Amphastar Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US03209R1032

SecurityAMPH / Amphastar Pharmaceuticals, Inc.
InstitutionSignaturefd, Llc
Latest Disclosed Ownership588 shares
Latest Disclosed Value $ 11,519
Signaturefd, Llc reports 8.49% increase in ownership of AMPH / Amphastar Pharmaceuticals, Inc.

On April 7, 2026 - Signaturefd, Llc filed a 13F-HR form disclosing ownership of 588 shares of Amphastar Pharmaceuticals, Inc. (US:AMPH) valued at $11,519 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 20, 2026 disclosing 542 shares of Amphastar Pharmaceuticals, Inc.. This represents a change in shares of 8.49% during the quarter. The current value of the position is $10,996 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)
2026-04-07 2026-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 588 46 8.49 12 -21.43 0.0002
2026-01-20 2025-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 542 20 3.83 15 7.69 0.0002
2025-10-21 2025-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 522 -750 -58.96 14 -55.17 0.0002
2025-07-16 2025-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 1,272 400 45.87 29 16.00 0.0005
2025-05-02 2025-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 872 520 147.73 25 92.31 0.0005
2025-02-10 2024-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 352 0 0.00 13 -23.53 0.0002
2024-10-21 2024-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 352 0 0.00 17 21.43 0.0003
2024-07-29 2024-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 352 -15 -4.09 14 -12.50 0.0003
2024-05-03 2024-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 367 -8 -2.13 16 -30.43 0.0003
2024-02-01 2023-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 375 -86 -18.66 23 9.52 0.0005
2023-11-03 2023-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 461 -2 -0.43 21 -19.23 0.0006
2023-08-01 2023-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 463 10 2.21 27 62.50 0.0007
2023-04-28 2023-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 453 -26 -5.43 17 23.08 0.0005
2023-01-30 2022-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 479 -233 -32.72 13 -35.00 0.0004
2022-11-08 2022-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 712 -50 -6.56 20 -25.93 0.0007
2022-08-10 2022-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 762 43 5.98 27 3.85 0.0009
2022-05-02 2022-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 719 262 57.33 26 136.36 0.0008
2022-01-25 2021-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 457 124 37.24 11 83.33 0.0003
2021-10-28 2021-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 333 99 42.31 6 20.00 0.0002
2021-07-26 2021-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 234 -203 -46.45 5 -37.50 0.0002
2021-04-30 2021-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 437 -17 -3.74 8 -11.11 0.0004
2021-02-11 2020-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 454 51 12.66 9 12.50 0.0004
2020-11-03 2020-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 403 208 106.67 8 100.00 0.0004
2020-07-30 2020-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 195 119 156.58 4 300.00 0.0002
2020-04-23 2020-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 76 76 1 0.0001
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.