Ambiq Micro (AMBQ) CEO Esaka Exercises Options, Sells 108,500 Shares

What Happened
Esaka Fumihide, CEO of Ambiq Micro, exercised options totaling 117,771 shares (cash paid ≈ $1.42M) across Aug 31–Sep 2, 2026, and sold 108,500 shares in multiple open‑market trades for aggregate proceeds of roughly $6.17M. Most sales occurred same day as exercises, meaning the transactions effectively converted option holdings to stock and disposed of the majority of those shares (routine liquidity rather than an outright new purchase).

Key Details

• Transaction dates: Aug 31, 2026; Sep 1, 2026; Sep 2, 2026.
• Option exercises (code M): 117,771 shares acquired for ≈ $1,423,435 (aggregate exercise cost).
• Open‑market sales (code S): 108,500 shares sold for ≈ $6,172,548 (aggregate proceeds).
• Net effect: exercised 117,771 vs sold 108,500 → net increase of 9,271 shares retained.
• Sales were executed in multiple trades at weighted average prices (individual sale prices ranged roughly from mid‑$55s to high‑$58s per share; see filing footnotes for exact ranges).
• Transactions were made under a Rule 10b5‑1 trading plan (footnote F1).
• Vesting/option notes included in filing (F11–F13) describe original option vesting schedules.
• Filing date: Sep 2, 2026 (covering activity through Sep 2) — no late‑filing flag indicated in the provided data.
• Shares owned after transaction: not stated in the supplied summary of the Form 4.

Context

• The M code entries mean Esaka exercised stock options; the subsequent S entries show the exercised shares were mostly sold, so these acted like cashless exercises/liquidity events.
• Footnotes note weighted‑average sale prices and provide price ranges for groups of sales; the reporting person offers to disclose per‑trade detail on request.
• These are insider transactions by the CEO and documented under a pre‑arranged (10b5‑1) plan — common for scheduled sales; factual disclosure does not indicate the insider’s motive.