Westfield Capital Management Co. LP
In its 13F for Q2 2024 (holdings as of June 30, 2024, filed August 14, 2024), Westfield Capital Management Co. LP reported 248 stock positions worth $20.4 billion. Its top holding was Nvidia (NVDA) at 4.3% of the portfolio, followed by Microsoft (MSFT, 4.1%) and Apple (AAPL, 3.9%). Compared with Q1 2024, it opened 31 new positions, sold out of 27, added to 138 and reduced 67. The biggest buy was Nvidia (NVDA, shares +18%) and the biggest sale Builders Firstsource (BLDR, shares −99%).
- Most Recent 13F
- Q2 2026
- Location
- BOSTON, MA
- CIK
- 0001177719
- Portfolio Value
- $20.4B (Q2 2024)
- SEC Filing
- 0001085146-24-003888 ↗ filed Aug 14, 2024
Holdings Value
Holdings 248 stocks · $20.4B
| NVDA Nvidia Corp. | 4.31% | 7,096,952 | $876.8M | Add +18.3% |
| MSFT Microsoft Corp. | 4.06% | 1,846,637 | $825.4M | Add +21.3% |
| AAPL Apple Inc. | 3.94% | 3,812,231 | $802.9M | Add +17.8% |
| ASND Ascendis Pharma A/S | 3.33% | 4,962,824 | $676.8M | Add +21.8% |
| AMZN Amazon.com Inc. | 3.11% | 3,279,806 | $633.8M | Add +24.5% |
| GOOGL Alphabet Inc. Class A | 2.78% | 3,100,861 | $564.8M | Add +4.9% |
| TDG Transdigm Group Inc. | 2.28% | 363,406 | $464.3M | Add +15.2% |
| META Meta Platforms Inc. Class A | 2.13% | 861,572 | $434.4M | Add +22.6% |
| VRT Vertiv Holdings Co. Class A | 1.52% | 3,570,870 | $309.1M | Add +5.0% |
| AXON Axon Enterprise Inc. | 1.51% | 1,047,559 | $308.2M | Add +47.7% |
| NOW ServiceNow Inc. | 1.38% | 358,202 | $281.8M | Add +27.3% |
| FIX Comfort Systems USA Inc. | 1.29% | 864,869 | $263.0M | Add +29.7% |
| V Visa Inc. Class A | 1.14% | 882,448 | $231.6M | Reduce -13.5% |
| DXCM Dexcom Inc. | 1.09% | 1,965,318 | $222.8M | Add +27.7% |
| LEGN Legend Biotech Corp.-ADR | 1.04% | 4,772,209 | $211.4M | Add +113.1% |
| UBER Uber Technologies Inc. | 1.01% | 2,827,566 | $205.5M | Add +60.0% |
| PGR Progressive Corp. | 0.93% | 914,475 | $189.9M | Add +48.1% |
| WING Wingstop Inc. | 0.91% | 436,479 | $184.5M | Add +38.6% |
| TSM Taiwan Semiconductor-SP ADR | 0.91% | 1,060,028 | $184.2M | Add +24.1% |
| ABBV Abbvie Inc. | 0.85% | 1,005,058 | $172.4M | Add +13.3% |
| CDNS Cadence Design SYS Inc. | 0.83% | 550,394 | $169.4M | Add +48.5% |
| ICLR Icon PLC | 0.81% | 527,751 | $165.4M | Reduce -1.7% |
| LPLA LPL Financial Holdings Inc. | 0.80% | 584,601 | $163.3M | Add +51.8% |
| OPCH Option Care Health Inc. | 0.80% | 5,892,563 | $163.2M | Add +13.9% |
| CMG Chipotle Mexican Grill Inc. | 0.79% | 2,558,292 | $160.3M | Add +39.9% |
| CRM Salesforce Inc. | 0.78% | 613,741 | $157.8M | Add +3.9% |
| PCVX Vaxcyte Inc. | 0.72% | 1,929,348 | $145.7M | Add +21.6% |
| MASI Masimo Corp. | 0.70% | 1,131,686 | $142.5M | Add +64.9% |
| MNDY Monday.com Ltd. | 0.69% | 586,075 | $141.1M | Add +41.0% |
| AIG American International Group | 0.67% | 1,827,946 | $135.7M | Add +33.8% |
| TXRH Texas Roadhouse Inc. | 0.67% | 789,392 | $135.5M | Add +6.6% |
| SAP Sap SE-Sponsored ADR | 0.67% | 671,132 | $135.4M | Add +122.1% |
| ARES Ares Management Corp. Class A | 0.65% | 992,416 | $132.3M | Add +52.8% |
| DKNG Draftkings Inc. Class A | 0.65% | 3,461,599 | $132.1M | Add +72.4% |
| LNTH Lantheus Holdings Inc. | 0.65% | 1,641,158 | $131.8M | Reduce -16.2% |
| MHO M/I Homes Inc. | 0.64% | 1,067,532 | $130.4M | Reduce -12.5% |
| SAIA Saia Inc. | 0.63% | 271,591 | $128.8M | Add +4.8% |
| CSGP Costar Group Inc. | 0.63% | 1,719,913 | $127.5M | Add +4.4% |
| FICO Fair Isaac Corp. | 0.61% | 83,453 | $124.2M | Add +7.9% |
| COST Costco Wholesale Corp. | 0.61% | 145,392 | $123.6M | Reduce -14.1% |
| MDB Mongodb Inc. | 0.60% | 488,722 | $122.2M | Add +120.3% |
| AMD Advanced Micro Devices | 0.59% | 746,157 | $121.0M | Add +140.6% |
| PODD Insulet Corp. | 0.59% | 591,484 | $119.4M | Add +26.3% |
| NXPI NXP Semiconductors NV | 0.59% | 443,517 | $119.3M | Add +18.4% |
| WSC Willscot Holdings Corp. | 0.59% | 3,164,403 | $119.1M | Add +15.0% |
| PTC PTC Inc. | 0.57% | 638,228 | $115.9M | Add +36.6% |
| OWL Blue Owl Capital Inc. | 0.56% | 6,443,066 | $114.4M | Add +42.3% |
| ROST Ross Stores Inc. | 0.56% | 786,739 | $114.3M | Add +9.1% |
| HUBS HubSpot Inc. | 0.56% | 193,212 | $114.0M | Reduce -0.6% |
| IOT Samsara Inc. Class A | 0.56% | 3,367,979 | $113.5M | Add +51.1% |
| STZ Constellation Brands Inc. Class A | 0.56% | 441,031 | $113.5M | Add +3.3% |
| MTSI Macom Technology Solutions H | 0.55% | 1,000,396 | $111.5M | Add +126.7% |
| HD Home Depot Inc. | 0.53% | 310,668 | $106.9M | Reduce -17.1% |
| PLTR Palantir Technologies Inc. Class A | 0.53% | 4,220,141 | $106.9M | New |
| AVY Avery Dennison Corp. | 0.52% | 488,344 | $106.8M | Add +8.4% |
| FOUR SHIFT4 Payments Inc. Class A | 0.52% | 1,442,281 | $105.8M | Add +8.2% |
| FFIV F5 Inc. | 0.52% | 609,615 | $105.0M | Add +18.3% |
| UNH Unitedhealth Group Inc. | 0.51% | 204,454 | $104.1M | Reduce -52.1% |
| GLOB Globant SA | 0.50% | 576,123 | $102.7M | New |
| UNP Union Pacific Corp. | 0.47% | 427,272 | $96.7M | Add +1.1% |
| RCKT Rocket Pharmaceuticals Inc. | 0.46% | 4,327,922 | $93.2M | Add +8.6% |
| DT Dynatrace Inc. | 0.45% | 2,054,964 | $91.9M | Add +6.8% |
| FTAI Ftai Aviation Ltd. | 0.45% | 887,014 | $91.6M | New |
| GPN Global Payments Inc. | 0.45% | 939,034 | $90.8M | Add +8.7% |
| CWST Casella Waste Systems Inc. Class A | 0.44% | 910,818 | $90.4M | Add +7.4% |
| HUBB Hubbell Inc. | 0.44% | 243,728 | $89.1M | Add +8.1% |
| TSLA Tesla Inc. | 0.43% | 437,997 | $86.7M | Add +50.5% |
| CPRT Copart Inc. | 0.43% | 1,597,802 | $86.5M | Reduce -26.3% |
| FLEX Flex Ltd. | 0.42% | 2,932,165 | $86.5M | Add +62.8% |
| FLYW Flywire Corp.-Voting | 0.42% | 5,220,396 | $85.6M | Add +7.9% |
| ITT Itt Inc. | 0.41% | 641,634 | $82.9M | Reduce -11.3% |
| ST Sensata Technologies Holdplc | 0.40% | 2,191,327 | $81.9M | Add +77.7% |
| ROK Rockwell Automation Inc. | 0.40% | 296,166 | $81.5M | Reduce -2.7% |
| SCHW Schwab (charles) Corp. | 0.39% | 1,086,071 | $80.0M | Add +16.8% |
| PR Permian Resources Corp. Class A | 0.39% | 4,951,636 | $80.0M | Add +9.0% |
| COHR Coherent Corp. | 0.39% | 1,092,405 | $79.2M | Reduce -3.3% |
| IEX Idex Corp. | 0.39% | 391,140 | $78.7M | Add +8.7% |
| RRX Regal Rexnord Corp. | 0.39% | 579,872 | $78.4M | Add +91.7% |
| BFAM Bright Horizons Family Solut | 0.37% | 685,448 | $75.5M | Add +8.5% |
| VMC Vulcan Materials Co. | 0.37% | 303,078 | $75.4M | Reduce -2.7% |
| APO Apollo Global Management Inc. | 0.37% | 629,577 | $74.3M | Reduce -29.0% |
| NSIT Insight Enterprises Inc. | 0.36% | 374,339 | $74.3M | Reduce -7.7% |
| AME Ametek Inc. | 0.36% | 442,996 | $73.9M | Reduce -53.5% |
| CDW CDW Corp. | 0.36% | 329,713 | $73.8M | Reduce -1.4% |
| DDOG Datadog Inc. Class A | 0.36% | 566,746 | $73.5M | Add +13.4% |
| JBHT Hunt (jb) Transprt SVCS Inc. | 0.36% | 456,823 | $73.1M | Add +5.9% |
| SUI Sun Communities Inc. filed as SUN CMNTYS INC | 0.36% | 604,452 | $72.7M | Add +0.1% |
| ITCI Intra-Cellular Therapies Inc. | 0.35% | 1,042,862 | $71.4M | New |
| OVV Ovintiv Inc. | 0.35% | 1,510,039 | $70.8M | Add +9.0% |
| NOG Northern Oil and Gas Inc. | 0.34% | 1,878,499 | $69.8M | Add +7.4% |
| FANG Diamondback Energy Inc. | 0.34% | 348,608 | $69.8M | Add +0.9% |
| CSCO Cisco Systems Inc. | 0.34% | 1,453,819 | $69.1M | Reduce -13.8% |
| AXTA Axalta Coating Systems Ltd. | 0.34% | 2,012,196 | $68.8M | Add +7.0% |
| GEHC GE Healthcare Technology | 0.34% | 877,859 | $68.4M | Add +33.9% |
| AZEK The Azek Co. Inc. | 0.34% | 1,622,142 | $68.3M | Add +9.0% |
| S Sentinelone Inc. Class A | 0.33% | 3,201,739 | $67.4M | New |
| ASML ASML Holding NV-NY Reg SHS | 0.33% | 65,541 | $67.0M | New |
| NBIX Neurocrine Biosciences Inc. | 0.33% | 484,777 | $66.7M | Reduce -3.7% |
| AJG Arthur J Gallagher & Co. filed as GALLAGHER ARTHUR J & CO | 0.33% | 256,239 | $66.4M | Reduce -12.1% |
| BIO Bio-Rad Laboratories-A | 0.33% | 243,185 | $66.4M | Add +5.5% |
Portfolio Sells Q1 2024 → Q2 2024
| BLDR Builders Firstsource Inc. | Reduce -99.4% | 0.01% | −1.51 |
| NICE Nice Ltd. - Spon ADR | Sold out | 0.00% | −0.78 |
| LECO Lincoln Electric Holdings | Reduce -64.4% | 0.21% | −0.65 |
| INSP Inspire Medical Systems Inc. | Sold out | 0.00% | −0.61 |
| UNH Unitedhealth Group Inc. | Reduce -52.1% | 0.51% | −0.60 |
| AME Ametek Inc. | Reduce -53.5% | 0.36% | −0.55 |
| WDAY Workday Inc. Class A | Sold out | 0.00% | −0.50 |
| AVTR Avantor Inc. | Reduce -47.7% | 0.29% | −0.42 |
| MKSI MKS Inc. | Reduce -96.1% | 0.02% | −0.42 |
| HXL Hexcel Corp. | Sold out | 0.00% | −0.39 |
| V Visa Inc. Class A | Reduce -13.5% | 1.14% | −0.36 |
| FIVE Five Below | Reduce -95.1% | 0.01% | −0.35 |
| MSTR Strategy Inc. | Reduce -99.3% | 0.00% | −0.32 |
| EQIX Equinix Inc. | Sold out | 0.00% | −0.30 |
| MGM MGM Resorts International | Reduce -44.2% | 0.29% | −0.30 |
| SMCI Super Micro Computer Inc. | Reduce -98.3% | 0.00% | −0.29 |
| G Genpact Ltd. | Sold out | 0.00% | −0.27 |
| DECK Deckers Outdoor Corp. | Sold out | 0.00% | −0.25 |
| SBAC SBA Communications Corp. | Sold out | 0.00% | −0.24 |
| CPRT Copart Inc. | Reduce -26.3% | 0.43% | −0.23 |
| MHO M/I Homes Inc. | Reduce -12.5% | 0.64% | −0.23 |
| DAY Dayforce Inc. | Reduce -52.9% | 0.11% | −0.23 |
| WDC Western Digital Corp. | Sold out | 0.00% | −0.23 |
| HD Home Depot Inc. | Reduce -17.1% | 0.53% | −0.23 |
| IDXX Idexx Laboratories Inc. | Reduce -34.5% | 0.27% | −0.22 |
| PANW Palo Alto Networks Inc. | Sold out | 0.00% | −0.21 |
| CE Celanese Corp. | Reduce -21.4% | 0.27% | −0.20 |
| HAL Halliburton Co. | Sold out | 0.00% | −0.20 |
| APTV Aptiv Irish Holdings Ltd. | Sold out | 0.00% | −0.20 |
| REXR Rexford Industrial Realty Inc. | Sold out | 0.00% | −0.19 |
| LULU Lululemon Athletica Inc. | Reduce -99.2% | 0.00% | −0.18 |
| EXPE Expedia Group Inc. | Sold out | 0.00% | −0.18 |
| SMAR Smartsheet Inc. Class A | Reduce -40.5% | 0.31% | −0.17 |
| APO Apollo Global Management Inc. | Reduce -29.0% | 0.37% | −0.16 |
| PCOR Procore Technologies Inc. | Reduce -21.1% | 0.23% | −0.15 |
| SIMO Silicon Motion Technol-ADR | Sold out | 0.00% | −0.15 |
| MTH Meritage Homes Corp. | Reduce -22.4% | 0.30% | −0.15 |
| SIGI Selective Insurance Group | Reduce -39.1% | 0.14% | −0.15 |
| PLXS Plexus Corp. | Reduce -77.5% | 0.04% | −0.15 |
| HLT Hilton Worldwide Holdings Inc. | Reduce -31.0% | 0.28% | −0.14 |
| MSCI MSCI Inc. | Reduce -14.9% | 0.30% | −0.14 |
| ICLR Icon PLC | Reduce -1.7% | 0.81% | −0.13 |
| COO The Cooper Cos Inc. | Reduce -15.2% | 0.28% | −0.13 |
| KNSL Kinsale Capital Group Inc. | Reduce -15.1% | 0.17% | −0.12 |
| RRR Red Rock Resorts Inc. Class A | Reduce -17.5% | 0.30% | −0.12 |
| WEX Wex Inc. | Reduce -8.2% | 0.21% | −0.12 |
| ALGN Align Technology Inc. | Reduce -2.5% | 0.23% | −0.11 |
| ITT Itt Inc. | Reduce -11.3% | 0.41% | −0.11 |
| CSCO Cisco Systems Inc. | Reduce -13.8% | 0.34% | −0.10 |
| CALX Calix Inc. | Sold out | 0.00% | −0.10 |
Portfolio Buys Q1 2024 → Q2 2024
| NVDA Nvidia Corp. | Add +18.3% | 4.31% | +1.46 |
| AAPL Apple Inc. | Add +17.8% | 3.94% | +1.03 |
| MSFT Microsoft Corp. | Add +21.3% | 4.06% | +0.69 |
| AMZN Amazon.com Inc. | Add +24.5% | 3.11% | +0.62 |
| PLTR Palantir Technologies Inc. Class A | New | 0.53% | +0.53 |
| GLOB Globant SA | New | 0.50% | +0.50 |
| FTAI Ftai Aviation Ltd. | New | 0.45% | +0.45 |
| GOOGL Alphabet Inc. Class A | Add +4.9% | 2.78% | +0.43 |
| LEGN Legend Biotech Corp.-ADR | Add +113.1% | 1.04% | +0.38 |
| SAP Sap SE-Sponsored ADR | Add +122.1% | 0.67% | +0.36 |
| ITCI Intra-Cellular Therapies Inc. | New | 0.35% | +0.35 |
| AXON Axon Enterprise Inc. | Add +47.7% | 1.51% | +0.35 |
| META Meta Platforms Inc. Class A | Add +22.6% | 2.13% | +0.34 |
| S Sentinelone Inc. Class A | New | 0.33% | +0.33 |
| ASML ASML Holding NV-NY Reg SHS | New | 0.33% | +0.33 |
| MTSI Macom Technology Solutions H | Add +126.7% | 0.55% | +0.33 |
| AMD Advanced Micro Devices | Add +140.6% | 0.59% | +0.30 |
| WING Wingstop Inc. | Add +38.6% | 0.91% | +0.30 |
| UBER Uber Technologies Inc. | Add +60.0% | 1.01% | +0.30 |
| TSM Taiwan Semiconductor-SP ADR | Add +24.1% | 0.91% | +0.29 |
| ODD Oddity Tech Ltd. Class A | New | 0.29% | +0.29 |
| LPLA LPL Financial Holdings Inc. | Add +51.8% | 0.80% | +0.27 |
| NU Nu Holdings Ltd./Cayman Isl-A | New | 0.26% | +0.26 |
| PGR Progressive Corp. | Add +48.1% | 0.93% | +0.26 |
| KD Kyndryl Holdings Inc. | New | 0.26% | +0.26 |
| NOW ServiceNow Inc. | Add +27.3% | 1.38% | +0.26 |
| TTD Trade Desk Inc./the Class A | New | 0.25% | +0.25 |
| P Everpure Inc. Class A | New | 0.24% | +0.24 |
| TER Teradyne Inc. | New | 0.24% | +0.24 |
| TDG Transdigm Group Inc. | Add +15.2% | 2.28% | +0.24 |
| CMG Chipotle Mexican Grill Inc. | Add +39.9% | 0.79% | +0.23 |
| CDNS Cadence Design SYS Inc. | Add +48.5% | 0.83% | +0.23 |
| COIN Coinbase Global Inc. Class A | New | 0.22% | +0.22 |
| MNDY Monday.com Ltd. | Add +41.0% | 0.69% | +0.20 |
| ROKU Roku Inc. | New | 0.20% | +0.20 |
| ARES Ares Management Corp. Class A | Add +52.8% | 0.65% | +0.20 |
| VECO Veeco Instruments Inc. | New | 0.20% | +0.20 |
| MCHP Microchip Technology Inc. | Add +322.2% | 0.25% | +0.19 |
| MDB Mongodb Inc. | Add +120.3% | 0.60% | +0.18 |
| ALGM Allegro Microsystems Inc. | New | 0.18% | +0.18 |
| FIX Comfort Systems USA Inc. | Add +29.7% | 1.29% | +0.18 |
| ENV Envestnet Inc. | New | 0.17% | +0.17 |
| MASI Masimo Corp. | Add +64.9% | 0.70% | +0.17 |
| DKNG Draftkings Inc. Class A | Add +72.4% | 0.65% | +0.17 |
| CCJ Cameco Corp. | Add +5054.5% | 0.17% | +0.17 |
| PODD Insulet Corp. | Add +26.3% | 0.59% | +0.17 |
| ST Sensata Technologies Holdplc | Add +77.7% | 0.40% | +0.16 |
| TSLA Tesla Inc. | Add +50.5% | 0.43% | +0.16 |
| FLEX Flex Ltd. | Add +62.8% | 0.42% | +0.15 |
| PCVX Vaxcyte Inc. | Add +21.6% | 0.72% | +0.15 |
All Filings
| Quarter | Positions | 13F Reported Value | Top Holdings |
|---|---|---|---|
| Q2 2026 | 278 | $30.6B | NVDA, GOOGL, ASND, AXON, FTAI |
| Q1 2026 | 250 | $23.8B | NVDA, ASND, FIX, AAPL, FTAI |
| Q4 2025 | 241 | $24.0B | NVDA, ASND, AAPL, MSFT, GOOGL |
| Q3 2025 | 235 | $23.8B | NVDA, ASND, MSFT, AAPL, FIX |
| Q2 2025 | 239 | $23.8B | NVDA, ASND, MSFT, AAPL, AMZN |
| Q1 2025 | 244 | $20.5B | ASND, NVDA, AAPL, MSFT, AMZN |
| Q4 2024 | 239 | $23.0B | NVDA, AAPL, MSFT, ASND, AMZN |
| Q3 2024 | 247 | $22.1B | NVDA, AAPL, MSFT, ASND, AMZN |
| Q2 2024 | 248 | $20.4B | NVDA, MSFT, AAPL, ASND, AMZN |
| Q1 2024 | 244 | $19.0B | MSFT, ASND, AAPL, NVDA, AMZN |