Amphastar Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US03209R1032

SecurityAMPH / Amphastar Pharmaceuticals, Inc.
InstitutionMan Group plc
Latest Disclosed Ownership37,274 shares
Latest Disclosed Value $ 730,198
Man Group plc reports 163.40% increase in ownership of AMPH / Amphastar Pharmaceuticals, Inc.

On May 15, 2026 - Man Group plc filed a 13F-HR form disclosing ownership of 37,274 shares of Amphastar Pharmaceuticals, Inc. (US:AMPH) valued at $730,198 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 14,151 shares of Amphastar Pharmaceuticals, Inc.. This represents a change in shares of 163.40% during the quarter. The current value of the position is $675,405 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)
2026-05-15 2026-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 37,274 23,123 163.40 730 93.12 0.0013
2026-02-17 2025-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 14,151 -18,234 -56.30 379 -56.20 0.0006
2025-11-14 2025-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 32,385 12,085 59.53 863 85.19 0.0015
2025-08-14 2025-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 20,300 -17,937 -46.91 466 -57.94 0.0009
2025-05-15 2025-03-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 38,237 16,412 75.20 1,108 36.79 0.0028
2025-02-14 2024-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 21,825 21,825 810 0.0021
2024-11-14 2024-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 0 -8,776 -100.00 0 -100.00
2024-08-14 2024-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 8,776 8,776 351 0.0009
2019-02-14 2018-12-31 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 0 -18,451 -100.00 0 -100.00
2018-11-14 2018-09-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 18,451 6,556 55.12 355 95.05 0.0013
2018-08-14 2018-06-30 13F AMPHASTAR PHARMACEUTICALS IN COM 03209R103 11,895 11,895 182 0.0007
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.