Amphastar Pharmaceuticals, Inc. — Director's Dealing 2020

May 28, 2020

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Amphastar Pharmaceuticals, Inc. (AMPH)
CIK: 0001297184
Period of Report: 2020-05-27

Reporting Person: Koo Richard (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2020-05-27	Common Stock	M	47782	$15.11	Acquired	295201	Direct
2020-05-27	Common Stock	S	47782	$18.1845	Disposed	247419	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2020-05-27	Stock Option (right to buy)	$15.11	M	47782	Disposed	2020-05-27	Common Stock (47782)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	10000	Indirect

Footnotes

F1: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $18.02 to $18.45, 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.

F2: The reported shares are held directly by Richard Y. Koo, a sole proprietorship, for which the Reporting Person is the sole owner.

F3: Shares subject to the option are fully vested and immediately exercisable.