Q2 2026 13F · SEC CIK 1599731

Atika Capital Management LLC

Hedge fundFiled 2026-08-13 for Q2 2026. Open the filing ↗ · All SEC filings ↗

Reported 13F value: $1.0B
Reported positions: 62
Top holdings a year, 3 yrs: +24.2%
Assets under management: $887.3M

Atika Capital Management LLC is a hedge fund that reported 62 positions worth $1.0B in its Q2 2026 13F, filed 2026-08-13. Its largest holdings were Vertiv Holdings Co (VRT, 22.1%), Seagate Technology Hldngs Pl (STX, 7.6%), Advanced Micro Devices Inc (AMD, 5.5%). A portfolio copying its top holdings returned 24.2% a year over the last 3 years, against 20.4% for the S&P 500.

Atika Capital Management LLC holdings largest 50 of 62 positions.

Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.

Atika Capital Management LLC 13F holdings
Stock	% of 13F value	Q1 2026	Shares	Share change	Reported value
VRTVertiv Holdings Co	22.1%	26.3%	666,100	+0.0%	$223.0M
STXSeagate Technology Hldngs Pl	7.6%	3.3%	79,865	+49.3%	$77.1M
AMDAdvanced Micro Devices Inc	5.5%	—	95,500	—	$55.5M
LLYEli Lilly & Co	4.9%	6.0%	41,100	+0.0%	$49.3M
INTCIntel Corp	3.7%	—	264,000	—	$36.9M
ECHOEchoStar Corp	3.3%	3.4%	331,400	+82.1%	$33.6M
GHGuardant Health Inc	2.7%	1.3%	181,000	+98.9%	$27.2M
CIENCiena Corp	2.4%	2.7%	48,768	+11.7%	$23.9M
ISRGIntuitive Surgical Inc	2.3%	4.2%	57,216	+0.0%	$22.8M
VPGVishay Precision Group Inc	1.8%	—	118,000	—	$17.7M
MRVLMarvell Technology Inc	1.7%	—	58,000	—	$17.3M
RKLBRocket Lab Corp	1.7%	0.9%	169,000	+96.5%	$17.2M
WDCWestern Digital Corp Com	1.7%	1.6%	26,477	-29.8%	$16.9M
RVMDRevolution Medicines Inc	1.6%	—	88,000	—	$16.5M
ASNDAscendis Pharma A/s	1.6%	—	61,000	—	$16.3M
DNTHDianthus Therapeutics Inc	1.6%	1.7%	165,000	+28.1%	$16.1M
AXSMAxsome Therapeutics, Inc.	1.5%	—	63,000	—	$15.4M
TEVATeva Pharmaceutical Inds Ltd	1.5%	2.3%	440,000	-7.8%	$14.9M
MTZMasTec Inc	1.5%	2.9%	35,500	-38.4%	$14.8M
SNSharkninja Inc	1.3%	—	88,000	—	$13.4M
NFLXNetflix Inc.	1.3%	2.7%	180,000	+0.0%	$12.9M
CWCurtiss Wright Corp	1.2%	1.4%	16,000	+23.1%	$12.1M
KYMRKymera Therapeutics Inc	1.2%	—	104,000	—	$11.9M
SITMSitime Corp	1.1%	0.8%	15,000	+1.3%	$11.2M
TWSTTwist Bioscience Corp	1.1%	—	108,000	—	$11.1M
REALThe Realreal Inc	1.1%	0.6%	940,000	+108.4%	$11.1M
COGTCogent Biosciences Inc	1.0%	1.8%	272,000	-7.2%	$10.5M
BWXTBwx Technologies Inc	1.0%	2.7%	54,000	-34.6%	$10.5M
AMZNAmazon Com Inc	1.0%	1.4%	44,000	+0.7%	$10.5M
TBBBBbb Foods Inc	1.0%	0.5%	250,000	+162.6%	$10.4M
AXGNAxogen Inc	1.0%	—	221,000	—	$10.2M
NOKNokia Corp	1.0%	—	750,000	—	$10.0M
ORKAOruka Therapeutics Inc	0.9%	1.8%	100,000	-56.5%	$9.5M
TTMITtm Technologies Inc	0.9%	1.4%	50,000	-46.2%	$9.4M
CRLCharles Riv Labs Intl Inc	0.9%	—	38,000	—	$8.6M
ACMRACM Research, Inc.	0.8%	—	63,000	—	$8.0M
ROIVRoivant Sciences Ltd	0.8%	—	217,000	—	$7.7M
MELIMercadolibre Inc	0.8%	1.2%	4,510	+0.0%	$7.7M
APPFAppfolio Inc	0.8%	1.2%	47,500	+0.0%	$7.6M
PTGXProtagonist Therapeutics Inc	0.8%	1.0%	62,100	+0.0%	$7.6M
RDDTReddit Inc	0.7%	—	43,000	—	$7.5M
SMTCSemtech Corp	0.7%	—	46,000	—	$7.4M
FIVEFive Below Inc	0.7%	1.4%	40,000	+1.3%	$7.2M
FERGFerguson Enterprises Inc Common Stock Ne	0.7%	1.1%	29,300	+0.0%	$7.0M
24477V105Definium Therapeutics Inc	0.6%	—	122,000	—	$5.7M
IMNMImmunome Inc	0.6%	0.9%	262,900	+0.0%	$5.6M
HUTHut 8 Corp	0.5%	—	44,500	—	$5.1M
WRBYWarby Parker Inc	0.5%	0.4%	150,000	+11.1%	$4.6M
JATTJatt II Acquisition Corp	0.5%	—	400,000	—	$4.5M
PRAXPraxis Precision Medicines I	0.4%	—	12,900	—	$4.3M

What Atika Capital Management LLC bought and sold in Q2 2026, against Q1 2026.

New positions

Q1 2026's filing was too long to tell new positions apart.

Share counts compared with the Q1 2026 13F; a split also changes share counts. The latest filing lists more than 50 positions, so a position that left the top 50 may still be held.

How the holdings did against the S&P 500.

1 year: +19.9% /yr; S&P 500 +20.1%
3 years: +24.2% /yr; S&P 500 +20.4%
5 years: -1.6% /yr; S&P 500 +11.6%

A portfolio of the filer's 20 largest 13F positions, weighted by value, bought the trading day after each 13F was filed and held until the next one was: what copying this filer could have earned. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.

Reported 13F value by quarter.

13F value by quarter
Quarter	13F value	Positions
Q2 2026	$1.0B	62
Q1 2026	$633.6M	52
Q4 2025	$718.1M	64
Q3 2025	$1.2B	76
Q2 2025	$957.3M	57
Q1 2025	$651.3M	53
Q4 2024	$772.3M	73
Q3 2024	$935.1M	74
Q2 2024	$862.5M	75
Q1 2024	$891.5M	79
Q4 2023	$703.4M	69
Q3 2023	$702.0M	69

Questions about Atika Capital Management LLC's portfolio

What stocks does Atika Capital Management LLC own?

Atika Capital Management LLC's latest 13F, for Q2 2026 and filed Aug 13, 2026, lists 62 positions worth $1.0B. The largest are Vertiv Holdings Co (VRT) at 22.1%, Seagate Technology Hldngs Pl (STX) at 7.6%, Advanced Micro Devices Inc (AMD) at 5.5%, Eli Lilly & Co (LLY) at 4.9% and Intel Corp (INTC) at 3.7%.

What did Atika Capital Management LLC buy last quarter?

In Q2 2026, Atika Capital Management LLC added Bbb Foods Inc (TBBB) (+162.6% shares), The Realreal Inc (REAL) (+108.4% shares) and Guardant Health Inc (GH) (+98.9% shares), compared with its Q1 2026 filing.

What did Atika Capital Management LLC sell last quarter?

In Q2 2026, Atika Capital Management LLC cut from its top 50 Terns Pharmaceuticals Inc (TERN), cut from its top 50 Cloudflare Inc (NET), cut from its top 50 Alphabet Inc (GOOG), cut from its top 50 Vaneck ETF Trust (GDX), cut from its top 50 United Therapeutics Corp Del (UTHR), Oruka Therapeutics Inc (ORKA) (-56.5% shares), Ttm Technologies Inc (TTMI) (-46.2% shares) and MasTec Inc (MTZ) (-38.4% shares), compared with its Q1 2026 filing.

How has Atika Capital Management LLC's portfolio performed?

A portfolio copying Atika Capital Management LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned +24.2% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +19.9% against +20.1%. Over 5 years: -1.6% a year against +11.6%.

When is Atika Capital Management LLC's next 13F filing due?

13F filings are due 45 days after each quarter ends. Atika Capital Management LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.

How much money does Atika Capital Management LLC manage?

Atika Capital Management LLC reported $887.3M of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $1.0B.