GW&K Investment Management, LLC
Position in PHAT — Phathom Pharmaceuticals, Inc.
CIK 1082917
BOSTON, MA
Position in PHAT
as of Mar 31, 2026
· filed May 13, 2026
Position Value
$15,788,520
-$5,889,268 QoQ
Shares Held
1,421,109
+8.8% QoQ
Ownership
1.78%
of shares outstanding
% of Portfolio
0.14%
of 13F equity value
Holder Rank
—
not a current holder
Holding Since
Mar 2021
21 quarters on record
Voting authority
Sole 100%
Shared 0%
None 0%
Common Shares in PHAT Over Time
Shares Held
Position Value (USD)
Position in Biotechnology
Healthcare · as of Mar 31, 2026GW&K Investment Management, LLC holds $699,704,251 across 25 Biotechnology names. PHAT ranks #13 (2.3% of the industry book) .
| # | Ticker | Company | Shares | Value (USD) | Open |
|---|---|---|---|---|---|
| 1 | INSM |
INSMED Inc
|
623,048 | $101,880,808 | |
| 2 | HALO |
Halozyme Therapeutics, Inc.
|
1,393,875 | $90,086,140 | |
| 3 | BBIO |
BridgeBio Pharma, Inc.
|
962,643 | $71,485,868 | |
| 4 | JAZZ |
Jazz Pharmaceuticals plc
|
371,098 | $70,156,076 | |
| 5 | CRNX |
Crinetics Pharmaceuticals, Inc.
|
1,618,686 | $58,790,674 | |
| 6 | IONS |
Ionis Pharmaceuticals Inc
|
779,349 | $58,521,315 | |
| 7 | VCEL |
Vericel Corp
|
1,616,855 | $52,014,225 | |
| 8 | AGIO |
Agios Pharmaceuticals, Inc.
|
1,214,901 | $41,100,100 |
All Filings in PHAT
Export CSV
21 filing rows on record
| Report Date | Value (USD) | Shares | Type | Discretion | Filed | |
|---|---|---|---|---|---|---|
| 2026-03-31 | $15,788,520 | 1,421,109 | Shares | Sole | 2026-05-13 | |
| 2025-12-31 | $21,677,788 | 1,306,678 | Shares | Sole | 2026-02-11 | |
| 2025-09-30 | $13,468,764 | 1,144,330 | Shares | Sole | 2025-11-12 | |
| 2025-06-30 | $10,054,846 | 1,048,472 | Shares | Sole | 2025-08-11 | |
| 2025-03-31 | $6,924,011 | 1,104,308 | Shares | Sole | 2025-05-05 | |
| 2024-12-31 | $8,954,776 | 1,102,805 | Shares | Sole | 2025-02-05 | |
| 2024-09-30 | $20,359,580 | 1,126,083 | Shares | Sole | 2024-11-07 | |
| 2024-06-30 | $6,184,562 | 600,443 | Shares | Sole | 2024-08-12 | |
| 2024-03-31 | $6,032,436 | 568,026 | Shares | Sole | 2024-05-08 | |
| 2023-12-31 | $5,126,403 | 561,490 | Shares | Sole | 2024-02-09 | |
| 2023-09-30 | $5,988,156 | 577,450 | Shares | Sole | 2023-11-09 | |
| 2023-06-30 | $8,482,996 | 592,388 | Shares | Sole | 2023-08-09 | |
| 2023-03-31 | $4,275,774 | 598,848 | Shares | Sole | 2023-05-09 | |
| 2022-12-31 | $6,666,441 | 594,157 | Shares | Sole | 2023-02-10 | |
| 2022-09-30 | $6,572,201 | 593,159 | Shares | Sole | 2022-11-09 | |
| 2022-06-30 | $4,164,718 | 493,450 | Shares | Sole | 2022-08-09 | |
| 2022-03-31 | $6,527,927 | 479,642 | Shares | Sole | 2022-05-09 | |
| 2021-12-31 | $7,544,467 | 383,552 | Shares | Sole | 2022-02-11 | |
| 2021-09-30 | $7,220,028 | 224,923 | Shares | Sole | 2021-11-10 | |
| 2021-06-30 | $7,765,799 | 229,418 | Shares | Sole | 2021-08-10 | |
| 2021-03-31 | $7,493,896 | 199,518 | Shares | Sole | 2021-05-11 | |
| No filing history on record for this holder in this stock. | ||||||