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	46,370	837,000	SH		SOLE		837,000	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	10,238	1,312,500	SH		SOLE		1,312,500	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	18,470	1,000,000	SH		SOLE		1,000,000	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	6,235	765,001	SH		SOLE		765,001	0	0
ADURO BIOTECH INC	COM	00739L101	4,694	415,000	SH		SOLE		415,000	0	0
ADVANCED ACCELERATOR APPLIC	SPONSORED ADS	00790T100	27,846	921,000	SH		SOLE		921,000	0	0
AEGLEA BIOTHERAPEUTICS INC	COM	00773J103	2,547	524,089	SH		SOLE		524,089	0	0
AETNA INC NEW	COM	00817Y108	53,749	440,100	SH		SOLE		440,100	0	0
AIMMUNE THERAPEUTICS INC	COM	00900T107	3,170	293,000	SH		SOLE		293,000	0	0
ALDER BIOPHARMACEUTICALS INC	COM	014339105	4,507	180,500	SH		SOLE		180,500	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	27,497	235,500	SH		SOLE		235,500	0	0
ALKERMES PLC	SHS	G01767105	8,406	194,500	SH		SOLE		194,500	0	0
ALLERGAN PLC	SHS	G0177J108	41,850	181,100	SH		SOLE		181,100	0	0
ALLERGAN PLC	PFD CONV SER A	G0177J116	4,164	5,000	SH		SOLE		5,000	0	0
AMERICAN RENAL ASSOCIATES HO	COM	029227105	7,243	250,000	SH		SOLE		250,000	0	0
AMGEN INC	COM	031162100	14,302	94,000	SH		SOLE		94,000	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	3,713	680,000	SH		SOLE		680,000	0	0
ANTHERA PHARMACEUTICALS INC	COM NEW	03674U201	1,391	450,000	SH		SOLE		450,000	0	0
ARDELYX INC	COM	039697107	11,131	1,275,000	SH		SOLE		1,275,000	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	3,981	300,000	SH		SOLE		300,000	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	2,165	390,000	SH		SOLE		390,000	0	0
ATHENAHEALTH INC	COM	04685W103	6,314	45,750	SH		SOLE		45,750	0	0
ATYR PHARMA INC	COM	002120103	1,205	433,500	SH		SOLE		433,500	0	0
AURIS MED HLDG AG	COM	H03579101	3,562	850,000	SH		SOLE		850,000	0	0
AVEXIS INC	COM	05366U100	5,428	142,758	SH		SOLE		142,758	0	0
BEIGENE LTD	SPONSORED ADR	07725L102	6,705	225,000	SH		SOLE		225,000	0	0
BIOGEN INC	COM	09062X103	13,941	57,650	SH		SOLE		57,650	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	8,791	113,000	SH		SOLE		113,000	0	0
BLUEBIRD BIO INC	COM	09609G100	866	20,000	SH		SOLE		20,000	0	0
BRISTOL MYERS SQUIBB CO	COM	110122108	14,453	196,500	SH		SOLE		196,500	0	0
CARDIOME PHARMA CORP	COM NO PAR	14159U301	6,144	1,200,000	SH		SOLE		1,200,000	0	0
CELGENE CORP	COM	151020104	25,101	254,500	SH		SOLE		254,500	0	0
CERNER CORP	COM	156782104	1,172	20,000	SH		SOLE		20,000	0	0
CERULEAN PHARMA INC	COM	15708Q105	1,325	625,000	SH		SOLE		625,000	0	0
CHIASMA INC	COM	16706W102	1,423	492,500	SH		SOLE		492,500	0	0
CHINA CORD BLOOD CORP	SHS	G21107100	5,060	880,000	SH		SOLE		880,000	0	0
CIDARA THERAPEUTICS INC	COM	171757107	2,578	250,000	SH		SOLE		250,000	0	0
CIGNA CORPORATION	COM	125509109	26,468	206,800	SH		SOLE		206,800	0	0
CLEARSIDE BIOMEDICAL INC	COM	185063104	9,487	1,353,326	SH		SOLE		1,353,326	0	0
CLOVIS ONCOLOGY INC	COM	189464100	1,715	125,000	SH		SOLE		125,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	6,756	400,000	SH		SOLE		400,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	14,398	1,215,000	SH		SOLE		1,215,000	0	0
COMPUGEN LTD	ORD	M25722105	5,314	820,000	SH		SOLE		820,000	0	0
CORSICANTO LTD	NOTE 3.500% 1/1	220480AB3	7,214	7,000,000	PRN		SOLE		7,000,000	0	0
CORVUS PHARMACEUTICALS INC	COM	221015100	6,417	450,000	SH		SOLE		450,000	0	0
DBV TECHNOLOGIES S A	SPONSORED ADR	23306J101	2,381	73,000	SH		SOLE		73,000	0	0
DERMIRA INC	COM	24983L104	10,381	354,900	SH		SOLE		354,900	0	0
DIMENSION THERAPEUTICS INC	COM	25433V105	1,628	271,370	SH		SOLE		271,370	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	2,406	165,000	SH		SOLE		165,000	0	0
EDWARDS LIFESCIENCES CORP	COM	28176E108	8,327	83,500	SH		SOLE		83,500	0	0
EGALET CORP	COM	28226B104	1,488	300,000	SH		SOLE		300,000	0	0
EGALET CORP	NOTE 5.500% 4/0	28226BAB0	5,923	7,800,000	PRN		SOLE		7,800,000	0	0
ENDOCHOICE HLDGS INC	COM	29272U103	3,479	710,000	SH		SOLE		710,000	0	0
ENVISION HEALTHCARE HLDGS IN	COM	29413U103	7,383	291,000	SH		SOLE		291,000	0	0
EPIZYME INC	COM	29428V104	6,118	597,500	SH		SOLE		597,500	0	0
FIBROGEN INC	COM	31572Q808	3,692	225,000	SH		SOLE		225,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	6,327	153,000	SH		SOLE		153,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	11,649	210,000	SH		SOLE		210,000	0	0
GENOCEA BIOSCIENCES INC	COM	372427104	1,968	480,000	SH		SOLE		480,000	0	0
GILEAD SCIENCES INC	COM	375558103	28,671	343,700	SH		SOLE		343,700	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	1,626	98,000	SH		SOLE		98,000	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	24,724	270,000	SH		SOLE		270,000	0	0
HCA HOLDINGS INC	COM	40412C101	33,114	430,000	SH		SOLE		430,000	0	0
HEALTHSOUTH CORP	COM NEW	421924309	10,287	265,000	SH		SOLE		265,000	0	0
HEARTWARE INTL INC	COM	422368100	17,960	311,000	SH		SOLE		311,000	0	0
HILL ROM HLDGS INC	COM	431475102	6,054	120,000	SH		SOLE		120,000	0	0
HOLOGIC INC	COM	436440101	7,958	230,000	SH		SOLE		230,000	0	0
INCYTE CORP	COM	45337C102	12,397	155,000	SH		SOLE		155,000	0	0
INFINITY PHARMACEUTICALS INC	COM	45665G303	359	270,000	SH		SOLE		270,000	0	0
INNOVIVA INC	COM	45781M101	3,548	336,900	SH		SOLE		336,900	0	0
INOVALON HLDGS INC	COM CL A	45781D101	1,878	104,302	SH		SOLE		104,302	0	0
INSMED INC	COM PAR $.01	457669307	4,905	497,500	SH		SOLE		497,500	0	0
INSYS THERAPEUTICS INC NEW	COM NEW	45824V209	4,730	365,500	SH		SOLE		365,500	0	0
INTERCEPT PHARMACEUTICALS IN	COM	45845P108	1,427	10,000	SH		SOLE		10,000	0	0
INTERSECT ENT INC	COM	46071F103	4,396	340,000	SH		SOLE		340,000	0	0
INTRA CELLULAR THERAPIES INC	COM	46116X101	7,376	190,000	SH		SOLE		190,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	29,102	44,000	SH		SOLE		44,000	0	0
INVITAE CORP	COM	46185L103	6,343	858,380	SH		SOLE		858,380	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	14,414	102,000	SH		SOLE		102,000	0	0
JUNO THERAPEUTICS INC	COM	48205A109	7,573	197,001	SH		SOLE		197,001	0	0
KITE PHARMA INC	COM	49803L109	4,000	80,000	SH		SOLE		80,000	0	0
LILLY ELI & CO	COM	532457108	21,735	276,000	SH		SOLE		276,000	0	0
MACROGENICS INC	COM	556099109	6,073	225,000	SH		SOLE		225,000	0	0
MCKESSON CORP	COM	58155Q103	14,540	77,900	SH		SOLE		77,900	0	0
MEDICINES CO	COM	584688105	22,885	680,500	SH		SOLE		680,500	0	0
MEDICINES CO	NOTE 2.500% 1/1	584688AE5	3,549	3,000,000	PRN		SOLE		3,000,000	0	0
MEDNAX INC	COM	58502B106	14,124	195,000	SH		SOLE		195,000	0	0
MERUS N V	COM	N5749R100	2,883	360,811	SH		SOLE		360,811	0	0
MIRNA THERAPEUTICS INC	COM	60470J103	639	150,000	SH		SOLE		150,000	0	0
NABRIVA THERAPEUTICS AG	SPONSORED ADR	62957M104	3,195	426,000	SH		SOLE		426,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	18,612	409,500	SH		SOLE		409,500	0	0
NIVALIS THERAPEUTICS INC	COM	65481J109	2,249	489,000	SH		SOLE		489,000	0	0
NOVADAQ TECHNOLOGIES INC	COM	66987G102	5,461	555,000	SH		SOLE		555,000	0	0
NOVAVAX INC	COM	670002104	6,198	852,500	SH		SOLE		852,500	0	0
NOVOCURE LTD	ORD SHS	G6674U108	2,501	214,316	SH		SOLE		214,316	0	0
OPHTHOTECH CORP	COM	683745103	7,272	142,500	SH		SOLE		142,500	0	0
OREXIGEN THERAPEUTICS INC	COM	686164104	711	1,653,000	SH		SOLE		1,653,000	0	0
OTONOMY INC	COM	68906L105	3,811	240,000	SH		SOLE		240,000	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	15,937	472,500	SH		SOLE		472,500	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	5,821	418,500	SH		SOLE		418,500	0	0
PENUMBRA INC	COM	70975L107	14,429	242,500	SH		SOLE		242,500	0	0
PERRIGO CO PLC	SHS	G97822103	3,436	37,900	SH		SOLE		37,900	0	0
PFIZER INC	COM	717081103	37,175	1,055,800	SH		SOLE		1,055,800	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	4,130	175,000	SH		SOLE		175,000	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	10,565	253,000	SH		SOLE		253,000	0	0
PROTEOSTASIS THERAPEUTICS IN	COM	74373B109	5,034	415,000	SH		SOLE		415,000	0	0
PROTHENA CORP PLC	SHS	G72800108	10,768	308,000	SH		SOLE		308,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	983	33,000	SH		SOLE		33,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	31,881	867,500	SH		SOLE		867,500	0	0
REGENERON PHARMACEUTICALS	COM	75886F107	5,937	17,000	SH		SOLE		17,000	0	0
RELYPSA INC	COM	759531106	1,388	75,000	SH		SOLE		75,000	0	0
RETROPHIN INC	COM	761299106	9,286	521,400	SH		SOLE		521,400	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	3,903	1,750,000	SH		SOLE		1,750,000	0	0
RTI SURGICAL INC	COM	74975N105	6,677	1,860,000	SH		SOLE		1,860,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	2,498	131,000	SH		SOLE		131,000	0	0
SCYNEXIS INC	COM	811292101	1,378	635,000	SH		SOLE		635,000	0	0
SERES THERAPEUTICS INC	COM	81750R102	7,611	262,000	SH		SOLE		262,000	0	0
SHIRE PLC	SPONSORED ADR	82481R106	22,097	120,042	SH		SOLE		120,042	0	0
SOPHIRIS BIO INC	COM NEW	83578Q209	1,054	490,000	SH		SOLE		490,000	0	0
SPARK THERAPEUTICS INC	COM	84652J103	31,189	610,000	SH		SOLE		610,000	0	0
STERIS PLC	SHS USD	G84720104	2,750	40,000	SH		SOLE		40,000	0	0
TANDEM DIABETES CARE INC	COM	875372104	4,486	595,000	SH		SOLE		595,000	0	0
TESARO INC	COM	881569107	40,344	480,000	SH		SOLE		480,000	0	0
TESARO INC	COM	881569107	3,362	40,000	SH	Call	SOLE		40,000	0	0
TETRAPHASE PHARMACEUTICALS I	COM	88165N105	1,828	425,000	SH		SOLE		425,000	0	0
TEVA PHARMACEUTICAL INDS LTD	ADR	881624209	19,841	395,000	SH		SOLE		395,000	0	0
THERAPEUTICSMD INC	COM	88338N107	13,388	1,575,000	SH		SOLE		1,575,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	15,883	700,000	SH		SOLE		700,000	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	14,806	100,200	SH		SOLE		100,200	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	6,921	141,500	SH		SOLE		141,500	0	0
VALEANT PHARMACEUTICALS INTL	COM	91911K102	1,331	66,100	SH		SOLE		66,100	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	7,355	85,500	SH		SOLE		85,500	0	0
WALGREENS BOOTS ALLIANCE INC	COM	931427108	13,357	160,400	SH		SOLE		160,400	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	25,157	234,500	SH		SOLE		234,500	0	0
WRIGHT MED GROUP INC	NOTE 2.000% 2/1	98235TAE7	919	1,000,000	PRN		SOLE		1,000,000	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	9,517	547,900	SH		SOLE		547,900	0	0
XENOPORT INC	COM	98411C100	8,413	1,195,000	SH		SOLE		1,195,000	0	0