Funds › Westfield Capital Management Co LP
Westfield Capital Management Co LP
13F for Q3 2026, filed Nov 12, 2026. 281 positions worth $30.6B.Managers with more than $100 million in US-listed stocks list their holdings each quarter, within 45 days of quarter end. Long positions only: no short sales or cash.
Latest report
Q3 2026
filed Nov 12, 2026
Reported value
$30.6B
−$49.8M (0.2%) vs Q2 2026
Positions
281
278 in Q2 2026
Top 10 share
28.6%
of reported value
CheckedEach line's price per share is checked against other managers' reports of the same stock. Unit mix-ups are corrected. Reports no fix can rescue are left out.
Clean
prices match other managers' reports
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Holdings, Q3 2026
Largest first. Common shares only; puts and calls are under All positions.
| # | The fund's own figures at the end of the quarter. A report can be up to 45 days old when it is filed. Options and bonds are not counted here. | Filing | ||||
|---|---|---|---|---|---|---|
| 1 | NVDA NVIDIA Corporation | 8.09M | $1.8B | 6.0% | +0.1% | 13F ↗ |
| 2 | GOOGL Alphabet Inc. Class A | 3.94M | $1.4B | 4.4% | +5.1% | 13F ↗ |
| 3 | ASND Ascendis Pharma A/S | 5.13M | $1.2B | 3.8% | +6.8% | 13F ↗ |
| 4 | AAPL Apple Inc. | 2.34M | $780.5M | 2.6% | -8.9% | 13F ↗ |
| 5 | AXON Axon Enterprise, Inc. | 1.61M | $680.9M | 2.2% | +8.0% | 13F ↗ |
| 6 | MSFT Microsoft Corporation | 1.32M | $678.9M | 2.2% | -6.4% | 13F ↗ |
| 7 | META Meta Platforms, Inc. | 831,946 | $603.3M | 2.0% | +22.8% | 13F ↗ |
| 8 | SNOW Snowflake Inc. | 1.74M | $589.1M | 1.9% | -0.1% | 13F ↗ |
| 9 | AVGO Broadcom Inc. | 1.62M | $570.6M | 1.9% | +4.4% | 13F ↗ |
| 10 | LLY Eli Lilly and Company | 398,729 | $461.4M | 1.5% | -4.3% | 13F ↗ |
| 11 | HWM Howmet Aerospace Inc. | 1.99M | $449.1M | 1.5% | +3.3% | 13F ↗ |
| 12 | MU Micron Technology, Inc. | 385,858 | $411.0M | 1.3% | +69.1% | 13F ↗ |
| 13 | V Visa Inc. | 1.07M | $385.1M | 1.3% | +40.6% | 13F ↗ |
| 14 | NOW ServiceNow, Inc. | 2.36M | $316.4M | 1.0% | -0.5% | 13F ↗ |
| 15 | NET Cloudflare, Inc. | 867,907 | $301.4M | 1.0% | +3.9% | 13F ↗ |
| 16 | IOT Samsara Inc. | 7.52M | $286.6M | 0.9% | +28.8% | 13F ↗ |
| 17 | LPLA LPL Financial Holdings Inc. | 894,962 | $273.7M | 0.9% | +12.8% | 13F ↗ |
| 18 | MKSI MKS Inc. | 1.03M | $273.2M | 0.9% | +10.9% | 13F ↗ |
| 19 | RBRK Rubrik, Inc. | 2.39M | $273.1M | 0.9% | +155% | 13F ↗ |
| 20 | DT Dynatrace, Inc. | 4.66M | $269.3M | 0.9% | +9.8% | 13F ↗ |
| 21 | LTH Life Time Group Holdings, Inc. | 6.40M | $255.2M | 0.8% | +6.7% | 13F ↗ |
| 22 | APG APi Group Corporation | 6.59M | $254.5M | 0.8% | +7.1% | 13F ↗ |
| 23 | PLTR Palantir Technologies Inc. | 1.32M | $246.9M | 0.8% | New | 13F ↗ |
| 24 | GH Guardant Health, Inc. | 1.34M | $239.2M | 0.8% | -17.4% | 13F ↗ |
| 25 | RYTM Rhythm Pharmaceuticals, Inc. | 2.48M | $236.2M | 0.8% | +12.3% | 13F ↗ |
| 26 | GEV GE Vernova Inc. | 244,536 | $232.4M | 0.8% | +1.4% | 13F ↗ |
| 27 | SN SharkNinja, Inc. | 1.29M | $232.1M | 0.8% | +27.8% | 13F ↗ |
| 28 | EAT Brinker International, Inc. | 1.19M | $229.7M | 0.8% | New | 13F ↗ |
| 29 | AMD Advanced Micro Devices, Inc. | 371,467 | $227.2M | 0.7% | -7.8% | 13F ↗ |
| 30 | AS Amer Sports, Inc. | 7.70M | $210.2M | 0.7% | +21.4% | 13F ↗ |
| 31 | ANET Arista Networks, Inc. | 1.03M | $209.1M | 0.7% | -22.0% | 13F ↗ |
| 32 | GRMN Garmin Ltd. | 714,984 | $205.1M | 0.7% | -17.0% | 13F ↗ |
| 33 | TSM Taiwan Semiconductor Manufacturing Company Ltd. | 435,769 | $198.8M | 0.7% | -14.7% | 13F ↗ |
| 34 | PANW Palo Alto Networks, Inc. | 495,259 | $196.8M | 0.6% | -24.8% | 13F ↗ |
| 35 | AMZN Amazon.com, Inc. | 788,881 | $196.5M | 0.6% | -8.2% | 13F ↗ |
| 36 | USFD US Foods Holding Corp. | 2.13M | $196.2M | 0.6% | New | 13F ↗ |
| 37 | FCFS FirstCash Holdings, Inc. | 902,006 | $190.5M | 0.6% | +30.1% | 13F ↗ |
| 38 | FPS Forgent Power Solutions, Inc. | 5.03M | $188.3M | 0.6% | +267% | 13F ↗ |
| 39 | PCVX Vaxcyte, Inc. | 3.28M | $186.6M | 0.6% | +32.6% | 13F ↗ |
| 40 | AME AMETEK, Inc. | 732,764 | $181.5M | 0.6% | +1.2% | 13F ↗ |
| 41 | PWR Quanta Services, Inc. | 279,726 | $179.7M | 0.6% | -15.6% | 13F ↗ |
| 42 | INSM Insmed Incorporated · Com Par $.01 | 1.55M | $177.2M | 0.6% | -4.7% | 13F ↗ |
| 43 | ITT ITT Inc. | 874,232 | $176.4M | 0.6% | +5.3% | 13F ↗ |
| 44 | CRS Carpenter Technology Corporation | 450,067 | $175.0M | 0.6% | +43.3% | 13F ↗ |
| 45 | PTCT PTC Therapeutics, Inc. | 2.70M | $174.9M | 0.6% | +38.0% | 13F ↗ |
| 46 | MDB MongoDB, Inc. | 491,763 | $171.4M | 0.6% | +229% | 13F ↗ |
| 47 | ARGX argenx SE · ADR | 175,886 | $168.7M | 0.6% | +208% | 13F ↗ |
| 48 | ABVX Abivax SA · ADR | 1.65M | $163.6M | 0.5% | +26.1% | 13F ↗ |
| 49 | FN Fabrinet | 380,827 | $161.6M | 0.5% | +291% | 13F ↗ |
| 50 | MCHP Microchip Technology Incorporated | 2.07M | $161.0M | 0.5% | +26.3% | 13F ↗ |
Showing the top 50 of 281 positions. Premium lists every position, plus puts and calls.
Changes since Q2 2026
44 new, 141 added to, 88 trimmed, 41 exited, 8 unchanged. By estimated dollars.
New positions (44)
| PLTR Palantir Technologies Inc. | 1.32M | New | $246.9M |
| EAT Brinker International, Inc. | 1.19M | New | $229.7M |
| USFD US Foods Holding Corp. | 2.13M | New | $196.2M |
| CLS Celestica, Inc. | 420,855 | New | $152.1M |
| MOG-A Moog Inc. Class A | 323,740 | New | $123.5M |
| CHEF The Chefs' Warehouse, Inc. | 1.02M | New | $114.4M |
| CMG Chipotle Mexican Grill, Inc. | 2.81M | New | $89.8M |
| TDY Teledyne Technologies Incorporated | 140,896 | New | $85.5M |
| MRX Marex Group Limited | 1.17M | New | $81.6M |
| TPG TPG Inc. | 1.84M | New | $81.1M |
Added to (141)
| MU Micron Technology, Inc. | 385,858 | +69.1% | $167.9M |
| RBRK Rubrik, Inc. | 2.39M | +155% | $165.8M |
| FPS Forgent Power Solutions, Inc. | 5.03M | +267% | $137.0M |
| FN Fabrinet | 380,827 | +291% | $120.3M |
| MDB MongoDB, Inc. | 491,763 | +229% | $119.4M |
| ARGX argenx SE · ADR | 175,886 | +208% | $113.9M |
| META Meta Platforms, Inc. | 831,946 | +22.8% | $112.1M |
| V Visa Inc. | 1.07M | +40.6% | $111.1M |
| AXSM Axsome Therapeutics, Inc. | 725,608 | +400% | $107.0M |
| IONS Ionis Pharmaceuticals, Inc. | 2.40M | +56594% | $107.0M |
Trimmed (88)
| FIX Comfort Systems USA, Inc. | 60,877 | -82.9% | -$487.2M |
| GILD Gilead Sciences, Inc. | 55,253 | -95.7% | -$183.7M |
| NTRA Natera, Inc. | 326,960 | -55.0% | -$165.2M |
| P Everpure, Inc. | 676,737 | -58.0% | -$122.3M |
| GWRE Guidewire Software, Inc. | 15,970 | -98.1% | -$117.4M |
| ROKU Roku Inc | 15,446 | -97.8% | -$106.8M |
| RKLB Rocket Lab Corporation | 659,485 | -68.8% | -$101.4M |
| BROS Dutch Bros Inc. | 29,390 | -98.7% | -$83.1M |
| AAPL Apple Inc. | 2.34M | -8.9% | -$76.6M |
| ADPT Adaptive Biotechnologies Corporation | 1.83M | -57.2% | -$70.5M |
Exited (41)
| FTAI FTAI Aviation Ltd. | 2.94M | Exited | -$794.6M |
| VRT Vertiv Holdings Co | 1.05M | Exited | -$353.0M |
| MAR Marriott International | 398,962 | Exited | -$147.9M |
| LGN Legence Corp. | 1.34M | Exited | -$114.4M |
| ORLY O'Reilly Automotive, Inc. | 933,255 | Exited | -$85.9M |
| AZO AutoZone, Inc. | 23,395 | Exited | -$74.8M |
| Nuvalent Inc | 585,583 | Exited | -$72.3M |
| ST Sensata Technologies Holding plc | 1.33M | Exited | -$63.7M |
| HLI Houlihan Lokey, Inc. | 463,415 | Exited | -$62.2M |
| BLDR Builders FirstSource, Inc. | 656,421 | Exited | -$58.7M |
The 10 largest of each, by estimated dollars: shares changed times the later report's price. Index tracking, splits and mergers move positions too.
All positions
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Reported value by quarter
Value and number of positions at the end of each quarter.
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Largest positions in earlier quarters
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Ten largest positions
By value, Q3 2026.
Filings
| Filing | ||||||
|---|---|---|---|---|---|---|
| Q3 2026 | Nov 12, 2026 | 13F-HR | 281 | $30.6B | Current | SEC ↗ |
| Q2 2026 | Aug 12, 2026 | 13F-HR | 278 | $30.6B | Current | SEC ↗ |
| Q1 2026 | May 11, 2026 | 13F-HR | 250 | $23.8B | Current | SEC ↗ |
| Q4 2025 | Feb 11, 2026 | 13F-HR | 241 | $24.0B | Current | SEC ↗ |
| Q3 2025 | Nov 12, 2025 | 13F-HR | 235 | $23.8B | Current | SEC ↗ |
| Q2 2025 | Aug 12, 2025 | 13F-HR | 239 | $23.8B | Current | SEC ↗ |
| Q1 2025 | May 9, 2025 | 13F-HR | 244 | $20.5B | Current | SEC ↗ |
Most recent first, up to 80. An amendment can replace a report or add holdings to it. All 13F filings
Information, not investment advice. Values are the fund's own figures at quarter end; a report can be up to 45 days old when filed. Disclaimer