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
ABBVIE INC	COM	00287Y109	5,184	87,500	SH		SOLE		87,500	0	0
ACADIA HEALTHCARE COMPANY IN	COM	00404A109	42,161	675,000	SH		SOLE		675,000	0	0
ACHILLION PHARMACEUTICALS IN	COM	00448Q201	11,923	1,105,000	SH		SOLE		1,105,000	0	0
ACLARIS THERAPEUTICS INC	COM	00461U105	24,142	896,154	SH		SOLE		896,154	0	0
ADAPTIMMUNE THERAPEUTICS PLC	SPONDS ADR	00653A107	9,226	765,001	SH		SOLE		765,001	0	0
ADURO BIOTECH INC	COM	00739L101	11,678	415,000	SH		SOLE		415,000	0	0
ADVANCED ACCELERATOR APPLIC	SPONSORED ADS	00790T100	25,016	800,000	SH		SOLE		800,000	0	0
AETNA INC NEW	COM	00817Y108	44,437	411,000	SH		SOLE		411,000	0	0
AIMMUNE THERAPEUTICS INC	COM	00900T107	4,790	259,646	SH		SOLE		259,646	0	0
ALEXION PHARMACEUTICALS INC	COM	015351109	36,815	193,000	SH		SOLE		193,000	0	0
ALLERGAN PLC	SHS	G0177J108	50,625	162,000	SH		SOLE		162,000	0	0
ALLERGAN PLC	PFD CONV SER A	G0177J116	5,136	5,000	SH		SOLE		5,000	0	0
AMGEN INC	COM	031162100	13,132	80,900	SH		SOLE		80,900	0	0
AMICUS THERAPEUTICS INC	COM	03152W109	5,495	566,500	SH		SOLE		566,500	0	0
ANACOR PHARMACEUTICALS INC	COM	032420101	8,699	77,000	SH		SOLE		77,000	0	0
ANTHEM INC	COM	036752103	16,844	120,800	SH		SOLE		120,800	0	0
ANTHERA PHARMACEUTICALS INC	COM NEW	03674U201	1,763	380,000	SH		SOLE		380,000	0	0
ARATANA THERAPEUTICS INC	COM	03874P101	242	43,445	SH		SOLE		43,445	0	0
ARDELYX INC	COM	039697107	12,367	682,500	SH		SOLE		682,500	0	0
ASCENDIS PHARMA A S	SPONSORED ADR	04351P101	4,946	270,000	SH		SOLE		270,000	0	0
ASSEMBLY BIOSCIENCES INC	COM	045396108	2,786	371,000	SH		SOLE		371,000	0	0
ATHENAHEALTH INC	COM	04685W103	6,358	39,500	SH		SOLE		39,500	0	0
ATYR PHARMA INC	COM	002120103	4,081	415,196	SH		SOLE		415,196	0	0
BAXALTA INC	COM	07177M103	31,614	810,000	SH		SOLE		810,000	0	0
BIOGEN INC	COM	09062X103	15,517	50,650	SH		SOLE		50,650	0	0
BIOMARIN PHARMACEUTICAL INC	COM	09061G101	7,333	70,000	SH		SOLE		70,000	0	0
BLUEBIRD BIO INC	COM	09609G100	1,284	20,000	SH		SOLE		20,000	0	0
CARDIOME PHARMA CORP	COM NO PAR	14159U301	9,651	1,190,000	SH		SOLE		1,190,000	0	0
CELGENE CORP	COM	151020104	27,545	230,000	SH		SOLE		230,000	0	0
CERULEAN PHARMA INC	COM	15708Q105	1,750	625,000	SH		SOLE		625,000	0	0
CHIASMA INC	COM	16706W102	9,540	487,500	SH		SOLE		487,500	0	0
CHINA CORD BLOOD CORP	SHS	G21107100	5,606	880,000	SH		SOLE		880,000	0	0
CIDARA THERAPEUTICS INC	COM	171757107	4,290	250,000	SH		SOLE		250,000	0	0
CIGNA CORPORATION	COM	125509109	17,852	122,000	SH		SOLE		122,000	0	0
CLOVIS ONCOLOGY INC	COM	189464100	4,375	125,000	SH		SOLE		125,000	0	0
COHERUS BIOSCIENCES INC	COM	19249H103	6,475	282,000	SH		SOLE		282,000	0	0
COLLEGIUM PHARMACEUTICAL INC	COM	19459J104	27,651	1,005,487	SH		SOLE		1,005,487	0	0
COMPUGEN LTD	ORD	M25722105	5,144	805,000	SH		SOLE		805,000	0	0
COOPER COS INC	COM NEW	216648402	5,905	44,000	SH		SOLE		44,000	0	0
DBV TECHNOLOGIES S A	SPONSORED ADR	23306J101	908	25,000	SH		SOLE		25,000	0	0
DERMIRA INC	COM	24983L104	10,037	290,000	SH		SOLE		290,000	0	0
DIMENSION THERAPEUTICS INC	COM	25433V105	3,061	271,370	SH		SOLE		271,370	0	0
DYAX CORP	COM	26746E103	4,665	124,000	SH		SOLE		124,000	0	0
DYNAVAX TECHNOLOGIES CORP	COM NEW	268158201	3,624	150,000	SH		SOLE		150,000	0	0
EGALET CORP	COM	28226B104	3,306	300,000	SH		SOLE		300,000	0	0
ENDOCHOICE HLDGS INC	COM	29272U103	4,927	590,000	SH		SOLE		590,000	0	0
ENVISION HEALTHCARE HLDGS IN	COM	29413U103	6,363	245,000	SH		SOLE		245,000	0	0
EPIZYME INC	COM	29428V104	5,927	370,000	SH		SOLE		370,000	0	0
FIBROGEN INC	COM	31572Q808	5,789	190,000	SH		SOLE		190,000	0	0
FIVE PRIME THERAPEUTICS INC	COM	33830X104	5,603	135,000	SH		SOLE		135,000	0	0
GALAPAGOS NV	SPON ADR	36315X101	13,205	210,000	SH		SOLE		210,000	0	0
GENOCEA BIOSCIENCES INC	COM	372427104	2,530	480,000	SH		SOLE		480,000	0	0
GILEAD SCIENCES INC	COM	375558103	32,917	325,300	SH		SOLE		325,300	0	0
GLOBAL BLOOD THERAPEUTICS IN	COM	37890U108	2,279	70,500	SH		SOLE		70,500	0	0
GW PHARMACEUTICALS PLC	ADS	36197T103	8,055	116,000	SH		SOLE		116,000	0	0
HCA HOLDINGS INC	COM	40412C101	29,081	430,000	SH		SOLE		430,000	0	0
HEALTHSOUTH CORP	COM NEW	421924309	6,788	195,000	SH		SOLE		195,000	0	0
HEARTWARE INTL INC	COM	422368100	8,098	160,669	SH		SOLE		160,669	0	0
IDEXX LABS INC	COM	45168D104	9,297	127,500	SH		SOLE		127,500	0	0
INCYTE CORP	COM	45337C102	13,773	127,000	SH		SOLE		127,000	0	0
INFINITY PHARMACEUTICALS INC	COM	45665G303	1,688	215,000	SH		SOLE		215,000	0	0
INOVALON HLDGS INC	COM CL A	45781D101	8,114	477,300	SH		SOLE		477,300	0	0
INSMED INC	COM PAR $.01	457669307	7,850	432,500	SH		SOLE		432,500	0	0
INSYS THERAPEUTICS INC NEW	COM NEW	45824V209	9,691	338,500	SH		SOLE		338,500	0	0
INTERCEPT PHARMACEUTICALS IN	COM	45845P108	2,315	15,500	SH		SOLE		15,500	0	0
INTERSECT ENT INC	COM	46071F103	7,589	337,293	SH		SOLE		337,293	0	0
INTRA CELLULAR THERAPIES INC	COM	46116X101	9,682	180,000	SH		SOLE		180,000	0	0
INTUITIVE SURGICAL INC	COM NEW	46120E602	21,573	39,500	SH		SOLE		39,500	0	0
INVITAE CORP	COM	46185L103	5,114	622,900	SH		SOLE		622,900	0	0
JAZZ PHARMACEUTICALS PLC	SHS USD	G50871105	11,287	80,300	SH		SOLE		80,300	0	0
JUNO THERAPEUTICS INC	COM	48205A109	8,662	197,001	SH		SOLE		197,001	0	0
KITE PHARMA INC	COM	49803L109	4,930	80,000	SH		SOLE		80,000	0	0
LILLY ELI & CO	COM	532457108	23,247	275,897	SH		SOLE		275,897	0	0
MACROGENICS INC	COM	556099109	6,751	218,000	SH		SOLE		218,000	0	0
MCKESSON CORP	COM	58155Q103	14,299	72,500	SH		SOLE		72,500	0	0
MEDICINES CO	COM	584688105	23,338	625,000	SH		SOLE		625,000	0	0
MEDNAX INC	COM	58502B106	13,830	193,000	SH		SOLE		193,000	0	0
MIRNA THERAPEUTICS INC	COM	60470J103	938	150,000	SH		SOLE		150,000	0	0
NABRIVA THERAPEUTICS AG	SPONSORED ADR	62957M104	2,244	235,000	SH		SOLE		235,000	0	0
NEUROCRINE BIOSCIENCES INC	COM	64125C109	21,355	377,500	SH		SOLE		377,500	0	0
NIVALIS THERAPEUTICS INC	COM	65481J109	3,785	489,000	SH		SOLE		489,000	0	0
NOVADAQ TECHNOLOGIES INC	COM	66987G102	6,880	540,000	SH		SOLE		540,000	0	0
NOVAVAX INC	COM	670002104	6,460	770,000	SH		SOLE		770,000	0	0
NOVOCURE LTD	ORD SHS	G6674U108	4,792	214,316	SH		SOLE		214,316	0	0
OREXIGEN THERAPEUTICS INC	COM	686164104	2,838	1,650,000	SH		SOLE		1,650,000	0	0
OTONOMY INC	COM	68906L105	5,481	197,500	SH		SOLE		197,500	0	0
PACIRA PHARMACEUTICALS INC	COM	695127100	19,965	260,000	SH		SOLE		260,000	0	0
PARATEK PHARMACEUTICALS INC	COM	699374302	585	30,827	SH		SOLE		30,827	0	0
PENUMBRA INC	COM	70975L107	11,031	205,000	SH		SOLE		205,000	0	0
PERRIGO CO PLC	SHS	G97822103	4,341	30,000	SH		SOLE		30,000	0	0
PFIZER INC	COM	717081103	31,473	975,000	SH		SOLE		975,000	0	0
PORTOLA PHARMACEUTICALS INC	COM	737010108	8,489	165,000	SH		SOLE		165,000	0	0
PRA HEALTH SCIENCES INC	COM	69354M108	11,453	253,000	SH		SOLE		253,000	0	0
PROTHENA CORP PLC	SHS	G72800108	16,891	248,000	SH		SOLE		248,000	0	0
PUMA BIOTECHNOLOGY INC	COM	74587V107	862	11,000	SH		SOLE		11,000	0	0
RADIUS HEALTH INC	COM NEW	750469207	36,770	597,500	SH		SOLE		597,500	0	0
REGENERON PHARMACEUTICALS	COM	75886F107	5,972	11,000	SH		SOLE		11,000	0	0
RELYPSA INC	COM	759531106	7,142	252,000	SH		SOLE		252,000	0	0
RETROPHIN INC	COM	761299106	13,021	675,000	SH		SOLE		675,000	0	0
RIGEL PHARMACEUTICALS INC	COM NEW	766559603	3,333	1,100,000	SH		SOLE		1,100,000	0	0
RTI SURGICAL INC	COM	74975N105	7,384	1,860,000	SH		SOLE		1,860,000	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	4,147	107,500	SH		SOLE		107,500	0	0
SAREPTA THERAPEUTICS INC	COM	803607100	2,056	53,300	SH	Call	SOLE		53,300	0	0
SCYNEXIS INC	COM	811292101	3,943	635,000	SH		SOLE		635,000	0	0
SERES THERAPEUTICS INC	COM	81750R102	8,611	245,400	SH		SOLE		245,400	0	0
SOPHIRIS BIO INC	COM NEW	83578Q209	1,138	628,563	SH		SOLE		628,563	0	0
SPARK THERAPEUTICS INC	COM	84652J103	25,374	560,000	SH		SOLE		560,000	0	0
TANDEM DIABETES CARE INC	COM	875372104	6,643	562,500	SH		SOLE		562,500	0	0
TESARO INC	COM	881569107	17,475	334,000	SH		SOLE		334,000	0	0
TETRAPHASE PHARMACEUTICALS I	COM	88165N105	2,006	200,000	SH		SOLE		200,000	0	0
TEVA PHARMACEUTICAL INDS LTD	ADR	881624209	24,897	379,300	SH		SOLE		379,300	0	0
THERAPEUTICSMD INC	COM	88338N107	12,288	1,185,000	SH		SOLE		1,185,000	0	0
THERAVANCE BIOPHARMA INC	COM	G8807B106	10,572	645,000	SH		SOLE		645,000	0	0
THERMO FISHER SCIENTIFIC INC	COM	883556102	14,185	100,000	SH		SOLE		100,000	0	0
ULTRAGENYX PHARMACEUTICAL IN	COM	90400D108	11,835	105,500	SH		SOLE		105,500	0	0
VALEANT PHARMACEUTICALS INTL	COM	91911K102	8,508	83,700	SH		SOLE		83,700	0	0
VERTEX PHARMACEUTICALS INC	COM	92532F100	9,154	72,750	SH		SOLE		72,750	0	0
WELLCARE HEALTH PLANS INC	COM	94946T106	16,776	214,500	SH		SOLE		214,500	0	0
WRIGHT MED GROUP N V	ORD SHS 0.03 PAR	N96617118	11,026	456,000	SH		SOLE		456,000	0	0
XENOPORT INC	COM	98411C100	6,039	1,100,000	SH		SOLE		1,100,000	0	0