WESTFIELD CAPITAL MANAGEMENT CO LP

CIK 0001177719 · Q2 2026

13F Equity AUM

$30.6B

+28.4% QoQ

Positions

278

+28 QoQ

AUM Rank

#257

Top 3%

Skill Alpha (FF)

-0.0%/yr^ns

No Clear Edge

Rank #2,832 · Top 34%

vs S&P +1.5%/yr (unadj.)

Quarters Tracked

~13 years

Portfolio Concentration

Top 5: 19.2%Top 10: 29.2%Top 20: 40.4%

NVDA5.3%

GOOGL4.4%

ASCENDIS PHARMA A/S4.2%

AXON2.7%

FTAIN2.6%

AAPL2.4%

FIX2.3%

AVGO1.9%

MSFT1.7%

HWM1.7%

Others (268)70.8%

HHI (Herfindahl-Hirschman Index) measures portfolio concentration. Low (<1500) = diversified, Moderate (1500-2500), High (>2500) = concentrated bets.

Sector Allocation

Technology34.0%

Industrials22.1%

Healthcare11.7%

Communication Services7.2%

Financial Services7.0%

Consumer Cyclical7.0%

Unclassified5.3%

Other5.9%

Portfolio weight by GICS sector based on latest 13F filing. Sectors below 2% are grouped as “Other.”

Position Sizing

Positions: 278Median: 0.20%Avg: 0.36%

0–0.5%

224(37.5%)

0.5–1%

39(26.5%)

1–3%

12(22.2%)

3–5%

2(8.6%)

5%+

1(5.3%)

Count of positions per weight bucket — (%) = combined portfolio weight

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Portfolio Overlap

Shared: 0Unique: 278vs 20 funds

0%Low

278

Fund positions

Consensus CUSIPs

Jaccard similarity of this fund’s portfolio vs the consensus of top 20 funds by AUM. Low (<15%) = contrarian, Moderate (15-40%), High (>40%) = follows the crowd.

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Position Changes This Quarter

New69Increased98Decreased103Exited41

New Positions

ASCENDIS PHARMA A/S4.2%

+4.8M

CRS0.6%

+314K

PTCT0.5%

+2.0M

LRCX0.4%

+286K

ASML0.4%

+57K

SNDK0.4%

+49K

NPO0.3%

+287K

FROG0.3%

+1.1M

FORGENT POWER SOLUTI…0.3%

+1.4M

RBRK0.3%

+937K

Increased

LTH0.8%

+2.8M(+88%)

AS0.7%

+2.4M(+61%)

PL0.4%

+1.8M(+109%)

NVDA5.3%

+1.8M(+28%)

GOOGL4.4%

+1.7M(+85%)

CELH0.5%

+1.6M(+41%)

APG0.8%

+1.5M(+33%)

CSX0.5%

+1.5M(+90%)

KEY0.5%

+1.3M(+25%)

GILD0.5%

+1.3M(+4724%)

Decreased

RIOT0.1%

-2,486,076(-71%)

PR0.3%

-1,724,569(-23%)

NFLX0.1%

-1,679,161(-85%)

FITB0.1%

-1,674,407(-70%)

MRVL0.0%

-1,660,188(-99%)

AMZN0.7%

-1,419,848(-62%)

BRZE0.2%

-1,356,374(-34%)

LEGN0.4%

-1,333,412(-23%)

BE0.0%

-1,181,002(-99%)

PCVX0.5%

-1,173,710(-32%)

Exited

-4,813,440

-1,458,711

-1,563,146

-674,557

-1,369,108

-298,542

-429,500

-300,962

-427,919

3M4

-341,229

Quarter-over-quarter changes compared to prior 13F filing. New = first appearance; Exited = no longer held.

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Holdings

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