Ambiq Micro (AMBQ) CEO exercises options and sells 60,000 shares

Rhea-AI Filing Summary

Ambiq Micro Chief Executive Officer Esaka Fumihide reported option exercises and a stock sale. On May 14, 2026, he exercised options to acquire 60,000 shares of common stock at $8.12 per share and sold 60,000 shares in an open‑market transaction at a weighted average price of $70.0187 per share.

On May 15, 2026, he reported additional option exercises that increased his direct holdings without same‑day sales, including exercises at $12.60 per share. Following these transactions, he directly held 451,189 shares of Ambiq Micro common stock, while continuing to hold multiple stock option positions with stated vesting schedules and expirations.

Insights

Equity compensation and governance analyst

CEO executed routine option exercises with a partial same‑day sale.

The filing shows Esaka Fumihide exercising stock options and selling some shares. On May 14, 2026, he exercised options at $8.12 per share and sold 60,000 shares at a weighted average of $70.0187. This is a classic exercise‑and‑sell pattern converting part of an option position into cash.

Across May 14–15, 2026, the data show 120,000 shares acquired via option exercises and a net sale of 60,000 shares, leaving him with 451,189 common shares held directly. Because the sale is a fraction of his post‑transaction holdings, it appears as a partial liquidity event rather than a full exit.

The derivative records indicate remaining options, including grants with exercise prices such as $12.60 per share and expirations extending to July 20, 2034. Overall, this mix of exercises, a single disclosed open‑market sale, and substantial remaining equity exposure suggests routine executive equity management rather than a decisive change in ownership stance.

Insider Trade Summary

Net Seller: 60,000 shares ($4,201,122)

Net Sell 8 txns

Insider Esaka Fumihide

Role Chief Executive Officer

Sold 60,000 shs ($4.20M)

Type	Security	Shares	Price	Value
Exercise	Stock Option (Right to Buy)	45,463	$0.00	--
Exercise	Stock Option (Right to Buy)	7,936	$0.00	--
Exercise	Stock Option (Right to Buy)	6,601	$0.00	--
Exercise	Common Stock	45,463	$8.12	$369K
Exercise	Common Stock	14,537	$12.60	$183K
Exercise	Stock Option (Right to Buy)	60,000	$0.00	--
Exercise	Common Stock	60,000	$8.12	$487K
Sale	Common Stock	60,000	$70.0187	$4.20M

Holdings After Transaction: Stock Option (Right to Buy) — 99,007 shares (Direct, null); Common Stock — 436,652 shares (Direct, null)

Footnotes (1)

1. 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. 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. 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. 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.

Key Figures

Shares sold: 60,000 shares Weighted average sale price: $70.0187 per share Shares acquired via exercises: 120,000 shares +4 more

7 metrics

Shares sold 60,000 shares Open-market sale of common stock on May 14, 2026

Weighted average sale price $70.0187 per share Common stock sale on May 14, 2026

Shares acquired via exercises 120,000 shares Option exercises summarized in transactionSummary

Holdings after transactions 451,189 shares Direct common stock held following reported trades

Option exercise price $8.12 per share Common stock acquired through option exercises

Option exercise price $12.60 per share Additional common stock acquired via options

Option expiration July 20, 2034 Stock option grant with $12.60 exercise price

Key Terms

Stock Option (Right to Buy), weighted average sale price, open-market sale, vested in equal monthly installments, +1 more

5 terms

Stock Option (Right to Buy) financial

"security_title: "Stock Option (Right to Buy)" with underlying common stock shares"

weighted average sale price financial

"The reported price in Column 4 is a weighted average sale price."

open-market sale financial

"transaction_action: "open-market sale" for 60,000 common shares"

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

vested in equal monthly installments financial

"1/48 of the shares subject to the option vested in equal monthly installments thereafter"

derivative security financial

"transaction_code_description: "Exercise or conversion of derivative security""

A derivative security is a financial contract whose value comes from the price or performance of something else, such as a stock, bond, commodity, or market index. For investors it acts like an insurance policy or a wager: it can be used to protect against losses, lock in prices, or amplify gains and losses, so it can change a portfolio’s risk and potential return without owning the underlying asset directly.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Esaka Fumihide

(Last) (First) (Middle)

C/O AMBIQ MICRO, INC.

6500 RIVER PLACE BLVD BUILDING 7 STE 200

(Street)

AUSTIN TEXAS 78730

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Ambiq Micro, Inc. [ AMBQ ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/14/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/14/2026		M		60,000	A	$8.12	451,189	D
Common Stock	05/14/2026		S		60,000	D	$70.0187(1)	391,189	D
Common Stock	05/15/2026		M		45,463	A	$8.12	436,652	D
Common Stock	05/15/2026		M		14,537	A	$12.6	451,189	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (Right to Buy)	$8.12	05/14/2026		M			60,000	(2)	02/20/2029	Common Stock	60,000	$0	144,470	D
Stock Option (Right to Buy)	$8.12	05/15/2026		M			45,463	(2)	02/20/2029	Common Stock	45,463	$0	99,007	D
Stock Option (Right to Buy)	$12.6	05/15/2026		M			7,936	(3)	05/25/2031	Common Stock	7,936	$0	114,007	D
Stock Option (Right to Buy)	$12.6	05/15/2026		M			6,601	(4)	07/20/2034	Common Stock	6,601	$0	184,543	D

Explanation of Responses:

1. 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.

2. 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.

3. 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.

4. 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.

	/s/ Jeffrey Winzeler, Attorney-in-Fact	05/18/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What did Ambiq Micro (AMBQ) CEO Esaka Fumihide report in this Form 4?

He reported exercising stock options and selling shares of Ambiq Micro common stock. The transactions include option exercises on May 14–15, 2026 and a same‑day open‑market sale, updating his direct share ownership and remaining equity exposure.

How many Ambiq Micro (AMBQ) shares did the CEO sell and at what price?

Esaka Fumihide sold 60,000 shares of Ambiq Micro common stock. The filing states a weighted average sale price of $70.0187 per share, with individual trades executed between $70.00 and $70.45, as detailed in the accompanying weighted‑average price footnote.

How many Ambiq Micro (AMBQ) shares did the CEO acquire through option exercises?

The transaction summary reports 120,000 shares acquired via option exercises. These exercises include common stock obtained at an exercise price of $8.12 per share and additional grants at $12.60 per share, converting derivative awards into directly held Ambiq Micro common stock.

What is the Ambiq Micro (AMBQ) CEO’s direct shareholding after these transactions?

Following the reported trades, Esaka Fumihide directly holds 451,189 shares of Ambiq Micro common stock. This figure reflects his position after exercising options and selling 60,000 shares, indicating he retains a substantial ongoing equity stake in the company.

Were the Ambiq Micro (AMBQ) CEO’s sales executed at a single price or multiple prices?

The filing specifies a weighted average sale price, meaning shares were sold at multiple prices. A footnote explains that the 60,000 shares were sold in separate transactions between $70.00 and $70.45 per share, with full trade breakdowns available upon request.

What do the vesting footnotes in the Ambiq Micro (AMBQ) Form 4 indicate about the CEO’s options?

The footnotes describe time‑based vesting schedules for several option grants. Portions vested on specific past dates, with the remaining shares vesting in equal monthly installments, contingent on the CEO’s continued service, and have stated expiration dates extending into future years.