Renaissance Technologies (RenTech)'s AMPH Position Overview
Renaissance Technologies (RenTech) (via Renaissance Technologies LLC) currently holds 553,900 shares of Amphastar Pharmaceuticals, Inc. (AMPH) worth $10.85 M, representing 0.02% of the portfolio. First purchased in 2015-Q1, this long-term strategic position has been held for 40 quarters.
Based on 13F filings, Renaissance Technologies (RenTech) has maintained a strategic position in AMPH, demonstrating sustained confidence in this investment. Largest addition occurred in Q2 2015, adding 193,626 shares. Largest reduction occurred in Q2 2020, reducing 227,300 shares.
Analysis based on 13F filings available since 2013 Q2
Renaissance Technologies (RenTech)'s Amphastar Pharmaceuticals (AMPH) Holding Value Over Time
Track share changes against reported price movement
Quarterly Amphastar Pharmaceuticals (AMPH) Trades by Renaissance Technologies (RenTech)
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q1 2026 | +9,200 | Add 1.69% | 553,900 | $19.59 |
| Q4 2025 | -42,200 | Reduce 7.19% | 544,700 | $26.78 |
| Q3 2025 | +10,400 | Add 1.80% | 586,900 | $26.65 |
| Q2 2025 | +81,500 | Add 16.46% | 576,500 | $22.96 |
| Q1 2025 | -30,500 | Reduce 5.80% | 495,000 | $28.99 |
| Q4 2024 | +36,100 | Add 7.38% | 525,500 | $37.13 |
| Q3 2024 | -48,300 | Reduce 8.98% | 489,400 | $48.53 |
| Q2 2024 | -61,400 | Reduce 10.25% | 537,700 | $40.00 |
| Q1 2024 | -42,800 | Reduce 6.67% | 599,100 | $43.91 |
| Q4 2023 | +38,800 | Add 6.43% | 641,900 | $61.85 |
| Q3 2023 | +110,517 | Add 22.44% | 603,100 | $45.99 |
| Q2 2023 | -4,217 | Reduce 0.85% | 492,583 | $0.06 |
| Q1 2023 | +49,400 | Add 11.04% | 496,800 | $0.04 |
| Q4 2022 | +13,600 | Add 3.14% | 447,400 | $0.03 |
| Q3 2022 | +26,900 | Add 6.61% | 433,800 | $28.10 |
| Q2 2022 | +98,200 | Add 31.81% | 406,900 | $34.79 |
| Q1 2022 | +18,900 | Add 6.52% | 308,700 | $35.90 |
| Q4 2021 | +14,100 | Add 5.11% | 289,800 | $23.29 |
| Q3 2021 | +28,600 | Add 11.57% | 275,700 | $19.01 |
| Q2 2021 | +21,500 | Add 9.53% | 247,100 | $20.16 |
| Q1 2021 | -87,000 | Reduce 27.83% | 225,600 | $18.32 |
| Q4 2020 | -65,700 | Reduce 17.37% | 312,600 | $20.11 |
| Q3 2020 | -133,000 | Reduce 26.01% | 378,300 | $18.75 |
| Q2 2020 | -227,300 | Reduce 30.77% | 511,300 | $22.46 |
| Q1 2020 | -94,400 | Reduce 11.33% | 738,600 | $14.84 |
| Q4 2019 | +102,300 | Add 14.00% | 833,000 | $19.29 |
| Q3 2019 | +142,700 | Add 24.27% | 730,700 | $19.83 |
| Q2 2019 | +146,400 | Add 33.15% | 588,000 | $21.11 |
| Q1 2019 | +131,500 | Add 42.41% | 441,600 | $20.43 |
| Q4 2018 | +124,000 | Add 66.63% | 310,100 | $19.90 |
| Q3 2018 | +95,000 | Add 104.28% | 186,100 | $19.24 |
| Q2 2018 | +39,500 | Add 76.55% | 91,100 | $15.26 |
| Q1 2018 | +39,800 | Add 337.29% | 51,600 | $18.76 |
| Q4 2017 | +11,800 | New Buy | 11,800 | $19.24 |
| Q4 2016 | -21,900 | Sold Out | 0 | $0.00 |
| Q3 2016 | +21,900 | New Buy | 21,900 | $18.95 |
| Q4 2015 | -131,000 | Sold Out | 0 | $0.00 |
| Q3 2015 | -186,006 | Reduce 58.68% | 131,000 | $11.69 |
| Q2 2015 | +193,626 | Add 156.93% | 317,006 | $17.58 |
| Q1 2015 | +123,380 | New Buy | 123,380 | $14.96 |
Renaissance Technologies (RenTech)'s Amphastar Pharmaceuticals Investment FAQs
Renaissance Technologies (RenTech) first purchased Amphastar Pharmaceuticals, Inc. (AMPH) in Q1 2015, acquiring 123,380 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Renaissance Technologies (RenTech) has held Amphastar Pharmaceuticals, Inc. (AMPH) for 40 quarters since Q1 2015.
Renaissance Technologies (RenTech)'s largest addition to Amphastar Pharmaceuticals, Inc. (AMPH) was in Q2 2015, adding 317,006 shares worth $5.57 M.
According to the latest 13F filing for Q1 2026, Renaissance Technologies (RenTech)'s firm, Renaissance Technologies LLC, owns 553,900 shares of Amphastar Pharmaceuticals, Inc. (AMPH), valued at approximately $10.85 M.
As of the Q1 2026 filing, Amphastar Pharmaceuticals, Inc. (AMPH) represents approximately 0.02% of Renaissance Technologies (RenTech)'s publicly disclosed stock portfolio, making it one of their key holdings.
Renaissance Technologies (RenTech)'s peak holding in Amphastar Pharmaceuticals, Inc. (AMPH) was 833,000 shares, as reported at the end of Q4 2019.