WESTFIELD CAPITAL MANAGEMENT CO LP
Position in ADPT — Adaptive Biotechnologies Corp
CIK 1177719
BOSTON, MA
Position in ADPT
as of Mar 31, 2026
· filed May 11, 2026
Position Value
$75,461,645
+$9,519,434 QoQ
Shares Held
5,436,718
+33.9% QoQ
Ownership
3.40%
of shares outstanding
% of Portfolio
0.32%
of 13F equity value
Holder Rank
—
not a current holder
Holding Since
Dec 2025
2 quarters on record
Voting authority
Sole 92.14172962437999.ToString("F0")%
Shared 0.ToString("F0")%
None 7.8582703756199965.ToString("F0")%
Common Shares in ADPT Over Time
Shares Held
Position Value (USD)
Position in Diagnostics & Research
Healthcare · as of Mar 31, 2026WESTFIELD CAPITAL MANAGEMENT CO LP holds $572,134,101 across 8 Diagnostics & Research names. ADPT ranks #4 (13.2% of the industry book) .
| # | Ticker | Company | Shares | Value (USD) | Open |
|---|---|---|---|---|---|
| 1 | NTRA |
Natera, Inc.
|
754,729 | $150,938,252 | |
| 2 | GH |
Guardant Health, Inc.
|
1,362,539 | $125,857,727 | |
| 3 | WGS |
GeneDx Holdings Corp.
|
1,369,108 | $87,924,115 | |
| 4 | ADPT |
Adaptive Biotechnologies Corp
This page
|
5,436,718 | $75,461,645 | |
| 5 | IDXX |
Idexx Laboratories Inc /De
|
132,860 | $74,652,705 | |
| 6 | RDNT |
RadNet, Inc.
|
531,893 | $29,727,499 | |
| 7 | DHR |
Danaher Corp /De/
|
110,492 | $20,949,283 | |
| 8 | TMO |
Thermo Fisher Scientific Inc.
|
13,474 | $6,622,875 |
All Filings in ADPT
Export CSV
2 filing rows on record
| Report Date | Value (USD) | Shares | Type | Discretion | Filed | |
|---|---|---|---|---|---|---|
| 2026-03-31 | $75,461,645 | 5,436,718 | Shares | Sole | 2026-05-11 | |
| 2025-12-31 | $65,942,211 | 4,060,481 | Shares | Sole | 2026-02-11 | |
| No filing history on record for this holder in this stock. | ||||||