Richard K. Prins - 19 Aug 2024 Form 4 Insider Report for Amphastar Pharmaceuticals, Inc. (AMPH)

Reporting relationship: Director
Issuer ticker: AMPH
Reported as of: 19 Aug 2024
Net transaction value: $0
SEC form: 4
Accepted by SEC: 03 Jun 2026, 21:22:11 UTC
Prior SEC filing: 12 Aug 2024
Next SEC filing: 13 Nov 2024
Source filing: View source filing
Reporting owner signature: /s/ Eva Wen, by power of attorney

Key filing fact

Richard K. Prins filed Form 4 for Amphastar Pharmaceuticals, Inc. (AMPH) on 03 Jun 2026.

Key facts

This page summarizes Richard K. Prins's Form 4 filing for Amphastar Pharmaceuticals, Inc. (AMPH).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 03 Jun 2026, 21:22.

Change

Previous filing in this sequence was filed on 12 Aug 2024.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001047579 Primary reporting owner

PRINS RICHARD K

Relationship: Director
Address: C/O AMPHASTAR PHARMACEUTICALS, INC., 11570 6TH STREET, RANCHO CUCAMONGA
Signature: /s/ Eva Wen, by power of attorney
Signature date: 03 Jun 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

AMPH transaction

Common Stock

Gift

Transaction value
Shares: -1,500
Change %: -4.8%
Price: $0.000000^*
Shares after: 29,455
Date: 19 Aug 2024
Ownership: Direct
Footnotes: F1

AMPH transaction

Common Stock

Award

Transaction value
Shares: +8,143
Change %: +28%
Price: $0.000000^*
Shares after: 37,598
Date: 01 Jun 2026
Ownership: Direct
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

AMPH transaction Derivative

Stock Option (right to buy)

Award

Transaction value
Shares: +17,365
Change %
Price: $0.000000^*
Shares after: 17,365
Date: 01 Jun 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 17,365
Exercise price: $18.42
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

The number of shares beneficially owned following the reported transaction is as of June 1, 2026 and has been reduced by 4,228 shares to reflect a reconciliation to the reporting person's account records.

Footnote F2

The reported shares are represented by restricted stock units, or RSUs, all of which vest on June 1, 2027.

Footnote F3

All of the shares subject to the option vest on June 1, 2027.