Amphastar Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US03209R1032

SecurityAMPH / Amphastar Pharmaceuticals, Inc.
InstitutionBessemer Group Inc
Latest Disclosed Ownership122,046 shares
Latest Disclosed Value $ 2,391
Bessemer Group Inc reports 0.96% increase in ownership of AMPH / Amphastar Pharmaceuticals, Inc.

On May 6, 2026 - Bessemer Group Inc filed a 13F-HR form disclosing ownership of 122,046 shares of Amphastar Pharmaceuticals, Inc. (US:AMPH) valued at $2,390,881 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 5, 2026 disclosing 120,890 shares of Amphastar Pharmaceuticals, Inc.. This represents a change in shares of 0.96% during the quarter. The current value of the position is $2,211,474 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-06 2026-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 122,046 1,156 0.96 2 -33.33 0.0038
2026-02-05 2025-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 120,890 120,747 84,438.46 3 0.0050
2025-11-05 2025-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 143 -57 -28.50 0 0.0000
2025-08-01 2025-06-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 200 -361 -64.35 0 0.0000
2025-04-23 2025-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 561 -488,069 -99.89 0 -100.00 0.0000
2025-02-13 2024-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 488,630 11,609 2.43 18 -21.74 0.0296
2024-11-12 2024-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 477,021 10,793 2.31 23 27.78 0.0381
2024-08-13 2024-06-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 466,228 70,287 17.75 19 5.88 0.0329
2024-08-13 2024-03-31 13F/A-1 AMPHASTAR PHARMACEUTICALS SC 03209R103 395,941 69,968 21.46 17 -15.00 0.0314
2024-05-13 2024-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 395,941 69,968 17 0.0314
2024-02-09 2023-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 325,973 177,829 120.04 20 233.33 0.0393
2023-11-13 2023-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 148,144 147,824 46,195.00 7 0.0150
2023-08-10 2023-06-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 320 182 131.88 0 0.0000
2023-05-10 2023-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 138 24 21.05 0 0.0000
2023-02-13 2022-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 114 0 0.00 0 -100.00 0.0000
2022-11-09 2022-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 114 -48 -29.63 3 -50.00 0.0000
2022-08-10 2022-06-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 162 0 0.00 6 0.00 0.0000
2022-05-12 2022-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 162 162 6 0.0000
2020-11-12 2020-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 0 -111,600 -100.00 0 -100.00
2020-08-05 2020-06-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 111,600 0 0.00 2,507 51.39 0.0079
2020-04-30 2020-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 111,600 900 0.81 1,656 -22.44 0.0067
2020-02-04 2019-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 110,700 5,600 5.33 2,135 2.45 0.0069
2019-11-07 2019-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 105,100 6,600 6.70 2,084 0.24 0.0074
2019-07-19 2019-06-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 98,500 -1,400 -1.40 2,079 1.86 0.0070
2019-05-13 2019-03-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 99,900 29,400 41.70 2,041 45.47 0.0078
2019-05-21 2018-12-31 13F/A-1 AMPHASTAR PHARMACEUTICALS SC 03209R103 70,500 38,300 118.94 1,403 126.29 0.0061
2019-02-12 2018-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 70,500 38,300 1,403 0.0061
2018-11-06 2018-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 32,200 32,200 620 0.0023
2017-02-07 2016-12-31 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 0 -9,400 -100.00 0 -100.00
2016-11-10 2016-09-30 13F AMPHASTAR PHARMACEUTICALS SC 03209R103 9,400 9,400 178 0.0009
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.