Amphastar Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US03209R1032

SecurityAMPH / Amphastar Pharmaceuticals, Inc.
InstitutionLsv Asset Management
Latest Disclosed Ownership651,714 shares
Latest Disclosed Value $ 12,767
Lsv Asset Management reports 490.86% increase in ownership of AMPH / Amphastar Pharmaceuticals, Inc.

On May 11, 2026 - Lsv Asset Management filed a 13F-HR form disclosing ownership of 651,714 shares of Amphastar Pharmaceuticals, Inc. (US:AMPH) valued at $12,767,077 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 110,300 shares of Amphastar Pharmaceuticals, Inc.. This represents a change in shares of 490.86% during the quarter. The current value of the position is $12,187,052 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)
2026-05-11 2026-03-31 13F Amphastar Pharmaceuticals COM 03209R103 651,714 541,414 490.86 13 500.00 0.0275
2026-02-06 2025-12-31 13F Amphastar Pharmaceuticals COM 03209R103 110,300 37,000 50.48 3 100.00 0.0064
2025-11-06 2025-09-30 13F Amphastar Pharmaceuticals COM 03209R103 73,300 30,100 69.68 2 0.0043
2025-08-11 2025-06-30 13F Amphastar Pharmaceuticals COM 03209R103 43,200 0 0.00 1 -100.00 0.0023
2025-05-09 2025-03-31 13F Amphastar Pharmaceuticals COM 03209R103 43,200 6,800 18.68 1 0.00 0.0030
2025-02-13 2024-12-31 13F Amphastar Pharmaceuticals COM 03209R103 36,400 -44,000 -54.73 1 -66.67 0.0031
2024-11-12 2024-09-30 13F Amphastar Pharmaceuticals COM 03209R103 80,400 0 0.00 4 0.00 0.0084
2024-08-06 2024-06-30 13F Amphastar Pharmaceuticals COM 03209R103 80,400 -144,368 -64.23 3 -66.67 0.0070
2024-05-06 2024-03-31 13F Amphastar Pharmaceuticals COM 03209R103 224,768 -92,832 -29.23 10 -52.63 0.0204
2024-02-06 2023-12-31 13F Amphastar Pharmaceuticals COM 03209R103 317,600 105,232 49.55 20 111.11 0.0429
2023-11-03 2023-09-30 13F Amphastar Pharmaceuticals COM 03209R103 212,368 0 0.00 10 -25.00 0.0227
2023-08-02 2023-06-30 13F Amphastar Pharmaceuticals COM 03209R103 212,368 179,168 539.66 12 1,100.00 0.0269
2023-05-02 2023-03-31 13F Amphastar Pharmaceuticals COM 03209R103 33,200 22,500 210.28 1 0.0028
2023-02-08 2022-12-31 13F Amphastar Pharmaceuticals COM 03209R103 10,700 0 0.00 0 -100.00 0.0007
2022-11-07 2022-09-30 13F/A-1 Amphastar Pharmaceuticals COM 03209R103 10,700 -116,353 -91.58 301 -93.19 0.0007
2022-11-04 2022-09-30 13F Amphastar Pharmaceuticals COM 03209R103 127,053 0 4,420 0.0096
2022-08-10 2022-06-30 13F Amphastar Pharmaceuticals COM 03209R103 127,053 -12,700 -9.09 4,420 -11.90 0.0096
2022-05-12 2022-03-31 13F Amphastar Pharmaceuticals COM 03209R103 139,753 54,907 64.71 5,017 153.90 0.0092
2022-01-28 2021-12-31 13F Amphastar Pharmaceuticals COM 03209R103 84,846 35,546 72.10 1,976 110.89 0.0035
2021-11-04 2021-09-30 13F Amphastar Pharmaceuticals COM 03209R103 49,300 18,900 62.17 937 53.10 0.0017
2021-08-04 2021-06-30 13F Amphastar Pharmaceuticals COM 03209R103 30,400 30,400 612 0.0010
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.