DUN HAIPING

PrivateCIK: 1721581
Location

FREMONT, CA

DUN HAIPING sold 5K shares of ACM RESEARCH, INC. on the open market

Open‑market sale worth $331.1K. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 4 sales
InsiderDUN HAIPINGCIK 1721581
IssuerACM RESEARCH, INC.CIK 1680062
Director
Since Apr 2019
-5K
Net shares
Net seller
$331.1K
Total sold
4
Open market trades
0B · 4S
6
Total transactions
5K acquired · 10K disposed
Non-Derivative Transactions5

Class A Common Stock

Direct
M · Option Exercise

Shares

+5K

Price / share

$5.60

Trade value

$28K

% of position

New position
5/19/2026
0.005K

Class A Common Stock

Direct
S · Sale

Shares

1.33K

Price / share

$63.84

Trade value

$85.10K

% of position

26.7%
5/19/2026
5K3.67K

Class A Common Stock

Direct
S · Sale

Shares

500.00

Price / share

$65.09

Trade value

$32.55K

% of position

13.6%
5/19/2026
3.67K3.17K

Class A Common Stock

Direct
S · Sale

Shares

1.31K

Price / share

$67.21

Trade value

$87.98K

% of position

41.3%
5/19/2026
3.17K1.86K

Class A Common Stock

Direct
S · Sale

Shares

1.86K

Price / share

$67.54

Trade value

$125.49K

% of position

New position
5/19/2026
1.86K0.00
Total

Net shares

+0.00

Net value

-$303.11K

Derivative Transactions1

Stock Option

Direct
M · Option Exercise
Converts to

Class A Common Stock

5K shares

Shares

5K

Strike price

5.6

Held after

50K

Exercisable

5/19/2026
Non-Derivative Holdings (Post-Transaction)2

Class A Common Stock

Indirect
Shares owned755.09K

Class A Common Stock

Indirect
Shares owned100K
Total
855.09K indirect855.09K
Derivative Holdings (Post-Transaction)0
No derivative holdings reported
DUN HAIPING — Insider Transaction (Form 4) Filed May 21, 2026 | Finecho