Dun Haiping (CIK 1721581) reported 18 SEC Form 4 insider transactions across 1 companies over the past 18 months (most recent 2026-08-20). Recent activity: Buy ACMR (5,000 shares), Sell ACMR (1,200 shares), Sell ACMR (3,400 shares), Sell ACMR (400 shares), Buy ACMR (5,000 shares). Source: SEC Form 4.
| Date | Company | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-08-20 | ACM Research, Inc. (ACMR) | Director | Buy | 5,000 | $28,000 |
| 2026-08-20 | ACM Research, Inc. (ACMR) | Director | Sell | 1,200 | $96,348 |
| 2026-08-20 | ACM Research, Inc. (ACMR) | Director | Sell | 3,400 | $276,454 |
| 2026-08-20 | ACM Research, Inc. (ACMR) | Director | Sell | 400 | $32,868 |
| 2026-05-21 | ACM Research, Inc. (ACMR) | Director | Buy | 5,000 | $28,000 |
| 2026-05-21 | ACM Research, Inc. (ACMR) | Director | Sell | 1,333 | $85,099 |
| 2026-05-21 | ACM Research, Inc. (ACMR) | Director | Sell | 500 | $32,545 |
| 2026-05-21 | ACM Research, Inc. (ACMR) | Director | Sell | 1,309 | $87,978 |
| 2026-05-21 | ACM Research, Inc. (ACMR) | Director | Sell | 1,858 | $125,489 |
| 2026-03-11 | ACM Research, Inc. (ACMR) | Director | Buy | 5,000 | $28,000 |
| 2026-03-11 | ACM Research, Inc. (ACMR) | Director | Sell | 4,100 | $177,817 |
| 2026-03-11 | ACM Research, Inc. (ACMR) | Director | Sell | 900 | $39,546 |
| 2025-11-14 | ACM Research, Inc. (ACMR) | Director | Sell | 755,090 | $0 |
| 2025-03-18 | ACM Research, Inc. (ACMR) | Director | Sell | 2,456 | $69,554 |
| 2025-03-18 | ACM Research, Inc. (ACMR) | Director | Sell | 7,062 | $206,422 |
| 2025-03-12 | ACM Research, Inc. (ACMR) | Director | Sell | 15,001 | $398,127 |
| 2025-03-05 | ACM Research, Inc. (ACMR) | Director | Buy | 25,001 | $12,500 |
| 2025-03-05 | ACM Research, Inc. (ACMR) | Director | Sell | 482 | $12,503 |
Source: SEC Form 4 filings · as of 2026-08-20