AMPH
Amphastar Pharmaceuticals, Inc. · Healthcare · Drug Manufacturers - Specialty & Generic
Momentum inputs (comparable managers):
holder breadth -7.7% ·
share flow +18.9% ·
net new positions -8.3%
· formula
Concentrated accumulation: rising shares among fewer holders
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q1 2025
| Quarter | Holders | Δ | Shares | Reported value | New | Exits |
|---|---|---|---|---|---|---|
| Q3 2026 | 1 | 0 | 15.22K | $392,725 | n/a | n/a |
| Q2 2026 | 77 | -4 | 22.11M | $440.50M | +3 | −7 |
| Q1 2026 | 84 | -10 | 23.72M | $457.46M | +4 | −14 |
| Q4 2025 | 94 | -1 | 25.83M | $677.54M | n/a | −1 |
| Q3 2025 | 19 | 0 | 15.63M | $416.60M | n/a | n/a |
| Q2 2025 | 16 | +1 | 14.08M | $323.35M | +1 | n/a |
| Q1 2025 | 12 | -1 | 5.84M | $169.25M | n/a | −1 |
| Q4 2024 | 13 | 0 | 4.91M | $182.39M | n/a | n/a |
| Q3 2024 | 12 | +2 | 3.20M | $155.33M | +2 | n/a |
| Q2 2024 | 10 | n/a | 3.67M | $146.92M | n/a | n/a |
| # | Manager | Shares | Δ shares | Value | Their weight | Held | ||
|---|---|---|---|---|---|---|---|---|
| 1 | State Street Global Advisors ✦ (passive) | 1.60M | +0.5% | $46.52M | 0.0% | ▲ Add | 2 | SEC ↗ |
| 2 | Marshall Wace ✦ | 1.03M | +69.5% | $29.91M | 0.0% | ▲ Add | 4 | SEC ↗ ×2 |
| 3 | Geode Capital Management ✦ (passive) | 955.08K | +4.3% | $27.69M | 0.0% | ▲ Add | 4 | SEC ↗ ×2 |
| 4 | Millennium Management ✦ | 868.55K | +238.5% | $25.18M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 5 | T. Rowe Price ✦ | 541.22K | -4.5% | $15.69M | 0.0% | ▼ Trim | 4 | SEC ↗ ×2 |
| 6 | Renaissance Technologies ✦ | 495.00K | -5.8% | $14.35M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 7 | Citadel Advisors ✦ | 155.98K | +11.1% | $4.52M | 0.0% | ▲ Add | 4 | SEC ↗ ×2 |
| 8 | Two Sigma Investments ✦ | 75.33K | -23.3% | $2.18M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 9 | AQR Capital Management ✦ | 53.64K | +82.0% | $1.55M | 0.0% | ▲ Add | 4 | SEC ↗ ×4 |
| 10 | D. E. Shaw & Co. ✦ | 29.19K | -75.4% | $846,160 | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 11 | Wellington Management ✦ | 16.91K | -4.9% | $490,308 | 0.0% | ▼ Trim | 3 | SEC ↗ ×4 |
| 12 | Gotham Asset Management ✦ | 10.87K | -61.8% | $315,121 | 0.0% | ▼ Trim | 4 | SEC ↗ |
“Their weight” = the position's share of that manager's reported 13F equity value: the conviction measure. ✦ = curated manager.
New buyers
| No new tracked buyers this quarter. |
Exited
| Point72 Asset Management | $341,596 | was 0.0% |
Full-market context: across ALL 13F filers (SEC structured data, Q1 2026): 212 holders, 31.98M shares, $604.53M reported. This is a different, older period than the tracked-universe figures above and the two are never mixed.
What else this security's tracked holders most often hold: shared-ownership counts, not fundamental relationships.
Open-market purchases (P)
No open-market insider purchases in our coverage window.
Open-market sales (S)
Officer, Director · 4.14K sh · $103,475
Officer · 10.00K sh · $239,404
Officer · 3.19K sh · $75,306
Director · 7.97K sh · $161,852
Officer, Director · 8.18K sh · $183,886
Awards, exercises and tax withholding are never counted as buys or sales here. Methodology