Rong Zhou - 17 Dec 2025 Form 4 Insider Report for Amphastar Pharmaceuticals, Inc. (AMPH)

Role
SENIOR EVP, PRODUCTION CENTER
Signature
/s/ Eva Wen, by power of attorney
Issuer symbol
AMPH
Transactions as of
17 Dec 2025
Net transactions value
-$145,493
Form type
4
Filing time
18 Dec 2025, 17:23:24 UTC
Previous filing
18 Mar 2025
Next filing
06 Mar 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Zhou Rong SENIOR EVP, PRODUCTION CENTER C/O AMPHASTAR PHARMACEUTICALS, INC., 11570 6TH STREET, RANCHO CUCAMONGA /s/ Eva Wen, by power of attorney 18 Dec 2025 0001645326

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction AMPH Common Stock Options Exercise $110,887 +9,787 +7.1% $11.33 147,830 17 Dec 2025 Direct F1
transaction AMPH Common Stock Sale $256,379 -9,787 -6.6% $26.20 138,043 17 Dec 2025 Direct F2
holding AMPH Common Stock 99,668 17 Dec 2025 See footnote F3
holding AMPH Common Stock 5,000 17 Dec 2025 See footnote F4

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction AMPH Employee Stock Option (right to buy) Options Exercise $0 -9,787 -100% $0.000000 0 17 Dec 2025 Common Stock 9,787 $11.33 Direct F5
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Includes 545 shares acquired on May 31, 2025 and one share acquired on November 30, 2025 under the Issuer's 2014 Employee Stock Purchase Plan.
F2 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.97 to $26.50, 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.
F3 The shares are held of record by the Zhou Family Trust for which the reporting person serves as a trustee.
F4 The shares are held of record by the reporting person's spouse.
F5 Shares subject to the option are fully vested and immediately exercisable.