Esaka Fumihide 4

4 · Ambiq Micro, Inc. · Filed May 18, 2026

AI-generated summary of this filing

Updated May 18, 2026

Ambiq Micro (AMBQ) CEO Esaka Exercises Options, Sells 60K Shares

What Happened

Fumihide Esaka, CEO of Ambiq Micro, exercised stock options and sold shares. On May 14 and 15, 2026 he exercised options to acquire a total of 120,000 shares (60,000 on 5/14 at $8.12; 45,463 on 5/15 at $8.12; 14,537 on 5/15 at $12.60) for aggregate exercise cost of about $1,039,526. Separately, on May 14 he sold 60,000 shares in an open-market transaction at a weighted average price of $70.02 for gross proceeds of $4,201,122. Several related derivative dispositions were reported at $0, reflecting conversion/exercise of derivative instruments (reported under code M).

Key Details

Transaction dates/prices:
- 2026-05-14: Exercised 60,000 shares @ $8.12 — cost $487,200.
- 2026-05-14: Sold 60,000 shares (open market) @ weighted avg $70.02 — proceeds $4,201,122 (sales ranged $70.00–$70.45; weighted average noted in filing).
- 2026-05-15: Exercised 45,463 shares @ $8.12 — cost $369,160.
- 2026-05-15: Exercised 14,537 shares @ $12.60 — cost $183,166.
- Several derivative dispositions reported at $0 (conversion/exercise of derivatives) on 5/14–5/15.
Shares owned after the transactions: not stated in the provided filing excerpt.
Notable footnotes:
- F1: The $70.02 sale price is a weighted average; individual sale prices ranged $70.00–$70.45.
- F2–F4: Vesting schedules for the underlying options are described (initial 1/4 vesting dates and monthly vesting thereafter).
Filing: Form 4 was filed May 18, 2026 reporting transactions on May 14–15, 2026. No late-filing indicator was provided in the supplied data.

Context

These entries are coded as exercise/conversion of derivatives (M) plus an open-market sale (S). Because Esaka exercised options and shares were sold the same days (at least for the May 14 activity), this appears to be an exercise with immediate sale of shares rather than a pure open-market buy—common for option-holders converting vested options into cash. The $0 derivative disposals reflect the conversion/cancellation of option instruments as part of these transactions. This report is factual and does not indicate the insider’s motivation.

Form 4

Period: 2026-05-14

DirectorChief Executive Officer

Transactions

Exercise/Conversion
Common Stock
2026-05-14$8.12/sh+60,000$487,200→ 451,189 total
Sale
Common Stock
[F1]
2026-05-14$70.02/sh−60,000$4,201,122→ 391,189 total
Exercise/Conversion
Common Stock
2026-05-15$8.12/sh+45,463$369,160→ 436,652 total
Exercise/Conversion
Common Stock
2026-05-15$12.60/sh+14,537$183,166→ 451,189 total
Exercise/Conversion
Stock Option (Right to Buy)
[F2]
2026-05-14−60,000→ 144,470 total
Exercise: $8.12Exp: 2029-02-20→ Common Stock (60,000 underlying)
Exercise/Conversion
Stock Option (Right to Buy)
[F2]
2026-05-15−45,463→ 99,007 total
Exercise: $8.12Exp: 2029-02-20→ Common Stock (45,463 underlying)
Exercise/Conversion
Stock Option (Right to Buy)
[F3]
2026-05-15−7,936→ 114,007 total
Exercise: $12.60Exp: 2031-05-25→ Common Stock (7,936 underlying)
Exercise/Conversion
Stock Option (Right to Buy)
[F4]
2026-05-15−6,601→ 184,543 total
Exercise: $12.60Exp: 2034-07-20→ Common Stock (6,601 underlying)

Footnotes (4)

[F1]The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $70.00 to $70.45 per share. 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 range set forth in this footnote.
[F2]1/4 of the shares subject to the option vested on February 21, 2020, and 1/48 of the shares subject to the option vested in equal monthly installments thereafter, subject to the Reporting Person's continued service.
[F3]1/48 of the shares subject to the option vested on June 26, 2021, and 1/48 of the shares subject to the option vested in equal monthly installments thereafter, subject to the Reporting Person's continued service.
[F4]1/4 of the shares subject to the option vested on January 1, 2024, and 1/48 of the shares subject to the option vest in equal monthly installments thereafter, subject to the Reporting Person's continued service.

Signature

/s/ Jeffrey Winzeler, Attorney-in-Fact|2026-05-18

1 file