WESTFIELD CAPITAL MANAGEMENT CO LP
13F portfolio as of Jun 30, 2026 · due to the SEC by Aug 14, 2026
- Filer
- WESTFIELD CAPITAL MANAGEMENT CO LP
- SEC CIK
- 0001177719 · 13F filings on EDGAR ↗
- Latest 13F
- Quarter ended Jun 30, 2026
- Securities held
- 278
- Total value
- $30.61B
At Jun 30, 2026, WESTFIELD CAPITAL MANAGEMENT CO LP reported 278 securities worth $30.61B on Form 13F. Their largest reported line was NVDA, at $1.62B.
Showing the 10 largest of 278 securities. Totals above cover the whole portfolio. Position detail is stored for the largest 174, covering 95.0% of portfolio value.
10 largest positions
Ranked by value across position types · quarter ended Jun 30, 2026
| # | Holding | Value | Shares or principal |
|---|---|---|---|
| 1 | NVDA | $1.62B | 8.1M |
| 2 | GOOGL | $1.34B | 3.7M |
| 3 | ASND | $1.28B | 4.8M |
| 4 | AXON | $836.14M | 1.5M |
| 5 | FTAI | $794.61M | 2.9M |
| 6 | AAPL | $744.75M | 2.6M |
| 7 | FIX | $704.45M | 355.4K |
| 8 | AVGO | $587.98M | 1.6M |
| 9 | MSFT | $527.56M | 1.4M |
| 10 | HWM | $516.61M | 1.9M |
What this covers
Form 13F covers long positions in US-listed equities and listed options. Short positions, cash, bonds, foreign-listed holdings and most derivatives are outside it, so this is a partial view of the manager rather than their portfolio. Managers file within 45 days of quarter end, so holdings are a snapshot of Jun 30, 2026 that reached the public later. The figures are self-reported by the filer. Where a manager filed an amendment, the amended report is the one used here, and a manager filing through several entities is aggregated into one book.
quarters of WESTFIELD CAPITAL MANAGEMENT CO LP on file
This page shows one quarter. The full history, every position rather than the ten largest, portfolio weights, and each position’s change from the prior quarter are available through the API and the research app.
Programmatic access
Everything on this page is served by the Distill API and by the MCP server at mcp.distillmarkets.com. A free key is issued at sign-up with no card; the full reference is in the docs.
- This quarter: whole-book totals and the largest positions (every position, with weights, on Analyst)
- curlcurl -H "X-Api-Key: $DISTILL_API_KEY" \https://api.distillmarkets.com/api/v1/sec/managers/0001177719
MCP tool:
get_manager_portfolio holder_key=0001177719 - Any earlier quarter on file
- curlcurl -H "X-Api-Key: $DISTILL_API_KEY" \https://api.distillmarkets.com/api/v1/sec/managers/0001177719?period=YYYY-MM-DD
MCP tool:
get_manager_portfolio holder_key=0001177719 period=YYYY-MM-DD
Not investment advice. Figures are shown as filed with the SEC. A 13F reports what a manager held at quarter end, not what they hold now.