Amphastar Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US03209R1032

SecurityAMPH / Amphastar Pharmaceuticals, Inc.
InstitutionUs Bancorp \de\
Latest Disclosed Ownership318 shares
Latest Disclosed Value $ 6,230
Us Bancorp \de\ reports 60.55% decrease in ownership of AMPH / Amphastar Pharmaceuticals, Inc.

On May 14, 2026 - Us Bancorp \de\ filed a 13F-HR form disclosing ownership of 318 shares of Amphastar Pharmaceuticals, Inc. (US:AMPH) valued at $6,230 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 30, 2026 disclosing 806 shares of Amphastar Pharmaceuticals, Inc.. This represents a change in shares of -60.55% during the quarter. The current value of the position is $5,947 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)
2026-05-14 2026-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 318 -488 -60.55 6 -71.43 0.0000
2026-01-30 2025-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 806 -44 -5.18 22 -4.55 0.0000
2025-11-12 2025-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 850 419 97.22 23 144.44 0.0000
2025-07-24 2025-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 431 29 7.21 10 -18.18 0.0000
2025-05-08 2025-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 402 -446 -52.59 12 -64.52 0.0000
2025-02-05 2024-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 848 -6,520 -88.49 31 -91.32 0.0000
2024-10-28 2024-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 7,368 -6,986 -48.67 358 -37.80 0.0005
2024-08-07 2024-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 14,354 -2,702 -15.84 574 -23.26 0.0008
2024-05-08 2024-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 17,056 -4,192 -19.73 749 -43.07 0.0010
2024-02-09 2023-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 21,248 20,475 2,648.77 1,314 3,654.29 0.0019
2023-11-03 2023-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 773 -308 -28.49 36 -43.55 0.0001
2023-08-10 2023-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 1,081 -2,277 -67.81 62 -50.40 0.0001
2023-05-09 2023-03-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 3,358 58 1.76 126 35.87 0.0002
2023-02-13 2022-12-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 3,300 808 32.42 92 31.43 0.0002
2022-10-27 2022-09-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 2,492 469 23.18 70 0.00 0.0001
2022-08-01 2022-06-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 2,023 670 49.52 70 42.86 0.0001
2022-05-11 2022-03-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,353 43 3.28 49 58.06 0.0001
2022-02-11 2021-12-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,310 149 12.83 31 40.91 0.0000
2021-11-10 2021-09-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,161 0 0.00 22 -4.35 0.0000
2021-08-05 2021-06-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,161 0 0.00 23 9.52 0.0000
2021-04-28 2021-03-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,161 -31 -2.60 21 -12.50 0.0000
2021-02-04 2020-12-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,192 0 0.00 24 4.35 0.0001
2020-11-10 2020-09-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,192 -2,102 -63.81 23 -68.92 0.0001
2020-08-07 2020-06-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 3,294 2,133 183.72 74 335.29 0.0002
2020-05-13 2020-03-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,161 -237 -16.95 17 -37.04 0.0001
2020-02-04 2019-12-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 1,398 1,398 27 0.0001
2019-08-13 2019-06-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 0 -140 -100.00 0 -100.00
2019-05-08 2019-03-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 140 140 3 0.0000
2015-11-16 2015-09-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 0 -9,055 -100.00 0 -100.00
2015-08-10 2015-06-30 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 9,055 -340 -3.62 159 12.77 0.0006
2015-05-08 2015-03-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 9,395 -665 -6.61 141 20.51 0.0005
2015-02-13 2014-12-31 13F AMPHASTAR PHARMACEUTICALS IN COMMON STOCK 03209R103 10,060 10,060 117 0.0005
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.