ACM Research director sells 5K shares in $80–82 range
Sentiment and the balance of points
Rhea-AI Sentiment reads the wording of the document, how positive or negative its language is on a 1 to 5 scale. The balance of points shown with the takes weighs what the document actually discloses, so the two can disagree, for example when a trial that missed its main goal is described in upbeat language.
Form Type
4
Rhea-AI Filing Summary
ACM Research, Inc. (ACMR) director Haiping Dun exercised stock options for 5,000 shares of Class A Common Stock at an exercise price of $5.60 per share, from a fully vested option, and on the same date sold 5,000 shares in multiple open-market transactions at weighted average prices between $79.89 and $82.33 pursuant to a Rule 10b5-1 trading plan adopted on August 13, 2025. Following the option exercise, Dun held 45,000 stock options directly and reported indirect holdings of 100,000 shares in the Dun Family GST Trust and 755,090 shares in the Haiping Dun & Chi-Pin H Dun Revocable Trust.
Insider Trade Summary 10b5-1
Exercise and Sale: 5,000 shares ($378K approx. pre-tax spread)
Exercise and Sale
7 txns
Insider
Dun Haiping
Role
Director
Sold
5,000 shs ($406K)
Approx. gross sale proceeds
$406K
Approx. exercise cost
$28K
Approx. pre-tax spread
$378K
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Exercise | Stock Option F5 | 5,000 | $0.00 | $0.00 |
| Exercise | Class A Common Stock | 5,000 | $5.60 | $28K |
| Sale | Class A Common Stock F1, F2 | 1,200 | $80.29 | $96K |
| Sale | Class A Common Stock F1, F3 | 3,400 | $81.31 | $276K |
| Sale | Class A Common Stock F1, F4 | 400 | $82.17 | $33K |
| holding | Class A Common Stock | -- | -- | -- |
| holding | Class A Common Stock | -- | -- | -- |
Holdings After Transaction:
Stock Option — 45,000 contracts (Direct);
Class A Common Stock — 0 shares (Direct);
Class A Common Stock — 100,000 shares (Indirect, Dun Family GST Trust);
Class A Common Stock — 755,090 shares (Indirect, Haiping Dun & Chi-Pin H Dun Revocable Trust)
Footnotes (5)
- F1. The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 13, 2025.
- F2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $79.89 to $80.77, 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 within the ranges set forth in footnote (2), (3), and (4) to this Form 4.
- F3. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $80.95 to $81.91, inclusive.
- F4. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $81.97 to $82.33, inclusive.
- F5. The option is fully vested and exercisable.
Key Figures
Options exercised: 5,000 shares
Option exercise price: $5.60 per share
Shares sold at $80.29: 1,200 shares at $80.29 per share
+5 more
8 metrics
Options exercised
5,000 shares
Stock option exercise into Class A Common Stock on 2026-08-18
Option exercise price
$5.60 per share
Exercise price of stock option expiring 2029-04-22
Shares sold at $80.29
1,200 shares at $80.29 per share
Weighted average price, trades ranged from $79.89 to $80.77
Shares sold at $81.31
3,400 shares at $81.31 per share
Weighted average price, trades ranged from $80.95 to $81.91
Shares sold at $82.17
400 shares at $82.17 per share
Weighted average price, trades ranged from $81.97 to $82.33
Options held after transaction
45,000 options
Total stock options following the reported exercise
Indirect GST Trust holdings
100,000 shares
Class A Common Stock held via Dun Family GST Trust
Indirect Revocable Trust holdings
755,090 shares
Class A Common Stock held via Haiping Dun & Chi-Pin H Dun Revocable Trust
Key Terms
Rule 10b5-1 trading plan, weighted average price, Class A Common Stock, stock option, +1 more
5 terms
Rule 10b5-1 trading plan regulatory
"The sales reported ... were effected pursuant to a Rule 10b5-1 trading plan"
A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.
weighted average price financial
"The price reported in Column 4 is a weighted average price."
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
Class A Common Stock financial
"underlying_security_title: "Class A Common Stock""
Class A common stock is a category of a company’s shares that carries a specific set of ownership rights—most commonly defined voting power and claims on dividends—set out in the company’s charter. For investors it matters because the class determines how much influence you have over corporate decisions, the share’s likely dividend and trading behavior, and how it compares in value to other share classes, like choosing a particular seat with different privileges at the company’s decision-making table.
stock option financial
"security_title: "Stock Option" with an exercise price of $5.6000"
A stock option is a contract that gives you the right to buy or sell a company's stock at a specific price within a certain time frame. People use them to potentially make money if the stock's price moves favorably or to protect against losses. It's like holding a coupon that can be used to buy or sell stock at a set price later on.
indirect ownership financial
"ownership_type: "indirect" through named trusts"
FAQ
AI-generated questions and answers. How Rhea-AI works. Not financial advice.
What insider transactions did ACMR director Haiping Dun report on this Form 4?
Haiping Dun reported exercising 5,000 stock options at $5.60 per share and selling a total of 5,000 Class A Common shares in multiple open-market transactions at weighted average prices between $79.89 and $82.33 on August 18, 2026.
Were Haiping Dun’s ACMR stock sales under a Rule 10b5-1 trading plan?
Yes. The filing states the sales were effected pursuant to a Rule 10b5-1 trading plan adopted by Haiping Dun on August 13, 2025, indicating the trades followed a pre-arranged plan rather than ad hoc timing decisions.
How many stock options does Haiping Dun hold after these ACMR transactions?
After exercising 5,000 options, Dun held 45,000 stock options on ACM Research, Inc. common stock, with the reported option having an exercise price of $5.60 per share and an expiration date of April 22, 2029.
AI-generated analysis. How Rhea-AI works. Not financial advice.
