Jack Y. Zhang - 09 Mar 2026 Form 4 Insider Report for Amphastar Pharmaceuticals, Inc. (AMPH)

Role
CEO & CHIEF SCIENTIFIC OFFICER, Director, 10%+ Owner
Signature
/s/ Eva Wen, by power of attorney for Jack Y. Zhang
Issuer symbol
AMPH
Transactions as of
09 Mar 2026
Net transactions value
$0
Form type
4
Filing time
11 Mar 2026, 17:58:21 UTC
Previous filing
10 Mar 2026
SEC
View on sec.gov

Reporting Owners (2)

Name Relationship Address Signature Signature date CIK
Zhang Jack Y. CEO & CHIEF SCIENTIFIC OFFICER, Director, 10%+ Owner C/O AMPHASTAR PHARMACEUTICALS, INC., 11570 6TH STREET, RANCHO CUCAMONGA /s/ Eva Wen, by power of attorney for Jack Y. Zhang 11 Mar 2026 0001611157
Luo Mary Z. COO, Chief Scientist, Chairman, Director, 10%+ Owner C/O AMPHASTAR PHARMACEUTICALS, INC., 11570 6TH STREET, RANCHO CUCAMONGA /s/ Eva Wen, by power of attorney for Mary Z. Luo 11 Mar 2026 0001611156

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction AMPH Common Stock Award +180,504 +6.4% $0.000000* 3,014,621 09 Mar 2026 Direct F1
transaction AMPH Common Stock Tax liability -14,785 -0.49% $18.91* 2,999,836 10 Mar 2026 Direct F2
transaction AMPH Common Stock Award +72,462 +6.1% $0.000000* 1,252,428 09 Mar 2026 See footnote F1, F3
transaction AMPH Common Stock Tax liability -4,395 -0.35% $18.91* 1,248,033 10 Mar 2026 See footnote F2, F3
holding AMPH Common Stock 6,827,679 09 Mar 2026 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) Award +372,338 $0.000000* 372,338 09 Mar 2026 Common Stock 372,338 $19.21 Direct F5
transaction AMPH Employee Stock Option (right to buy) Award +149,472 $0.000000* 149,472 09 Mar 2026 Common Stock 149,472 $19.21 See footnote F3, F5
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 The reported shares are represented by restricted stock units, or RSUs, which vest in four equal annual installments beginning on March 9, 2027.
F2 The reported shares were withheld to satisfy the reporting person's tax liability in connection with the vesting of RSUs.
F3 The securities are held of record by Mary Z. Luo. The reporting persons are husband and wife.
F4 The shares are held of record by Applied Physics and Chemistry Laboratories, Inc., of which the reporting persons and The Bill Luobei Zhang 2004 Irrevocable Trust are the sole owners.
F5 The shares subject to the option vest in four equal annual installments beginning on March 9, 2027.