Atika Capital Management LLC — 13F Holdings & Portfolio
CIK 1599731 · latest 13F-HR filed 2026-05-14
Atika Capital Management LLC manages $796.4M in 13F-reported U.S. long-equity assets across 180 reported positions as of its 2026-03-31 13F-HR filing. Its largest disclosed positions are VRT (12.15%), VRT (6.01%), XBI (3.87%). Quarter over quarter (versus its 2025-12-31 filing) the fund opened 14 new positions, exited 26, added to 13, and trimmed 22.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
$796.4M
Long-equity book
180
Distinct positions
2026-03-31
Filed 2026-05-14
+14 / −26 / ↑13 / ↓22
vs 2025-12-31
| Name | Title / Status | Ownership | Type |
|---|
Top Adds (vs prior quarter)
- VERTIV HOLDINGS CO$63.9M +62.0%
- ECHOSTAR CORP$7.7M +57.1%
- SEAGATE TECHNOLOGY HLDNGS PL$6.7M +46.6%
- MASTEC INC$6.4M +52.3%
- CLEAN HARBORS INC$5.6M +790.8%
Top Trims
- TALEN ENERGY CORP-$9.9M -62.6%
- AMAZON COM INC-$9.4M -50.7%
- TEVA PHARMACEUTICAL INDS LTD-$8.0M -35.8%
- COGENT BIOSCIENCES INC-$6.7M -37.2%
- ELI LILLY & CO-$6.4M -14.4%
New Positions
- ORUKA THERAPEUTICS INC$11.3M
- WESTERN DIGITAL CORP$10.2M
- VANECK ETF TRUST$7.3M
- UNITED THERAPEUTICS CORP DEL$7.3M
- KARMAN HLDGS INC$7.2M
Exited Positions
- SHOPIFY INC$20.0M
- MADRIGAL PHARMACEUTICALS$19.8M
- TESLA INC$13.5M
- INSMED INC$13.4M
- DOORDASH INC$10.4M
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | VERTIV HOLDINGS CO | VRT | 92537N108 | $96.7M | 12.15% | 386,059 | SH |
| 2 | VERTIV HOLDINGS CO | VRT | 92537N108 | $47.9M | 6.01% | 191,027 | SH |
| 3 | SPDR SERIES TRUST Put | XBI | 78464A870 | $30.8M | 3.87% | 2,411 | SH |
| 4 | VERTIV HOLDINGS CO | VRT | 92537N108 | $22.3M | 2.80% | 89,014 | SH |
| 5 | ELI LILLY & CO | LLY | 532457108 | $22.0M | 2.76% | 23,931 | SH |
| 6 | VANECK ETF TRUST Put | SMH | 92189F676 | $16.1M | 2.02% | 420 | SH |
| 7 | INTUITIVE SURGICAL INC | ISRG | 46120E602 | $15.2M | 1.91% | 32,976 | SH |
| 8 | SPDR SERIES TRUST Put | XBI | 78464A870 | $14.5M | 1.82% | 1,132 | SH |
| 9 | ISHARES TR Put | IWM | 464287655 | $14.5M | 1.82% | 583 | SH |
| 10 | ECHOSTAR CORP | SATS | 278768106 | $12.4M | 1.56% | 106,083 | SH |
| 11 | SEAGATE TECHNOLOGY HLDNGS PL | STX | G7997R103 | $11.8M | 1.48% | 30,057 | SH |
| 12 | ECHOSTAR CORP Call | SATS | 278768106 | $11.0M | 1.38% | 938 | SH |
| 13 | ELI LILLY & CO | LLY | 532457108 | $10.9M | 1.37% | 11,853 | SH |
| 14 | MASTEC INC | MTZ | 576323109 | $10.8M | 1.36% | 33,650 | SH |
| 15 | NETFLIX INC. | NFLX | 64110L106 | $10.0M | 1.26% | 104,500 | SH |
| 16 | BWX TECHNOLOGIES INC | BWXT | 05605H100 | $9.9M | 1.24% | 48,195 | SH |
| 17 | CIENA CORP | CIEN | 171779309 | $9.6M | 1.20% | 24,646 | SH |
| 18 | TERNS PHARMACEUTICALS INC | TERN | 880881107 | $9.2M | 1.16% | 174,862 | SH |
| 19 | NETFLIX INC. Call | NFLX | 64110L106 | $9.0M | 1.12% | 931 | SH |
| 20 | SPDR SERIES TRUST Put | XBI | 78464A870 | $8.7M | 1.09% | 682 | SH |
| 21 | TEVA PHARMACEUTICAL INDS LTD | TEVA | 881624209 | $8.4M | 1.05% | 278,030 | SH |
| 22 | CLOUDFLARE INC | NET | 18915M107 | $7.8M | 0.98% | 37,949 | SH |
| 23 | INTUITIVE SURGICAL INC | ISRG | 46120E602 | $7.8M | 0.98% | 16,853 | SH |
| 24 | VANECK ETF TRUST Call | GDX | 92189F106 | $7.7M | 0.97% | 843 | SH |
| 25 | ALPHABET INC | GOOG | 02079K107 | $7.2M | 0.91% | 25,209 | SH |
| 26 | VANECK ETF TRUST Put | SMH | 92189F676 | $7.0M | 0.88% | 182 | SH |
| 27 | COGENT BIOSCIENCES INC | COGT | 19240Q201 | $6.6M | 0.83% | 171,179 | SH |
| 28 | ORUKA THERAPEUTICS INC | ORKA | 687604108 | $6.6M | 0.83% | 134,223 | SH |
| 29 | DIANTHUS THERAPEUTICS INC | DNTH | 252828108 | $6.3M | 0.79% | 75,197 | SH |
| 30 | ISHARES TR Put | IWM | 464287655 | $6.3M | 0.79% | 253 | SH |
| 31 | WESTERN DIGITAL CORP | WDC | 958102105 | $6.0M | 0.75% | 22,020 | SH |
| 32 | SEAGATE TECHNOLOGY HLDNGS PL | STX | G7997R103 | $5.8M | 0.73% | 14,902 | SH |
| 33 | ECHOSTAR CORP | SATS | 278768106 | $5.4M | 0.68% | 46,035 | SH |
| 34 | AMAZON COM INC | AMZN | 023135106 | $5.3M | 0.67% | 25,513 | SH |
| 35 | TTM TECHNOLOGIES INC | TTMI | 87305R109 | $5.3M | 0.66% | 54,207 | SH |
| 36 | FIVE BELOW INC | FIVE | 33829M101 | $5.3M | 0.66% | 23,050 | SH |
| 37 | CURTISS WRIGHT CORP | CW | 231561101 | $5.2M | 0.65% | 7,577 | SH |
| 38 | ECHOSTAR CORP Call | SATS | 278768106 | $4.9M | 0.61% | 418 | SH |
| 39 | ELI LILLY & CO | LLY | 532457108 | $4.9M | 0.61% | 5,316 | SH |
| 40 | GUARDANT HEALTH INC | GH | 40131M109 | $4.7M | 0.59% | 51,126 | SH |
| 41 | NETFLIX INC. | NFLX | 64110L106 | $4.7M | 0.59% | 48,990 | SH |
| 42 | CIENA CORP | CIEN | 171779309 | $4.7M | 0.59% | 12,084 | SH |
| 43 | MASTEC INC | MTZ | 576323109 | $4.7M | 0.59% | 14,545 | SH |
| 44 | MERCADOLIBRE INC | MELI | 58733R102 | $4.6M | 0.57% | 2,633 | SH |
| 45 | VANECK ETF TRUST Put | SMH | 92189F676 | $4.5M | 0.57% | 118 | SH |
| 46 | NETFLIX INC. Call | NFLX | 64110L106 | $4.4M | 0.55% | 457 | SH |
| 47 | VANECK ETF TRUST | GDX | 92189F106 | $4.3M | 0.54% | 46,630 | SH |
| 48 | UNITED THERAPEUTICS CORP DEL | UTHR | 91307C102 | $4.3M | 0.54% | 7,210 | SH |
| 49 | BWX TECHNOLOGIES INC | BWXT | 05605H100 | $4.3M | 0.53% | 20,832 | SH |
| 50 | APPFOLIO INC | APPF | 03783C100 | $4.2M | 0.53% | 26,862 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-03-31 | 2026-05-14 | $796.4M | 180 | 0001214659-26-006119 |
| 2025-12-31 | 2026-02-13 | $949.8M | 231 | 0001214659-26-001658 |
| 2025-09-30 | 2025-11-13 | $1.24B | 258 | 0001214659-25-016379 |