13,685	160,000	SH		SOLE		160,000	0	0
DBV TECHNOLOGIES S A	SPONSORED ADR	23306J101	2,571	73,000	SH		SOLE		73,000	0	0
DERMIRA INC	COM	24983L104	13,221	387,600	SH		SOLE		387,600	0	0
DIMENSION THERAPEUTICS INC	COM	25433V105	475	271,370	SH		SOLE		271,370	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	982	165,000	SH		SOLE		165,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	13,405	142,500	SH		SOLE		142,500	0	0
EGALET CORP	COM	28226B104	1,530	300,000	SH		SOLE		300,000	0	0
EGALET CORP	NOTE 5.500% 4/0	28226BAB0	6,455	7,800,000	PRN		SOLE		7,800,000	0	0
ENVISION HEALTHCARE CORP	COM	29414D100	8,891	145,000	SH		SOLE		145,000	0	0
EPIZYME INC	COM	29428V104	9,776	570,000	SH		SOLE		570,000	0	0
EXACT SCIENCES CORP	COM	30063P105	7,972	337,500	SH		SOLE		337,500	0	0
EXELIXIS INC	COM	30161Q104	3,792	175,000	SH		SOLE		175,000	0	0
FIBROGEN INC	COM	31572Q808	5,916	240,000	SH		SOLE		240,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	5,965	165,000	SH		SOLE		165,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	18,100	210,000	SH		SOLE		210,000	0	0
GENOCEA BIOSCIENCES INC	COM	372427104	2,923	480,000	SH		SOLE		480,000	0	0
GILEAD SCIENCES INC	COM	375558103	19,459	286,500	SH		SOLE		286,500	0	0
GLAUKOS CORP	COM	377322102	3,206	62,500	SH		SOLE		62,500	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	5,528	150,000	SH		SOLE		150,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	43,115	356,500	SH		SOLE		356,500	0	0
HEALTHEQUITY INC	COM	42226A107	2,123	50,000	SH		SOLE		50,000	0	0
HEALTHSOUTH CORP	COM NEW	421924309	11,345	265,000	SH		SOLE		265,000	0	0
HILL ROM HLDGS INC	COM	431475102	3,177	45,000	SH		SOLE		45,000	0	0
HOLOGIC INC	COM	436440101	14,467	340,000	SH		SOLE		340,000	0	0
HUMANA INC	COM	444859102	27,314	132,500	SH		SOLE		132,500	0	0
INCYTE CORP	COM	45337C102	22,590	169,000	SH		SOLE		169,000	0	0
INFINITY PHARMACEUTICALS INC	COM	45665G303	872	270,000	SH		SOLE		270,000	0	0
INNOVIVA INC	COM	45781M101	3,250	235,000	SH		SOLE		235,000	0	0
INSMED INC	COM PAR $.01	457669307	8,195	468,000	SH		SOLE		468,000	0	0
INTERSECT ENT INC	COM	46071F103	5,917	345,000	SH		SOLE		345,000	0	0
INTRA CELLULAR THERAPIES INC	COM	46116X101	3,088	190,000	SH		SOLE		190,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	36,791	48,000	SH		SOLE		48,000	0	0
INVITAE CORP	COM	46185L103	13,272	1,200,000	SH		SOLE		1,200,000	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	17,953	123,700	SH		SOLE		123,700	0	0
JOHNSON & JOHNSON	COM	478160104	21,796	175,000	SH		SOLE		175,000	0	0
JUNO THERAPEUTICS INC	COM	48205A109	4,371	197,001	SH		SOLE		197,001	0	0
KITE PHARMA INC	COM	49803L109	5,259	67,000	SH		SOLE		67,000	0	0
LIGAND PHARMACEUTICALS INC	COM NEW	53220K504	5,292	50,000	SH		SOLE		50,000	0	0
LILLY ELI & CO	COM	532457108	27,336	325,000	SH		SOLE		325,000	0	0
LOXO ONCOLOGY INC	COM	548862101	7,616	181,000	SH		SOLE		181,000	0	0
MACROGENICS INC	COM	556099109	4,185	225,000	SH		SOLE		225,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	3,465	225,000	SH		SOLE		225,000	0	0
MEDICINES CO	COM	584688105	34,230	700,000	SH		SOLE		700,000	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	4,744	3,000,000	PRN		SOLE		3,000,000	0	0
MERCK & CO INC	COM	58933Y105	47,655	750,000	SH		SOLE		750,000	0	0
MERUS N V	COM	N5749R100	9,379	384,548	SH		SOLE		384,548	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	1,761	150,000	SH		SOLE		150,000	0	0
NABRIVA THERAPEUTICS AG	SPONSORED ADR	62957M104	6,300	525,000	SH		SOLE		525,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	17,753	410,000	SH		SOLE		410,000	0	0
NEURODERM LTD	ORD SHS	M74231107	2,232	84,079	SH		SOLE		84,079	0	0
NEWLINK GENETICS CORP	COM	651511107	1,616	67,071	SH		SOLE		67,071	0	0
NIVALIS THERAPEUTICS INC	COM	65481J109	1,752	600,000	SH		SOLE		600,000	0	0
NOVADAQ TECHNOLOGIES INC	COM	66987G102	4,323	555,000	SH		SOLE		555,000	0	0
NOVAVAX INC	COM	670002104	1,050	820,000	SH		SOLE		820,000	0	0
NOVOCURE LTD	ORD SHS	G6674U108	1,736	214,316	SH		SOLE		214,316	0	0
OBSEVA SA	COM	H5861P103	8,730	838,634	SH		SOLE		838,634	0	0
OREXIGEN THERAPEUTICS INC	COM NEW	686164302	569	165,300	SH		SOLE		165,300	0	0
OTONOMY INC	COM	68906L105	2,573	210,000	SH		SOLE		210,000	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	45,600	1,000,000	SH		SOLE		1,000,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	10,116	525,500	SH		SOLE		525,500	0	0
PATHEON N V	SHS	N6865W105	10,536	400,000	SH		SOLE		400,000	0	0
PENUMBRA INC	COM	70975L107	25,911	310,500	SH		SOLE		310,500	0	0
PERRIGO CO PLC	SHS	G97822103	1,036	15,600	SH		SOLE		15,600	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	29,843	457,500	SH		SOLE		457,500	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	3,519	450,000	SH		SOLE		450,000	0	0
PROTHENA CORP PLC	SHS	G72800108	17,267	309,500	SH		SOLE		309,500	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	3,515	94,500	SH		SOLE		94,500	0	0
RA PHARMACEUTICALS INC	COM	74933V108	16,797	788,959	SH		SOLE		788,959	0	0
RADIUS HEALTH INC	COM NEW	750469207	35,181	910,250	SH		SOLE		910,250	0	0
REGENERON PHARMACEUTICALS	COM	75886F107	5,851	15,100	SH		SOLE		15,100	0	0
RETROPHIN INC	COM	761299106	7,384	400,000	SH		SOLE		400,000	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	3,310	1,000,000	SH		SOLE		1,000,000	0	0
RTI SURGICAL INC	COM	74975N105	7,440	1,860,000	SH		SOLE		1,860,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	5,742	194,000	SH		SOLE		194,000	0	0
SCYNEXIS INC	COM	811292101	2,098	760,000	SH		SOLE		760,000	0	0
SERES THERAPEUTICS INC	COM	81750R102	2,479	220,000	SH		SOLE		220,000	0	0
SHIRE PLC	SPONSORED ADR	82481R106	24,201	138,900	SH		SOLE		138,900	0	0
SPARK THERAPEUTICS INC	COM	84652J103	33,338	625,000	SH		SOLE		625,000	0	0
STERIS PLC	SHS USD	G84720104	4,515	65,000	SH		SOLE		65,000	0	0
TANDEM DIABETES CARE INC	COM	875372104	714	595,000	SH		SOLE		595,000	0	0
TESARO INC	COM	881569107	73,073	474,900	SH		SOLE		474,900	0	0
TETRAPHASE PHARMACEUTICALS I	COM	88165N105	6,415	698,000	SH		SOLE		698,000	0	0
THERAPEUTICSMD INC	COM	88338N107	11,520	1,600,000	SH		SOLE		1,600,000	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,899	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	22,092	600,000	SH		SOLE		600,000	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	10,828	159,750	SH		SOLE		159,750	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	27,062	165,000	SH		SOLE		165,000	0	0
VALEANT PHARMACEUTICALS INTL	COM	91911K102	732	66,400	SH		SOLE		66,400	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	9,896	90,500	SH		SOLE		90,500	0	0
WALGREENS BOOTS ALLIANCE INC	COM	931427108	13,371	161,000	SH		SOLE		161,000	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	32,879	234,500	SH		SOLE		234,500	0	0
WILLIS TOWERS WATSON PUB LTD	SHS	G96629103	14,398	110,000	SH		SOLE		110,000	0	0
WRIGHT MED GROUP INC	NOTE 2.000% 2/1	98235TAE7	1,198	1,000,000	PRN		SOLE		1,000,000	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	20,850	670,000	SH		SOLE		670,000	0	0
ZIMMER BIOMET HLDGS INC	COM	98956P102	2,577	21,100	SH		SOLE		21,100	0	0