WESTFIELD CAPITAL MANAGEMENT CO LP — 13F Holdings

2026 Q1  ·  287 Positions

2026 Q1 Portfolio Activity

In 2026 Q1, WESTFIELD CAPITAL MANAGEMENT CO LP maintained a portfolio of 287 distinct positions. The most significant new addition was CHENIERE ENERGY INC, now representing 0.55% of the total fund value. They heavily accumulated shares in FTAI AVIATION LTD, increasing the position by 21.2%. The fund also reduced its exposure to BANK AMERICA CORP by 72.1%.
Position History hover any row below to update
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WESTFIELD CAPITAL MANAGEMENT CO LP Boston, MA Registered Investment Advisor AUM $23,835M
PCA Score Concentration Risk
Risk ENB
Total Positions
287
Quarter
2026 Q1
Top Holding
NVDA (4.6%)
Top 10 Concentration
30.3%
Turnover Rate
23.4%
Sector HHI
0.18
Items per page:
Showing 1-50 of 287

WESTFIELD CAPITAL MANAGEMENT CO LP Full Holdings List — 2026 Q1

Stock History Sector / Type Port % Prev % Rank / Prev Conviction
Freshness
Change % Change Influence Shares Mkt Value Avg Cost Price Held 1st Owned Source Source Date Date Reported
NVDA
NVIDIA CORPORAT...
Technology 4.62% 4.62% #1
Prev: #1
5.8
365,990 6.2%
P
S
6,317,039 $1,101,691,587 2003 Q4 13F Filing 2026-03-31 2026-05-11
ASND
ASCENDIS PHARMA...
Healthcare 4.62% 4.61% #2
Prev: #2
3.8
-372,256 -7.2%
P
S
4,813,440 $1,100,978,089 2018 Q2 13F Filing 2026-03-31 2026-05-11
FIX
COMFORT SYS USA...
Industrials 3.59% 2.60% #3 3
Prev: #6
2.9
-47,920 -7.2%
P
S
620,915 $856,235,416 2023 Q4 13F Filing 2026-03-31 2026-05-11
AAPL
APPLE INC
Technology 3.34% 3.71% #4 1
Prev: #3
2.3
-141,205 -4.3%
P
S
3,133,113 $795,152,846 2002 Q2 13F Filing 2026-03-31 2026-05-11
FTAI
FTAI AVIATION L...
Industrials 2.93% 1.93% #5 4
Prev: #9
4.2
497,602 21.2%
P
S
2,848,227 $697,815,609 2024 Q2 13F Filing 2026-03-31 2026-05-11
MSFT
MICROSOFT CORP
Technology 2.56% 3.27% #6 2
Prev: #4
1.5
28,294 1.7%
P
S
1,649,513 $610,600,060 2002 Q2 13F Filing 2026-03-31 2026-05-11
GOOGL
ALPHABET INC
Communication Services 2.45% 2.84% #7 2
Prev: #5
1.5
-151,734 -7.0%
P
S
2,026,744 $582,810,504 2015 Q4 13F Filing 2026-03-31 2026-05-11
HWM
HOWMET AEROSPAC...
Industrials 2.21% 1.90% #8 2
Prev: #10
1.4
70,572 3.2%
P
S
2,289,697 $527,683,511 2025 Q1 13F Filing 2026-03-31 2026-05-11
VRT
VERTIV HOLDINGS...
Industrials 2.02% 1.54% #9 4
Prev: #13
1.3
-356,020 -15.6%
P
S
1,921,696 $481,538,482 2023 Q3 13F Filing 2026-03-31 2026-05-11
AMZN
AMAZON COM INC
Consumer Cyclical 1.99% 2.24% #10 3
Prev: #7
1.3
-51,116 -2.2%
P
S
2,279,654 $474,783,586 2009 Q3 13F Filing 2026-03-31 2026-05-11
AXON
AXON ENTERPRISE...
Industrials 1.90% 1.97% #11 3
Prev: #8
3.3
232,957 28.0%
P
S
1,064,134 $451,927,224 2022 Q4 13F Filing 2026-03-31 2026-05-11
AVGO
BROADCOM INC
Technology 1.61% 1.60% #12
Prev: #12
2.6
124,607 11.2%
P
S
1,236,925 $382,840,683 2016 Q1 13F Filing 2026-03-31 2026-05-11
LLY
ELI LILLY & CO
Healthcare 1.41% 1.24% #13 1
Prev: #14
3.1
87,030 31.4%
P
S
364,579 $335,329,189 2006 Q3 13F Filing 2026-03-31 2026-05-11
TPR
TAPESTRY INC
Consumer Cyclical 1.30% 1.12% #14 1
Prev: #15
1.0
100,758 4.8%
P
S
2,198,862 $310,281,358 2021 Q1 13F Filing 2026-03-31 2026-05-11
META
META PLATFORMS ...
Communication Services 1.26% 1.80% #15 4
Prev: #11
1.0
-128,461 -19.6%
P
S
526,822 $301,410,388 2013 Q3 13F Filing 2026-03-31 2026-05-11
LPLA
LPL FINL HLDGS ...
Financial Services 1.11% 0.93% #16 2
Prev: #18
2.9
255,944 40.9%
P
S
881,506 $265,183,525 2013 Q4 13F Filing 2026-03-31 2026-05-11
MKSI
MKS INC.
Technology 1.01% 0.56% #17 25
Prev: #42
2.9
206,990 24.6%
P
S
1,046,763 $240,556,578 2017 Q3 13F Filing 2026-03-31 2026-05-11
INSM
INSMED INC
Healthcare 1.01% 0.31% #18 87
Prev: #105
3.4
1,035,938 239.5%
P
S
1,468,459 $240,122,429 2020 Q2 13F Filing 2026-03-31 2026-05-11
PCVX
VAXCYTE INC
Healthcare 0.89% 0.68% #19 13
Prev: #32
0.9
106,421 3.0%
P
S
3,646,138 $211,877,079 2023 Q3 13F Filing 2026-03-31 2026-05-11
RKLB
ROCKET LAB CORP
Industrials 0.85% 0.75% #20 5
Prev: #25
2.8
580,168 22.4%
P
S
3,172,611 $203,745,048 2024 Q4 13F Filing 2026-03-31 2026-05-11
NFLX
NETFLIX INC.
Communication Services 0.79% 0.62% #21 13
Prev: #34
2.8
372,447 23.3%
P
S
1,969,994 $189,414,876 2002 Q3 13F Filing 2026-03-31 2026-05-11
APG
API GROUP CORP
Industrials 0.79% 0.55% #22 24
Prev: #46
2.8
1,181,574 34.2%
P
S
4,634,929 $187,807,323 2025 Q4 13F Filing 2026-03-31 2026-05-11
PWR
QUANTA SVCS INC
Industrials 0.76% 0.48% #23 33
Prev: #56
2.8
58,288 21.3%
P
S
331,816 $182,173,674 2025 Q2 13F Filing 2026-03-31 2026-05-11
GEV
GE VERNOVA INC
Industrials 0.73% 0.48% #24 31
Prev: #55
2.3
21,372 12.0%
P
S
199,306 $173,974,371 2024 Q3 13F Filing 2026-03-31 2026-05-11
ARES
ARES MANAGEMENT...
Financial Services 0.72% 0.78% #25 2
Prev: #23
2.8
421,587 36.6%
P
S
1,572,787 $171,591,074 2021 Q3 13F Filing 2026-03-31 2026-05-11
RYTM
RHYTHM PHARMACE...
Healthcare 0.70% 0.57% #26 14
Prev: #40
3.3
661,965 52.2%
P
S
1,929,123 $167,775,827 2025 Q1 13F Filing 2026-03-31 2026-05-11
TSM
TAIWAN SEMICOND...
Technology 0.70% 0.56% #27 14
Prev: #41
2.3
47,309 10.6%
P
S
493,504 $166,779,716 2019 Q4 13F Filing 2026-03-31 2026-05-11
MRVL
MARVELL TECHNOL...
Technology 0.70% 0.69% #28 2
Prev: #30
0.8
-274,426 -14.1%
P
S
1,673,381 $165,748,387 2006 Q3 13F Filing 2026-03-31 2026-05-11
BE
BLOOM ENERGY CO...
Industrials 0.68% 0.41% #29 41
Prev: #70
0.8
46,276 4.0%
P
S
1,191,572 $161,446,090 2003 Q2 13F Filing 2026-03-31 2026-05-11
IOT
SAMSARA INC
Technology 0.67% 0.58% #30 8
Prev: #38
2.8
1,118,851 28.3%
P
S
5,072,821 $160,757,713 2021 Q4 13F Filing 2026-03-31 2026-05-11
AME
AMETEK INC
Industrials 0.67% 0.77% #31 7
Prev: #24
0.8
-154,384 -17.1%
P
S
745,832 $159,876,481 2003 Q4 13F Filing 2026-03-31 2026-05-11
PR
PERMIAN RESOURC...
Energy 0.67% 0.35% #32 61
Prev: #93
2.8
1,530,271 25.7%
P
S
7,481,457 $159,504,663 2023 Q3 13F Filing 2026-03-31 2026-05-11
DT
DYNATRACE INC
Technology 0.65% 0.61% #33 2
Prev: #35
2.8
852,886 25.4%
P
S
4,209,594 $155,670,786 2022 Q4 13F Filing 2026-03-31 2026-05-11
RVMD
REVOLUTION MEDI...
Healthcare 0.64% 0.94% #34 18
Prev: #16
0.3
-1,288,435 -45.3%
P
S
1,556,578 $151,377,191 2024 Q4 13F Filing 2026-03-31 2026-05-11
NTRA
NATERA INC
Healthcare 0.63% 0.68% #35 4
Prev: #31
2.3
40,037 5.6%
P
S
754,729 $150,938,268 2024 Q4 13F Filing 2026-03-31 2026-05-11
FN
FABRINET
Technology 0.62% 0.36% #36 53
Prev: #89
2.7
94,704 49.8%
P
S
284,874 $148,567,570 2023 Q2 13F Filing 2026-03-31 2026-05-11
ABVX
ABIVAX SA
Healthcare 0.62% 0.57% #37 2
Prev: #39
2.7
312,972 31.0%
P
S
1,322,938 $147,309,146 2025 Q4 13F Filing 2026-03-31 2026-05-11
NOW
SERVICENOW INC
Technology 0.61% 0.94% #38 21
Prev: #17
0.7
-82,616 -5.6%
P
S
1,394,187 $145,762,300 2013 Q4 13F Filing 2026-03-31 2026-05-11
FTI
TECHNIPFMC PLC
Energy 0.59% 0.36% #39 47
Prev: #86
0.7
81,328 4.2%
P
S
2,033,755 $140,593,483 2024 Q3 13F Filing 2026-03-31 2026-05-11
RCL
ROYAL CARIBBEAN...
Consumer Cyclical 0.58% 0.52% #40 10
Prev: #50
2.2
57,112 12.7%
P
S
505,765 $139,176,354 2003 Q2 13F Filing 2026-03-31 2026-05-11
HLT
HILTON WORLDWID...
Consumer Cyclical 0.58% 0.43% #41 24
Prev: #65
2.7
99,704 27.9%
P
S
457,425 $139,093,786 2002 Q2 13F Filing 2026-03-31 2026-05-11
V
VISA INC
Financial Services 0.58% 0.88% #42 23
Prev: #19
0.2
-147,378 -24.4%
P
S
456,548 $137,987,039 2008 Q1 13F Filing 2026-03-31 2026-05-11
COR
CENCORA INC
Healthcare 0.58% 0.45% #43 18
Prev: #61
2.7
117,694 36.9%
P
S
436,909 $137,250,518 2025 Q1 13F Filing 2026-03-31 2026-05-11
ITT
ITT INC
Industrials 0.56% 0.42% #44 23
Prev: #67
2.2
115,863 19.7%
P
S
703,309 $134,001,464 2005 Q4 13F Filing 2026-03-31 2026-05-11
CELH
CELSIUS HLDGS I...
Consumer Defensive 0.56% 0.29% #45 71
Prev: #116
3.2
2,224,696 144.1%
P
S
3,768,911 $133,720,962 2025 Q4 13F Filing 2026-03-31 2026-05-11
NXT
NEXTPOWER INC
Technology 0.56% 0.40% #46 31
Prev: #77
0.7
17,046 1.6%
P
S
1,107,346 $133,490,560 2023 Q1 13F Filing 2026-03-31 2026-05-11
LNG
CHENIERE ENERGY...
Energy 0.55% #47
Prev: #—
3.7
459,044
NEW
459,044 $130,258,215 2026 Q1 13F Filing 2026-03-31 2026-05-11
AS
AMER SPORTS INC
Consumer Cyclical 0.54% #48
Prev: #—
3.7
3,937,521
NEW
3,937,521 $129,623,185 2026 Q1 13F Filing 2026-03-31 2026-05-11
RRX
REGAL REXNORD C...
Industrials 0.54% 0.52% #49
Prev: #49
0.2
-211,383 -23.7%
P
S
681,717 $127,658,325 2023 Q4 13F Filing 2026-03-31 2026-05-11
MSCI
MSCI INC
Financial Services 0.53% 0.50% #50 3
Prev: #53
2.2
25,972 12.5%
P
S
233,764 $126,000,886 2009 Q1 13F Filing 2026-03-31 2026-05-11
Showing 1-50 of 287 holdings

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