Chen Sean Chihhsiang 4

What Happened
Sean Chihhsiang Chen, President and COO of Ambiq Micro (AMBQ), exercised 55,685 stock options at $5.88 per share (total cost ~$327,428) on May 15, 2026, and sold the resulting 55,685 shares in the open market the same day for combined gross proceeds of approximately $3,947,281. The sales were executed in two tranches (32,351 shares and 23,334 shares) at weighted average prices of $70.53 and $71.37, respectively. This sequence — exercising options and immediately selling the shares — is effectively a cashless exercise followed by open-market sales.

Key Details

• Transaction date: May 15, 2026 (Form 4 filed May 18, 2026 — within the 2-business-day SEC filing window).
• Option exercise: 55,685 shares acquired at $5.88 each; total exercise cost ≈ $327,428.
• Open-market sales: 32,351 shares at a weighted avg $70.53 (≈ $2,281,826) and 23,334 shares at a weighted avg $71.37 (≈ $1,665,455); total proceeds ≈ $3,947,281. Combined avg sale price ≈ $70.89/share.
• Footnote sale price ranges: first tranche prices ranged $70.02–$71.0097; second tranche ranged $71.025–$71.85. (Reporting person can provide per-trade breakdown on request.)
• Derivative reporting: the filing also shows the option converted/terminated (derivative disposition reported at $0.00) consistent with exercise.
• Vesting note: the option originally vested 1/4 on Nov 3, 2017 with 1/48 vesting monthly thereafter (per footnote).
• Shares owned after transaction: not provided in the excerpt supplied.

Context

• This is a common pattern where an insider exercises vested options and immediately sells the shares to capture value or cover exercise/payment — often described as a cashless exercise. It reports both the exercise (an acquisition of shares via derivative conversion) and subsequent open-market sales.
• The filing is factual disclosure of transactions; it does not state the insider’s motivation. Purchases generally carry more directional signal than routine sales tied to option exercises, and in this case the exercise + immediate sale appears to be a liquidity event rather than a new long-term buy.