Floyd F. Petersen - 11 Dec 2025 Form 4 Insider Report for Amphastar Pharmaceuticals, Inc. (AMPH)

Role: Director
Signature: /s/ Eva Wen, by power of attorney
Issuer symbol: AMPH
Transactions as of: 11 Dec 2025
Net transactions value: -$107,508
Form type: 4
Filing time: 15 Dec 2025, 17:17:42 UTC
Previous filing: 17 Nov 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Petersen Floyd F.	Director	C/O AMPHASTAR PHARMACEUTICALS, INC., 11570 6TH STREET, RANCHO CUCAMONGA	/s/ Eva Wen, by power of attorney	15 Dec 2025	0001611286

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	AMPH	Common Stock	Sale	$44,620	-1,737	-2.3%	$25.69	73,794	11 Dec 2025	Direct
transaction	AMPH	Common Stock	Sale	$62,888	-2,426	-3.3%	$25.92	71,368	12 Dec 2025	Direct	F1

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.9225 to $25.945, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

Content

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.9225 to $25.945, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.