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Amphastar Pharmaceuticals, Inc.

AMPH Net selling
CIK 0001297184 #2610 in the set updated 17 Sep 2026
Bought (120 mo)
$663.08K
out of their own pocket, the only kind of buying there is
Sold (120 mo)
$125.69M
$20.49M on a plan · $70.74M straight out of an exercise
Sold at will
$34.46M
151 of 395 sales
Net
−$125.02M
−$33.80M against sales at will

By person

18 insiders · 415 transactions
142×

Jack Yongfeng Zhang holds 142 times base salary in stock. $135.24M of shares against $950.91K in salary for 2025.

Salary from the company's own proxy. The shares are what Jack Yongfeng Zhang last reported holding, valued at $23.63, the price Common Stock was last bought or sold at on the open market here, on 2 Sep 2026.

Insider
Role
Bought
Sold
Net
Holding
Worth
Change
Zhang Jack Y.
CEO & CHIEF SCIENTIFIC OFFICER
$642.82K (2)
$31.38M (35)
−$30.73M
5,723,548
$135.24M
+8.9%
PETERS WILLIAM J
CFO, EVP & TREASURER
$23.02M (66) scheduled
−$23.02M
172,846
$4.08M
+130.2%
Luo Mary Z.
COO,Chief Scientist & Chairman
$19.97M (14) scheduled
−$19.97M
1,104,416
$26.10M
−24.1%
Shandell Jason B.
President and General Counsel
$8.21M (32) scheduled
−$8.21M
179,276
$4.24M
−19.4%
Liawatidewi Yakob
EVP CORP ADMIN CENTER
$7.14M (36) scheduled
−$7.14M
126,810
$3.00M
+114.9%
PRINS RICHARD K
Director
$6.41M (32) scheduled
−$6.41M
29,625
$700.01K
+36.1%
Zhou Rong
SENIOR EVP, PRODUCTION CENTER
$6.29M (33) scheduled
−$6.29M
354,197
$8.37M
+52.0%
ZASLOFF MICHAEL A
Director
$5.97M (14) scheduled
−$5.97M
37,667
$890.04K
+16.2%
Lee Howard
Director
$4.29M (17) scheduled
−$4.29M
159,350
$3.77M
+39.1%
Petersen Floyd F.
Director
$4.29M (79) scheduled
−$4.29M
71,368
$1.69M
+18.3%
Applied Physics & Chemistry Laboratories, Inc. entity
10% owner
$2.85M (4)
−$2.85M
7,327,679
$173.15M
−1.8%
Shohet Stephen B.
Director
$2.73M (13) scheduled
−$2.73M
30,706
$725.56K
+68.0%
Koo Richard
Director
$1.99M (3) scheduled
−$1.99M
269,289
$6.36M
+12.4%
Gerst Diane G.
Director
$652.31K (14) scheduled
−$652.31K
31,899
$753.74K
Deflin Gayle
Director
$494.45K (3)
−$494.45K
19,057
$450.30K
Maris David
Director
$20.26K (1)
+$20.26K
19,170
$452.97K
+204.3%
Gaugh David Russell
Director
14,447
$341.37K
Pierce Anthony T
Director
7,886
$186.34K

No percentages here. These insiders hold more than one class of share between them, and the share count on file covers one of them rather than all. Dividing the two would compare different things.

Insider
Date
Role
Action
Shares
Price
Amount
Zhang Jack Y.
13 Jun 2025
CEO & CHIEF SCIENTIFIC OFFICER
Exercised, kept
200,000
$13.03
$2.61M
Zhang Jack Y.
14 Mar 2025
CEO & CHIEF SCIENTIFIC OFFICER
Exercised, kept indirect
211,213
$14.69
$3.10M
Zhang Jack Y.
14 Mar 2025
CEO & CHIEF SCIENTIFIC OFFICER
Exercised, kept
290,477
$14.69
$4.27M
Zhang Jack Y.
13 Sep 2024
CEO & CHIEF SCIENTIFIC OFFICER
Exercised, kept
100,000
$14.69
$1.47M
Zhang Jack Y.
10 Jun 2024
CEO & CHIEF SCIENTIFIC OFFICER
Exercised, kept
100,000
$14.69
$1.47M
Zhang Jack Y.
15 Mar 2024
CEO & Chief Scientific Officer
Exercised, kept indirect
310,930
$12.46
$3.87M
Zhang Jack Y.
15 Mar 2024
CEO & Chief Scientific Officer
Exercised, kept
722,046
$12.46
$9.00M
Zhou Rong
20 Jun 2023
EVP, Production Center
Exercised, kept
9,651
$11.33
$109.35K
Showing 250 of 415 transactions. The figures above use every one of them.

What was left out

Form 4 filings counted 484
Amendments (4/A) skipped 1
Filings about a different issuer 0
Unreadable filings 0
Joint filings 50
Sales on a Rule 10b5-1 plan 39
Sales straight out of an exercise 205
Sales at will 151
Transactions with no price 0
Shares from compensation/vesting 15,900,120
Sales filed before the plan box existed 133
History held since 2 Sep 2016