ARROWSTREET CAPITAL, LIMITED PARTNERSHIP
Position in AMPH — Amphastar Pharmaceuticals, Inc.
CIK 1164508
BOSTON, MA
Position in AMPH
as of Mar 31, 2026
· filed May 14, 2026
Position Value
$6,372,450
-$8,608,978 QoQ
Shares Held
325,291
-41.9% QoQ
Ownership
0.738%
of shares outstanding
% of Portfolio
0.00%
of 13F equity value
Holder Rank
—
not a current holder
Holding Since
Mar 2021
16 quarters on record
Voting authority
Sole 100.ToString("F0")%
Shared 0.ToString("F0")%
None 0.ToString("F0")%
Common Shares in AMPH Over Time
Shares Held
Position Value (USD)
Position in Drug Manufacturers - Specialty & Generic
Healthcare · as of Mar 31, 2026ARROWSTREET CAPITAL, LIMITED PARTNERSHIP holds $805,226,112 across 23 Drug Manufacturers - Specialty & Generic names. AMPH ranks #14 (0.8% of the industry book) .
| # | Ticker | Company | Shares | Value (USD) | Open |
|---|---|---|---|---|---|
| 1 | ZTS |
Zoetis Inc.
|
1,975,559 | $233,530,829 | |
| 2 | HLN |
Haleon plc
|
14,674,518 | $146,891,925 | |
| 3 | VTRS |
Viatris Inc
|
8,545,196 | $115,445,597 | |
| 4 | INDV |
Indivior Pharmaceuticals, Inc.
|
2,323,264 | $70,813,086 | |
| 5 | TAK |
Takeda Pharmaceutical Co Ltd
|
3,116,311 | $57,714,079 | |
| 6 | ANIP |
Ani Pharmaceuticals Inc
|
564,360 | $43,399,284 | |
| 7 | KNSA |
Kiniksa Pharmaceuticals International, plc
|
892,666 | $42,981,867 | |
| 8 | COLL |
Collegium Pharmaceutical, Inc
|
703,528 | $23,265,670 |
All Filings in AMPH
Export CSV
16 filing rows on record
| Report Date | Value (USD) | Shares | Type | Discretion | Filed | |
|---|---|---|---|---|---|---|
| 2026-03-31 | $6,372,450 | 325,291 | Shares | Defined | 2026-05-14 | |
| 2025-12-31 | $14,981,428 | 559,426 | Shares | Defined | 2026-02-13 | |
| 2025-09-30 | $10,455,061 | 392,310 | Shares | Defined | 2025-11-13 | |
| 2025-06-30 | $1,865,247 | 81,239 | Shares | Defined | 2025-08-13 | |
| 2024-03-31 | $989,687 | 22,539 | Shares | Defined | 2024-05-15 | |
| 2023-09-30 | $1,298,297 | 28,230 | Shares | Defined | 2023-11-14 | |
| 2023-06-30 | $1,672,319 | 29,099 | Shares | Defined | 2023-08-14 | |
| 2023-03-31 | $2,785,275 | 74,274 | Shares | Defined | 2023-05-15 | |
| 2022-12-31 | $4,652,440 | 166,040 | Shares | Defined | 2023-02-14 | |
| 2022-09-30 | $5,649,926 | 201,065 | Shares | Defined | 2022-11-14 | |
| 2022-06-30 | $10,599,538 | 304,672 | Shares | Defined | 2022-08-15 | |
| 2022-03-31 | $14,057,901 | 391,585 | Shares | Defined | 2022-05-13 | |
| 2021-12-31 | $9,689,781 | 416,049 | Shares | Defined | 2022-02-14 | |
| 2021-09-30 | $3,772,952 | 198,472 | Shares | Defined | 2021-11-12 | |
| 2021-06-30 | $2,941,706 | 145,918 | Shares | Defined | 2021-08-13 | |
| 2021-03-31 | $1,023,520 | 55,869 | Shares | Defined | 2021-05-14 | |
| No filing history on record for this holder in this stock. | ||||||