WESTFIELD CAPITAL MANAGEMENT CO LP

CIK

1177719

City

BOSTON

State / Country

Stock

MSCI — MSCI Inc.

Top Portfolio Positions

243 positions · $23,810,970,015 total · as of Mar 31, 2026

Ticker	Company	Shares	Value (USD)	% of Portfolio
NVDA	Nvidia Corp Technology	6,317,039	$1,101,691,601	4.63%
ASND	Ascendis Pharma A/S Healthcare	4,813,440	$1,100,978,131	4.62%
FIX	Comfort Systems USA Inc Industrials	620,915	$856,235,575	3.60%
AAPL	Apple Inc. Technology	3,133,113	$795,152,748	3.34%
FTAI	FTAI Aviation Ltd. Industrials	2,848,227	$697,815,615	2.93%
MSFT	Microsoft Corp Technology	1,649,513	$610,600,227	2.56%
GOOGL	Alphabet Inc. Communication Services	2,026,744	$582,810,504	2.45%
HWM	Howmet Aerospace Inc. Industrials	2,289,697	$527,683,570	2.22%
VRT	Vertiv Holdings Co Industrials	1,921,696	$481,538,583	2.02%
AMZN	Amazon Com Inc Consumer Cyclical	2,279,654	$474,783,538	1.99%

25 quarters · across all stocks

25 quarters on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$126,001,133	233,764	+12.5%	Shares	Sole	2026-05-11
2025-12-31	$119,216,504	207,792	+18.5%	Shares	Sole	2026-02-11
2025-09-30	$99,493,641	175,347	+21.5%	Shares	Sole	2025-11-12
2025-06-30	$83,258,186	144,360	-17.8%	Shares	Sole	2025-08-12
2025-03-31	$99,322,158	175,636	+17.9%	Shares	Sole	2025-05-09
2024-12-31	$89,365,489	148,940	-3.2%	Shares	Sole	2025-02-11
2024-09-30	$89,737,992	153,943	+20.2%	Shares	Sole	2024-11-12
2024-06-30	$61,709,284	128,094	-14.9%	Shares	Sole	2024-08-14
2024-03-31	$84,357,813	150,518	+1.6%	Shares	Sole	2024-05-10
2023-12-31	$83,785,774	148,123	-7.8%	Shares	Sole	2024-02-09
2023-09-30	$82,441,181	160,679	-19.1%	Shares	Sole	2023-11-13
2023-06-30	$93,254,493	198,714	+18.8%	Shares	Sole	2023-08-11
2023-03-31	$93,650,688	167,326	-0.8%	Shares	Sole	2023-05-12
2022-12-31	$78,475,574	168,703	+1.2%	Shares	Sole	2023-02-13
2022-09-30	$70,315,767	166,708	+13.0%	Shares	Sole	2022-11-14
2022-06-30	$60,792,125	147,500	+10.2%	Shares	Sole	2022-08-12
2022-03-31	$67,297,413	133,824	+5.8%	Shares	Sole	2022-05-16
2021-12-31	$77,463,009	126,431	-2.5%	Shares	Sole	2022-02-10
2021-09-30	$78,850,597	129,616	-15.8%	Shares	Sole	2021-11-12
2021-06-30	$82,093,786	153,999	-12.2%	Shares	Sole	2021-08-10
2021-03-31	$73,533,326	175,380	+0.9%	Shares	Sole	2021-05-14
2020-12-31	$77,614,505	173,817	+11.5%	Shares	Sole	2021-02-12
2020-09-30	$55,604,519	155,851	+14.6%	Shares	Sole	2020-11-13
2020-06-30	$45,409,534	136,030	-24.7%	Shares	Sole	2020-08-13
2020-03-31	$52,222,296	180,725	—	Shares	Sole	2020-05-14
No 13F history on record for this holder in this stock.