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
Expires:	Oct 31, 2018
Estimated average burden
hours per response:		23.8

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	38,313	1,157,500	SH		SOLE		1,157,500	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	5,679	1,375,000	SH		SOLE		1,375,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	29,854	1,100,000	SH		SOLE		1,100,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	2,734	675,000	SH		SOLE		675,000	0	0
ADURO BIOTECH INC	COM	00739L101	4,731	415,000	SH		SOLE		415,000	0	0
ADVANCED ACCELERATOR APPLIC	SPONSORED ADS	00790T100	24,887	930,000	SH		SOLE		930,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	2,280	524,089	SH		SOLE		524,089	0	0
AETNA INC NEW	COM	00817Y108	54,688	441,000	SH		SOLE		441,000	0	0
AIMMUNE THERAPEUTICS INC	COM	00900T107	5,992	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	56,893	465,000	SH		SOLE		465,000	0	0
ALKERMES PLC	SHS	G01767105	6,948	125,000	SH		SOLE		125,000	0	0
ALLERGAN PLC	SHS	G0177J108	34,862	166,000	SH		SOLE		166,000	0	0
ALLERGAN PLC	PFD CONV SER A	G0177J116	3,820	5,000	SH		SOLE		5,000	0	0
AMARIN CORP PLC	SPONS ADR NEW	023111206	15,374	4,991,500	SH		SOLE		4,991,500	0	0
AMGEN INC	COM	031162100	14,109	96,500	SH		SOLE		96,500	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	3,765	757,500	SH		SOLE		757,500	0	0
ANTHERA PHARMACEUTICALS INC	COM NEW	03674U201	247	380,000	SH		SOLE		380,000	0	0
ARDELYX INC	COM	039697107	28,400	2,000,000	SH		SOLE		2,000,000	0	0
ARIAD PHARMACEUTICALS INC	COM	04033A100	3,110	250,000	SH		SOLE		250,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	6,578	325,000	SH		SOLE		325,000	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	4,739	390,000	SH		SOLE		390,000	0	0
ATHENAHEALTH INC	COM	04685W103	6,599	62,750	SH		SOLE		62,750	0	0
ATYR PHARMA INC	COM	002120103	1,021	475,000	SH		SOLE		475,000	0	0
AUDENTES THERAPEUTICS INC	COM	05070R104	8,861	485,000	SH		SOLE		485,000	0	0
AVEXIS INC	COM	05366U100	6,682	140,000	SH		SOLE		140,000	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	8,045	265,000	SH		SOLE		265,000	0	0
BIOGEN INC	COM	09062X103	13,328	47,000	SH		SOLE		47,000	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	10,355	125,000	SH		SOLE		125,000	0	0
BLUEBIRD BIO INC	COM	09609G100	1,758	28,500	SH		SOLE		28,500	0	0
BRISTOL MYERS SQUIBB CO	COM	110122108	26,298	450,000	SH		SOLE		450,000	0	0
CARDIOME PHARMA CORP	COM NO PAR	14159U301	3,312	1,200,000	SH		SOLE		1,200,000	0	0
CELGENE CORP	COM	151020104	28,069	242,500	SH		SOLE		242,500	0	0
CERULEAN PHARMA INC	COM	15708Q105	443	625,000	SH		SOLE		625,000	0	0
CHIASMA INC	COM	16706W102	960	492,500	SH		SOLE		492,500	0	0
CHINA CORD BLOOD CORP	SHS	G21107100	5,386	880,000	SH		SOLE		880,000	0	0
CIDARA THERAPEUTICS INC	COM	171757107	3,120	300,000	SH		SOLE		300,000	0	0
CIGNA CORPORATION	COM	125509109	33,614	252,000	SH		SOLE		252,000	0	0
CLEARSIDE BIOMEDICAL INC	COM	185063104	8,359	935,000	SH		SOLE		935,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	4,886	110,000	SH		SOLE		110,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	13,639	484,500	SH		SOLE		484,500	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	24,912	1,600,000	SH		SOLE		1,600,000	0	0
COMPUGEN LTD	ORD	M25722105	4,208	825,000	SH		SOLE		825,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	6,435	450,000	SH		SOLE		450,000	0	0
DANAHER CORP DEL	COM	235851102	12,454	160,000	SH		SOLE		160,000	0	0
DBV TECHNOLOGIES S A	SPONSORED ADR	23306J101	2,564	73,000	SH		SOLE		73,000	0	0
DERMIRA INC	COM	24983L104	10,998	362,600	SH		SOLE		362,600	0	0
DIMENSION THERAPEUTICS INC	COM	25433V105	1,180	271,370	SH		SOLE		271,370	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	652	165,000	SH		SOLE		165,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	11,291	120,500	SH		SOLE		120,500	0	0
EGALET CORP	COM	28226B104	2,295	300,000	SH		SOLE		300,000	0	0
EGALET CORP	NOTE 5.500% 4/0	28226BAB0	6,791	7,800,000	PRN		SOLE		7,800,000	0	0
ENVISION HEALTHCARE CORP	COM	29414D100	9,177	145,000	SH		SOLE		145,000	0	0
EPIZYME INC	COM	29428V104	6,897	570,000	SH		SOLE		570,000	0	0
EXACT SCIENCES CORP	COM	30063P105	6,024	450,900	SH		SOLE		450,900	0	0
EXELIXIS INC	COM	30161Q104	2,609	175,000	SH		SOLE		175,000	0	0
FIBROGEN INC	COM	31572Q808	5,136	240,000	SH		SOLE		240,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	8,218	164,000	SH		SOLE		164,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	13,480	210,000	SH		SOLE		210,000	0	0
GENOCEA BIOSCIENCES INC	COM	372427104	1,978	480,000	SH		SOLE		480,000	0	0
GILEAD SCIENCES INC	COM	375558103	19,800	276,500	SH		SOLE		276,500	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	1,394	96,500	SH		SOLE		96,500	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	39,783	356,000	SH		SOLE		356,000	0	0
HEALTHEQUITY INC	COM	42226A107	2,026	50,000	SH		SOLE		50,000	0	0
HEALTHSOUTH CORP	COM NEW	421924309	10,929	265,000	SH		SOLE		265,000	0	0
HILL ROM HLDGS INC	COM	431475102	2,667	47,500	SH		SOLE		47,500	0	0
HOLOGIC INC	COM	436440101	10,632	265,000	SH		SOLE		265,000	0	0
INCYTE CORP	COM	45337C102	16,946	169,000	SH		SOLE		169,000	0	0
INFINITY PHARMACEUTICALS INC	COM	45665G303	365	270,000	SH		SOLE		270,000	0	0
INNOVIVA INC	COM	45781M101	3,605	336,900	SH		SOLE		336,900	0	0
INSMED INC	COM PAR $.01	457669307	6,192	468,000	SH		SOLE		468,000	0	0
INTERSECT ENT INC	COM	46071F103	4,175	345,000	SH		SOLE		345,000	0	0
INTRA CELLULAR THERAPIES INC	COM	46116X101	2,867	190,000	SH		SOLE		190,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	30,440	48,000	SH		SOLE		48,000	0	0
INVITAE CORP	COM	46185L103	9,528	1,200,000	SH		SOLE		1,200,000	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	13,487	123,700	SH		SOLE		123,700	0	0
JUNO THERAPEUTICS INC	COM	48205A109	3,713	197,001	SH		SOLE		197,001	0	0
KITE PHARMA INC	COM	49803L109	3,542	79,000	SH		SOLE		79,000	0	0
LIGAND PHARMACEUTICALS INC	COM NEW	53220K504	7,113	70,000	SH		SOLE		70,000	0	0
LILLY ELI & CO	COM	532457108	23,904	325,000	SH		SOLE		325,000	0	0
MACROGENICS INC	COM	556099109	4,599	225,000	SH		SOLE		225,000	0	0
MADRIGAL PHARMACEUTICALS INC	COM	558868105	2,606	174,891	SH		SOLE		174,891	0	0
MEDICINES CO	COM	584688105	23,741	699,500	SH		SOLE		699,500	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	3,611	3,000,000	PRN		SOLE		3,000,000	0	0
MEDPACE HLDGS INC	COM	58506Q109	4,869	135,000	SH		SOLE		135,000	0	0
MERCK & CO INC	COM	58933Y105	44,153	750,000	SH		SOLE		750,000	0	0
MERUS N V	COM	N5749R100	8,444	400,000	SH		SOLE		400,000	0	0
MYOVANT SCIENCES LTD	COM	G637AM102	1,115	89,600	SH		SOLE		89,600	0	0
NABRIVA THERAPEUTICS AG	SPONSORED ADR	62957M104	3,124	525,000	SH		SOLE		525,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	15,867	410,000	SH		SOLE		410,000	0	0
NIVALIS THERAPEUTICS INC	COM	65481J109	1,095	489,000	SH		SOLE		489,000	0	0
NOVADAQ TECHNOLOGIES INC	COM	66987G102	3,935	555,000	SH		SOLE		555,000	0	0
NOVAVAX INC	COM	670002104	1,033	820,000	SH		SOLE		820,000	0	0
NOVOCURE LTD	ORD SHS	G6674U108	1,682	214,316	SH		SOLE		214,316	0	0
OREXIGEN THERAPEUTICS INC	COM NEW	686164302	288	165,300	SH		SOLE		165,300	0	0
OTONOMY INC	COM	68906L105	3,339	210,000	SH		SOLE		210,000	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	23,030	713,000	SH		SOLE		713,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	8,093	525,500	SH		SOLE		525,500	0	0
PATHEON N V	SHS	N6865W105	11,484	400,000	SH		SOLE		400,000	0	0
PENUMBRA INC	COM	70975L107	18,853	295,500	SH		SOLE		295,500	0	0
PERRIGO CO PLC	SHS	G97822103	774	9,300	SH		SOLE		9,300	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	16,536	300,000	SH		SOLE		300,000	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	5,517	450,000	SH		SOLE		450,000	0	0
PROTHENA CORP PLC	SHS	G72800108	15,224	309,500	SH		SOLE		309,500	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	2,901	94,500	SH		SOLE		94,500	0	0
RA PHARMACEUTICALS INC	COM	74933V108	12,547	826,000	SH		SOLE		826,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	34,617	910,250	SH		SOLE		910,250	0	0
REGENERON PHARMACEUTICALS	COM	75886F107	7,158	19,500	SH		SOLE		19,500	0	0
RETROPHIN INC	COM	761299106	9,881	522,000	SH		SOLE		522,000	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	2,380	1,000,000	SH		SOLE		1,000,000	0	0
RTI SURGICAL INC	COM	74975N105	6,045	1,860,000	SH		SOLE		1,860,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	5,264	191,900	SH		SOLE		191,900	0	0
SCYNEXIS INC	COM	811292101	2,424	760,000	SH		SOLE		760,000	0	0
SERES THERAPEUTICS INC	COM	81750R102	2,178	220,000	SH		SOLE		220,000	0	0
SHIRE PLC	SPONSORED ADR	82481R106	23,376	137,200	SH		SOLE		137,200	0	0
SPARK THERAPEUTICS INC	COM	84652J103	31,188	625,000	SH		SOLE		625,000	0	0
STERIS PLC	SHS USD	G84720104	4,380	65,000	SH		SOLE		65,000	0	0
TANDEM DIABETES CARE INC	COM	875372104	1,279	595,000	SH		SOLE		595,000	0	0
TESARO INC	COM	881569107	82,503	613,500	SH		SOLE		613,500	0	0
TETRAPHASE PHARMACEUTICALS I	COM	88165N105	2,813	698,000	SH		SOLE		698,000	0	0
THERAPEUTICSMD INC	COM	88338N107	9,924	1,720,000	SH		SOLE		1,720,000	0	0
THERAVANCE BIOPHARMA INC	NOTE 3.250%11/0	88339KAA0	1,713	1,500,000	PRN		SOLE		1,500,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	19,128	600,000	SH		SOLE		600,000	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	11,232	159,750	SH		SOLE		159,750	0	0
UNITEDHEALTH GROUP INC	COM	91324P102	26,407	165,000	SH		SOLE		165,000	0	0
VALEANT PHARMACEUTICALS INTL	COM	91911K102	1,037	71,400	SH		SOLE		71,400	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	6,612	89,750	SH		SOLE		89,750	0	0
WALGREENS BOOTS ALLIANCE INC	COM	931427108	13,324	161,000	SH		SOLE		161,000	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	32,145	234,500	SH		SOLE		234,500	0	0
WILLIS TOWERS WATSON PUB LTD	SHS	G96629103	13,451	110,000	SH		SOLE		110,000	0	0
WRIGHT MED GROUP INC	NOTE 2.000% 2/1	98235TAE7	1,047	1,000,000	PRN		SOLE		1,000,000	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	15,328	667,000	SH		SOLE		667,000	0	0
ZIMMER BIOMET HLDGS INC	COM	98956P102	2,178	21,100	SH		SOLE		21,100	0	0