SIMO · Insider Trading
Silicon Motion Technology Corporation
Every open-market purchase and sale reported by SIMO officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-06-24 | Kuan-Ming Lin | Director | Sell | −3,000 | −$930.32K |
| 2026-06-24 | Han-Ping Shieh | Director | Sell | −2,000 | −$629.25K |
| 2026-05-07 | Shii Tyng Duann | Director | Sell | −1,500 | −$367.50K |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Shii Tyng Duann | Director | 15,200 | $2.90M |
| Kuan-Ming Lin | Director | 8,500 | $1.62M |
| Han-Ping Shieh | Director | 6,655 | $1.27M |
Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.
Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.
Full filing history and per-insider positions are on the SIMO quote page; the site-wide leaderboard is on the insider transactions hub.
Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.