WESTFIELD CAPITAL MANAGEMENT CO LP
Sector Allocation
- Technology41.3%$12.6B
- Industrials17.3%$5.3B
- Healthcare15.8%$4.8B
- Financials7.3%$2.2B
- Consumer Discretionary6.4%$2.0B
- Materials4.0%$1.2B
- Energy2.5%$759.5M
- Communication Services1.9%$572.8M
- Consumer Staples1.5%$453.9M
- Utilities1.0%$293.6M
AUM History
13fpro.ai/research/fund/westfield-capital-management-co-lp-1177719
Conviction and streaks
Diversifying · top 10 = 29.2%From the fund's last 12 quarters of 13F filings: positions held longest at size, and names it added to or trimmed several quarters running.
Largest positions — Q2 2026
NVDA
$1.6BGOOGL
$1.3BASND
$1.3BAXON
$836.1MFTAI
$794.6MAAPL
$744.7MFIX
$704.5MAVGO
$588.0MMSFT
$527.6MHWM
$516.6MLLY
$499.8MSNOW
$441.9MMKSI
$413.0MMETA
$381.6MVRT
$353.0MGEV
$283.5MMU
$263.4MV
$261.6MAPG
$260.6MTPR
$248.3M
Top 20 stock positions. Options are left out: 13F reports them at the underlying's value.
13fpro.ai/research/fund/westfield-capital-management-co-lp-1177719
WESTFIELD CAPITAL MANAGEMENT CO LP 13F holdings — Q2 2026
$30.6B portfolio (+28.4% QoQ) · 278 holdings · Q2 2026 13F · top 10 are 29% of the stock portfolio
$1.6B
5.3% of stocks
+28%This quarter-3.6%Since filed10+ qtrsHeld$1.3B
4.4% of stocks
+85%This quarter-8.2%Since filed10+ qtrsHeld$1.3B
4.2% of stocks
-0.3%This quarter-4.0%Since filed10+ qtrsHeld$836.1M
2.7% of stocks
+40%This quarter-29.2%Since filed10+ qtrsHeldAIQuality56.7#1,131Est. buyEstimated buy price is Pro: unlock with a free trialAdded 3 qtrs in a row$794.6M
2.6% of stocks
+3%This quarter-30.5%Since filed9 qtrsHeld$744.7M
2.4% of stocks
-18%This quarter+13.8%Since filed10+ qtrsHeldAIQualityAI quality score is Pro: unlock with a free trialEst. buyEstimated buy price is Pro: unlock with a free trialTrimmed 4 qtrs in a row$704.5M
2.3% of stocks
-43%This quarter-28.4%Since filed10+ qtrsHeldAIQualityAI quality score is Pro: unlock with a free trialEst. buyEstimated buy price is Pro: unlock with a free trialTrimmed 4 qtrs in a row$588.0M
1.9% of stocks
+26%This quarter-20.9%Since filed10+ qtrsHeldAIQualityAI quality score is Pro: unlock with a free trialEst. buyEstimated buy price is Pro: unlock with a free trialAdded 2 qtrs in a row$527.6M
1.7% of stocks
-14%This quarter+8.2%Since filed10+ qtrsHeld$516.6M
1.7% of stocks
-16%This quarter-31.0%Since filed6 qtrsHeld
All holdings — WESTFIELD CAPITAL MANAGEMENT CO LP (Q2 2026)
278 disclosed positions from the Form 13F-HR on SEC EDGAR, with quarter-over-quarter share changes. Largest by value first; the ten above are not repeated.
| # | Company | Held | Source | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 11 | ELI LILLY & Co | Healthcare | $499.8M | 1.6% | 417K | +14% | 10+ qtrsAdded 2 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 12 | Snowflake Inc. | Technology | $441.9M | 1.4% | 1.74M | +142% | 5 qtrsAdded 5 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 13 | MKS INC | Technology | $413.0M | 1.4% | 929K | -11% | 4 qtrs | AI quality score is Pro: unlock with a free trial | 13F | |
| 14 | Meta Platforms, Inc. | Technology | $381.6M | 1.3% | 677K | +29% | 10+ qtrs | AI quality score is Pro: unlock with a free trial | 13F | |
| 15 | Vertiv Holdings Co | Technology | $353.0M | 1.1% | 1.05M | -45% | 10+ qtrsTrimmed 2 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 16 | GE Vernova Inc. | Industrials | $283.5M | 0.9% | 241K | +21% | 8 qtrsAdded 2 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 17 | MICRON TECHNOLOGY INC | Technology | $263.4M | 0.9% | 228K | +127% | 2 qtrsAdded 2 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 18 | VISA INC. | Financials | $261.6M | 0.8% | 762K | +67% | 10+ qtrs | AI quality score is Pro: unlock with a free trial | 13F | |
| 19 | APi Group Corp | Industrials | $260.6M | 0.8% | 6.15M | +33% | 3 qtrsAdded 3 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 20 | TAPESTRY, INC. | Consumer Discretionary | $248.3M | 0.8% | 1.70M | -23% | 10+ qtrs | AI quality score is Pro: unlock with a free trial | 13F | |
| 21 | RHYTHM PHARMACEUTICALS, INC. | Healthcare | $245.2M | 0.8% | 2.21M | +14% | 6 qtrsAdded 3 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 22 | Life Time Group Holdings, Inc. | Communication Services | $244.8M | 0.8% | 6.00M | +88% | 2 qtrsAdded 2 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 23 | TAIWAN SEMICONDUCTOR MANUFACTURING CO LTDadr | Technology | $244.0M | 0.8% | 511K | +4% | 10+ qtrsAdded 2 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 24 | Guardant Health, Inc. | Healthcare | $243.7M | 0.8% | 1.62M | +19% | 3 qtrsAdded 3 qtrs in a row | AI quality score is Pro: unlock with a free trial | 13F | |
| 25 | QUANTA SERVICES, INC. | Industrials | $238.7M | 0.8% | 331K | -0.1% | 5 qtrs | AI quality score is Pro: unlock with a free trial | 13F | |
| 26 | $NOW | ServiceNow, Inc. | Technology | $235.7M | 0.8% | 2.37M | +70% | |||
| 27 | $AMD | ADVANCED MICRO DEVICES INC | Technology | $234.2M | 0.8% | 403K | +7930% | |||
| 28 | $PANW | Palo Alto Networks Inc | Technology | $224.5M | 0.7% | 658K | +3% | |||
| 29 | $WWD | Woodward, Inc. | Technology | $224.0M | 0.7% | 527K | +93% | |||
| 30 | $ANET | Arista Networks, Inc. | Technology | $223.7M | 0.7% | 1.32M | +69% | |||
| 31 | $LPLA | LPL Financial Holdings Inc. | Financials | $223.4M | 0.7% | 793K | -10% | |||
| 32 | $RKLB | Rocket Lab Corp | Industrials | $214.9M | 0.7% | 2.11M | -33% | |||
| 33 | $AS | Amer Sports, Inc. | Consumer Discretionary | $214.7M | 0.7% | 6.34M | +61% | |||
| 34 | $NET | Cloudflare, Inc. | Technology | $204.9M | 0.7% | 836K | +54% | |||
| 35 | $AMZN | AMAZON COM INC | Consumer Discretionary | $204.9M | 0.7% | 860K | -62% | |||
| 36 | $GRMN | GARMIN LTD | Technology | $204.5M | 0.7% | 861K | +129% | |||
| 37 | $RRX | REGAL REXNORD CORP | Industrials | $204.1M | 0.7% | 857K | +26% | |||
| 38 | $NTRA | Natera, Inc. | Healthcare | $197.2M | 0.6% | 727K | -4% | |||
| 39 | $MS | MORGAN STANLEY | Financials | $196.6M | 0.6% | 941K | +89% | |||
| 40 | $CRS | CARPENTER TECHNOLOGY CORP | Materials | $193.7M | 0.6% | 314K | New | |||
| 41 | $IOT | Samsara Inc. | Technology | $189.3M | 0.6% | 5.84M | +15% | |||
| 42 | $DT | Dynatrace, Inc. | Technology | $186.6M | 0.6% | 4.25M | +0.9% | |||
| 43 | $CAT | CATERPILLAR INC | Industrials | $186.0M | 0.6% | 175K | +440% | |||
| 44 | $SMTC | SEMTECH CORP | Technology | $183.4M | 0.6% | 1.13M | -12% | |||
| 45 | $AME | AMETEK INC/ | Industrials | $175.1M | 0.6% | 724K | -3% | |||
| 46 | $ABVX | Abivax S.A. | Healthcare | $174.5M | 0.6% | 1.31M | -1.0% | |||
| 47 | $INSM | INSMED Inc | Healthcare | $173.7M | 0.6% | 1.63M | +11% | |||
| 48 | $ITT | ITT INC. | Industrials | $164.2M | 0.5% | 830K | +18% | |||
| 49 | $GILD | GILEAD SCIENCES, INC. | Healthcare | $162.7M | 0.5% | 1.29M | +4724% | |||
| 50 | $PTCT | PTC THERAPEUTICS, INC. | Healthcare | $159.6M | 0.5% | 1.96M | New | |||
| 51 | $BROS | Dutch Bros Inc. | Consumer Discretionary | $156.8M | 0.5% | 2.18M | -6% | |||
| 52 | $CELH | Celsius Holdings, Inc. | Consumer Staples | $155.9M | 0.5% | 5.32M | +41% | |||
| 53 | $MTZ | MASTEC INC | Energy | $155.8M | 0.5% | 374K | +50% | |||
| 54 | $SN | SharkNinja, Inc. | Technology | $153.5M | 0.5% | 1.01M | +11% | |||
| 55 | $CSX | CSX CORP | Industrials | $149.9M | 0.5% | 3.15M | +90% | |||
| 56 | $FCFS | FirstCash Holdings, Inc. | Consumer Discretionary | $149.9M | 0.5% | 693K | +60% | |||
| 57 | $KEY | KEYCORP /NEW/ | Financials | $149.7M | 0.5% | 6.49M | +25% | |||
| 58 | $MCHP | MICROCHIP TECHNOLOGY INC | Technology | $149.5M | 0.5% | 1.64M | +69% | |||
| 59 | $AMAT | APPLIED MATERIALS INC /DE | Technology | $148.6M | 0.5% | 206K | New | |||
| 60 | $MAR | MARRIOTT INTERNATIONAL INC /MD/ | Consumer Discretionary | $147.9M | 0.5% | 399K | +160% | |||
| 61 | $PCVX | Vaxcyte, Inc. | Healthcare | $143.7M | 0.5% | 2.47M | -32% | |||
| 62 | $GL | GLOBE LIFE INC. | Financials | $137.8M | 0.5% | 771K | -8% | |||
| 63 | $FTI | TechnipFMC plc | Energy | $136.6M | 0.5% | 2.06M | +1% | |||
| 64 | $XPO | XPO, Inc. | Industrials | $129.1M | 0.4% | 629K | +10% | |||
| 65 | $LEGN | Legend Biotech Corp | Healthcare | $127.9M | 0.4% | 4.43M | -23% | |||
| 66 | — | EVERPURE INC - CL A | — | $127.0M | 0.4% | 1.61M | -14% | |||
| 67 | $LRCX | LAM RESEARCH CORP | Technology | $123.8M | 0.4% | 286K | New | |||
| 68 | $JLL | JONES LANG LASALLE INC | Real Estate | $123.5M | 0.4% | 398K | +15% | |||
| 69 | $ALAB | Astera Labs, Inc. | Technology | $120.4M | 0.4% | 249K | -71% | |||
| 70 | $ROK | ROCKWELL AUTOMATION, INC | Industrials | $117.4M | 0.4% | 237K | +15% | |||
| 71 | $IEX | IDEX CORP /DE/ | Industrials | $116.6M | 0.4% | 514K | +21% | |||
| 72 | $COHR | COHERENT CORP. | Technology | $114.8M | 0.4% | 291K | -27% | |||
| 73 | $LGN | Legence Corp. | Industrials | $114.4M | 0.4% | 1.34M | -28% | |||
| 74 | $LECO | LINCOLN ELECTRIC HOLDINGS INC | Industrials | $114.4M | 0.4% | 431K | +20% | |||
| 75 | $ASML | ASML HOLDING NV | Technology | $114.3M | 0.4% | 57K | New | |||
| 76 | $PL | Planet Labs PBC | Technology | $113.6M | 0.4% | 3.43M | +109% | |||
| 77 | $ONTO | ONTO INNOVATION INC. | Technology | $113.3M | 0.4% | 299K | -8% | |||
| 78 | $COR | Cencora, Inc. | Consumer Staples | $113.2M | 0.4% | 400K | -8% | |||
| 79 | $RVMD | Revolution Medicines, Inc. | Healthcare | $112.5M | 0.4% | 601K | -61% | |||
| 80 | $SNDK | Sandisk Corp | Technology | $111.5M | 0.4% | 49K | New | |||
| 81 | $AFRM | Affirm Holdings, Inc. | Financials | $110.3M | 0.4% | 1.35M | +25% | |||
| 82 | $LYV | Live Nation Entertainment, Inc. | Communication Services | $108.2M | 0.3% | 591K | -27% | |||
| 83 | $NPO | Enpro Inc. | Materials | $108.0M | 0.3% | 287K | New | |||
| 84 | $PR | Permian Resources Corp | Energy | $106.0M | 0.3% | 5.76M | -23% | |||
| 85 | $ARES | Ares Management Corp | Financials | $106.0M | 0.3% | 952K | -39% | |||
| 86 | $IMAX | IMAX CORP | Technology | $105.8M | 0.3% | 2.65M | +13% | |||
| 87 | $GWRE | Guidewire Software, Inc. | Technology | $103.3M | 0.3% | 839K | +72% | |||
| 88 | $NXT | Nextpower Inc. | Technology | $102.2M | 0.3% | 857K | -23% | |||
| 89 | $FROG | JFrog Ltd | Technology | $101.3M | 0.3% | 1.11M | New | |||
| 90 | $SNPS | SYNOPSYS INC | Technology | $101.2M | 0.3% | 227K | +71% | |||
| 91 | $ROKU | ROKU, INC | Communication Services | $99.0M | 0.3% | 717K | -39% | |||
| 92 | $PLXS | PLEXUS CORP | Technology | $96.8M | 0.3% | 322K | -16% | |||
| 93 | $AIT | APPLIED INDUSTRIAL TECHNOLOGIES INC | Consumer Discretionary | $96.6M | 0.3% | 286K | -1% | |||
| 94 | $MSCI | MSCI Inc. | Financials | $96.3M | 0.3% | 172K | -26% | |||
| 95 | $HOOD | Robinhood Markets, Inc. | Financials | $95.8M | 0.3% | 956K | +51% | |||
| 96 | $ROST | ROSS STORES, INC. | Consumer Discretionary | $94.2M | 0.3% | 442K | -6% | |||
| 97 | $ADPT | Adaptive Biotechnologies Corp | Healthcare | $91.5M | 0.3% | 4.27M | -22% | |||
| 98 | $XENE | Xenon Pharmaceuticals Inc. | Healthcare | $91.0M | 0.3% | 1.51M | +8% | |||
| 99 | $ORLY | O REILLY AUTOMOTIVE INC | Consumer Discretionary | $85.9M | 0.3% | 933K | +5% | |||
| 100 | $C | CITIGROUP INC | Financials | $85.1M | 0.3% | 608K | +1268% | |||
| 101 | $PKG | PACKAGING CORP OF AMERICA | Materials | $84.9M | 0.3% | 356K | +17% | |||
| 102 | $BIRK | Birkenstock Holding plc | Consumer Discretionary | $84.6M | 0.3% | 1.97M | -16% | |||
| 103 | $PLMR | Palomar Holdings, Inc. | Financials | $84.5M | 0.3% | 669K | -22% | |||
| 104 | $EWBC | EAST WEST BANCORP INC | Financials | $83.9M | 0.3% | 650K | -19% | |||
| 105 | $RRR | Red Rock Resorts, Inc. | Consumer Discretionary | $82.1M | 0.3% | 1.26M | +3% | |||
| 106 | $WTFC | WINTRUST FINANCIAL CORP | Financials | $81.0M | 0.3% | 504K | +11% | |||
| 107 | $CLH | CLEAN HARBORS INC | Utilities | $80.2M | 0.3% | 268K | +3% | |||
| 108 | $CWST | CASELLA WASTE SYSTEMS INC | Utilities | $78.8M | 0.3% | 813K | -1% | |||
| 109 | $TTMI | TTM TECHNOLOGIES INC | Technology | $77.8M | 0.3% | 416K | New | |||
| 110 | $TRGP | Targa Resources Corp. | Energy | $77.0M | 0.3% | 287K | -6% | |||
| 111 | $FPS | Forgent Power Solutions, Inc. | Technology | $76.6M | 0.3% | 1.37M | New | |||
| 112 | $ALNY | ALNYLAM PHARMACEUTICALS, INC. | Healthcare | $76.0M | 0.3% | 252K | +3% | |||
| 113 | $COCO | Vita Coco Company, Inc. | Consumer Staples | $75.3M | 0.3% | 1.14M | -1% | |||
| 114 | $RBRK | Rubrik, Inc. | Technology | $75.2M | 0.3% | 937K | New | |||
| 115 | $AZO | AUTOZONE INC | Consumer Discretionary | $74.8M | 0.2% | 23K | -18% | |||
| 116 | $DASH | DoorDash, Inc. | Consumer Discretionary | $74.1M | 0.2% | 402K | -10% | |||
| 117 | $WYNN | WYNN RESORTS LTD | Consumer Discretionary | $73.9M | 0.2% | 761K | +3% | |||
| 118 | $IDXX | IDEXX LABORATORIES INC /DE | Healthcare | $73.7M | 0.2% | 140K | +5% | |||
| 119 | $SFM | Sprouts Farmers Market, Inc. | Consumer Staples | $73.3M | 0.2% | 867K | New | |||
| 120 | $PRAX | Praxis Precision Medicines, Inc. | Healthcare | $73.3M | 0.2% | 219K | New | |||
| 121 | $CRM | Salesforce, Inc. | Technology | $73.2M | 0.2% | 467K | +72% | |||
| 122 | $PRIM | Primoris Services Corp | Energy | $73.1M | 0.2% | 737K | -0.8% | |||
| 123 | $NUVL | Nuvalent, Inc. | Healthcare | $72.3M | 0.2% | 586K | New | |||
| 124 | $DY | DYCOM INDUSTRIES INC | Energy | $71.8M | 0.2% | 142K | New | |||
| 125 | $STEP | StepStone Group Inc. | Financials | $71.5M | 0.2% | 1.73M | +47% | |||
| 126 | $JBHT | HUNT J B TRANSPORT SERVICES INC | Industrials | $71.1M | 0.2% | 246K | +8% | |||
| 127 | $VST | Vistra Corp. | Utilities | $70.7M | 0.2% | 446K | -10% | |||
| 128 | $GKOS | GLAUKOS Corp | Healthcare | $67.6M | 0.2% | 483K | +0.2% | |||
| 129 | $MTSI | MACOM Technology Solutions Holdings, Inc. | Technology | $66.9M | 0.2% | 176K | +33% | |||
| 130 | $TER | TERADYNE, INC | Technology | $66.0M | 0.2% | 136K | New | |||
| 131 | $SAIA | SAIA INC | Industrials | $64.7M | 0.2% | 154K | -1% | |||
| 132 | $NXPI | NXP Semiconductors N.V. | Technology | $63.9M | 0.2% | 227K | -8% | |||
| 133 | $ST | Sensata Technologies Holding plc | Technology | $63.7M | 0.2% | 1.33M | New | |||
| 134 | $HQY | HEALTHEQUITY, INC. | Industrials | $63.5M | 0.2% | 703K | -1% | |||
| 135 | $BTSG | BrightSpring Health Services, Inc. | Healthcare | $62.6M | 0.2% | 898K | New | |||
| 136 | $RLAY | Relay Therapeutics, Inc. | Healthcare | $62.6M | 0.2% | 3.34M | New | |||
| 137 | $HLI | HOULIHAN LOKEY, INC. | Financials | $62.2M | 0.2% | 463K | -15% | |||
| 138 | $ENTG | ENTEGRIS INC | Materials | $62.0M | 0.2% | 345K | -7% | |||
| 139 | $CORZ | Core Scientific, Inc./tx | Financials | $61.7M | 0.2% | 2.41M | +63% | |||
| 140 | $RDNT | RadNet, Inc. | Healthcare | $60.2M | 0.2% | 976K | +83% | |||
| 141 | $ORKA | Oruka Therapeutics, Inc. | Healthcare | $60.1M | 0.2% | 631K | +102% | |||
| 142 | $CRDO | Credo Technology Group Holding Ltd | Technology | $59.0M | 0.2% | 217K | -77% | |||
| 143 | $BLDR | Builders FirstSource, Inc. | Industrials | $58.7M | 0.2% | 656K | New | |||
| 144 | $LSCC | LATTICE SEMICONDUCTOR CORP | Technology | $58.4M | 0.2% | 382K | -32% | |||
| 145 | $DSGX | DESCARTES SYSTEMS GROUP INC | Technology | $57.8M | 0.2% | 835K | +4% | |||
| 146 | $AVNT | AVIENT CORP | Materials | $57.3M | 0.2% | 1.55M | -1% | |||
| 147 | $BRZE | Braze, Inc. | Technology | $56.8M | 0.2% | 2.62M | -34% | |||
| 148 | $FN | Fabrinet | Technology | $54.7M | 0.2% | 97K | -66% | |||
| 149 | $LNG | Cheniere Energy, Inc. | Energy | $54.6M | 0.2% | 228K | -50% | |||
| 150 | $PODD | INSULET CORP | Healthcare | $53.7M | 0.2% | 353K | New |
What changed in Q2 2026
Against the previous quarter's 13F: 68 new, 98 added to, 104 trimmed, 40 sold out. Share-count changes; largest moves by dollar size first.
New positions (68)
$CRSCARPENTER TECHNOLOGY CORP$193.7M
first bought this quarter
$PTCTPTC THERAPEUTICS, INC.$159.6M
first bought this quarter
$LRCXLAM RESEARCH CORP$123.8M
first bought this quarter
$ASMLASML HOLDING NV$114.3M
first bought this quarter
$SNDKSandisk Corp$111.5M
first bought this quarter
$NPOEnpro Inc.$108.0M
first bought this quarter
+62 more in the Excel export
Added to (98)
now $1.3B · held 10+ qtrs
now $1.6B · held 10+ qtrs, 2 adds in a row
now $441.9M · held 5 qtrs, 5 adds in a row
now $836.1M · held 10+ qtrs, 3 adds in a row
$AMDADVANCED MICRO DEVICES INC+7930%
now $234.2M · held 3 qtrs
$GILDGILEAD SCIENCES, INC.+4724%
now $162.7M · held 3 qtrs
+92 more in the Excel export
Trimmed (104)
now $704.5M · held 10+ qtrs, 4 trims in a row
$MRVLMarvell Technology, Inc.-99%
now $3.9M
$BEBloom Energy Corp-99%
now $3.2M
$AMZNAMAZON COM INC-62%
now $204.9M · held 10+ qtrs, 5 trims in a row
$ALABAstera Labs, Inc.-71%
now $120.4M · held 4 qtrs
now $353.0M · held 10+ qtrs, 2 trims in a row
+98 more in the Excel export
Sold out (40)
$KTOSKRATOS DEFENSE & SECURITY SOLUTIONS, INC.was $110.2M
held 3 qtrs
$AIGAMERICAN INTERNATIONAL GROUP, INC.was $109.8M
held 1 qtr
$PLTRPalantir Technologies Inc.was $98.7M
held 8 qtrs
$WGSGeneDx Holdings Corp.was $87.9M
held 5 qtrs
$FFIVF5, INC.was $86.4M
$CHRWC. H. ROBINSON WORLDWIDE, INC.was $71.3M
+34 more in the Excel export
Holdings by quarter
Every 13F WESTFIELD CAPITAL MANAGEMENT CO LP has filed, 41 earlier quarters. Pick one to see what it held then.
Is it too late to follow WESTFIELD CAPITAL MANAGEMENT?
Q2 2026 13F filed with the SEC on Aug 12, 2026. Prices are closing prices as of Oct 26, 2026.
Average quality of WESTFIELD CAPITAL MANAGEMENT's top 20 holdings: 74/100 (our AI quality score, weighted by position size; 19 of the 20 are scored)
Top 10 since filing
-11.7%
Value-weighted move of the 10 largest stock positions
Turnover
24%
Last quarter; 71% over the last 4
Top 10 weight
29%
Share of the stock portfolio in its 10 largest positions
Held 4+ quarters
72%
Share of portfolio value in positions held a year or more
Highest-quality names it owns(among its 100 largest positions)
The 8 highest-scoring companies in this portfolio are a Pro feature.
How these are measured
- Moves since the quarter-end and since the filing date use our own daily closing prices, from the close on (or just before) each date to the latest close.
- Turnover is the lesser of shares bought or sold in a quarter, valued at the quarter-end prices in the 13F, divided by the average of the two quarters' stock portfolio values.
- Quarters held and add/trim streaks count back only through quarters whose filed holdings add up to the filing's own cover-page total (back to Q1 2024 for this fund). A change counts as an add or a trim when the split-adjusted share count moves by more than 1%.
- Estimate, not the fund's reported cost. For each quarter in the current holding period in which the fund's share count rose (split-adjusted), we take that quarter's average daily close and weight it by the shares added; sales do not change an average cost. Quarters where the stock's price history and the 13F's own implied price disagree by more than 2x are left out.
- Put and call option rows report the value of the underlying shares, not a position the fund paid for, so they are left out of all of the above.
Portfolio Overview
WESTFIELD CAPITAL MANAGEMENT CO LP disclosed 278 positions worth $30.6B in its Form 13F-HR for Q2 2026, led by $NVDA (NVIDIA CORP) at 5.3% of the equity portfolio, followed by $GOOGL and $ASND. During the quarter the fund opened 68 new positions and exited 40 — including a new stake in $CRS and a full exit from $KTOS. The portfolio is most concentrated in Technology (41.3% of disclosed assets). All figures are sourced directly from WESTFIELD CAPITAL MANAGEMENT CO LP’s Form 13F-HR filing with the SEC under CIK 1177719.
Funds like this
managers whose biggest positions overlap WESTFIELD CAPITAL MANAGEMENT'sBrowse Top Institutional Investors
13F Pro tracks 8,700+ institutional investors filing 13F reports with the SEC.
to search all 8,700+ institutional filers.
AI-Powered Hedge Fund Analysis: WESTFIELD CAPITAL MANAGEMENT CO LP
13F Pro is an AI hedge fund tracker and stock research platform. For WESTFIELD CAPITAL MANAGEMENT CO LP (SEC CIK: 1177719), the platform ingests every quarterly Form 13F filing and applies AI-powered analysis on top — 10 specialized AI analysts (value, growth, momentum, macro, activist, and more) debate the fund's top positions and publish AI-generated analysis with cited SEC sources.
Every holding in WESTFIELD CAPITAL MANAGEMENT CO LP's portfolio is scored on an AI quality ranking built from its SEC filings (ROIC, FCF margin, revenue growth, institutional flow, earnings quality, shareholder dilution, and more). Track accumulation and distribution quarter over quarter, identify conviction positions, and see AI stock analysis for each position — alongside 8,700+ other institutional filers and 2,800+ AI-ranked companies.