[Form 4] Ambiq Micro, Inc. Insider Trading Activity

Ambiq Micro director and CEO Fumihide Esaka received a grant of 159,907 restricted stock units (RSUs) on 10/02/2025.

Rhea-AI Filing Summary

Ambiq Micro director and CEO Fumihide Esaka received a grant of 159,907 restricted stock units (RSUs) on 10/02/2025. Each RSU converts to one share of common stock upon settlement, and following the grant the Reporting Person beneficially owned 176,913 shares. Under the disclosed vesting schedule, 25% of the RSUs vest on 10/01/2026, with the remainder vesting in equal 1/12 portions quarterly thereafter, contingent on continuous service under the company’s 2025 Equity Incentive Plan. The Form 4 was signed by an attorney-in-fact on 10/06/2025.

Insights

Corporate Governance Expert

CEO received a time‑based RSU award that increases founder/officer equity stake and aligns compensation with tenure.

The grant of 159,907 RSUs is a common executive compensation mechanism that vests over time to encourage retention; 25% vests after one year with quarterly vesting thereafter. This structure ties value realization to continued service rather than immediate liquidity.

Key dependencies include the executive's continued service through the 10/01/2026 cliff and subsequent quarterly periods, and any corporate actions that affect share settlement. Investors should note the grant size relative to total outstanding shares when assessing dilution over the vesting horizon.

Insider Trade Summary

Grant/Award: 159,907 shares

Grant/Award 1 txn

Insider Esaka Fumihide

Role Chief Executive Officer

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	159,907	$0.00	$0.00

Holdings After Transaction: Common Stock — 176,913 shares (Direct)

Footnotes (1)

1. F1. Represents the grant of restricted stock units (RSUs). Each RSU represents a contingent right to receive one share of the Issuer's Common Stock upon settlement. 25% of the shares subject to the RSU will vest on October 1, 2026, and 1/12 of the shares subject to the RSU will vest quarterly thereafter, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2025 Equity Incentive Plan).

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Accepted by SEC EDGAR 10/06/2025 - 05:55 PM Learn about SEC filing dates

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)

(Street)

AUSTIN TX 78730

(City) (State) (Zip)

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

3. Date of Earliest Transaction (Month/Day/Year)
10/02/2025

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

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

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

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	10/02/2025		A		159,907(1)	A	$0	176,913	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

Explanation of Responses:

1. Represents the grant of restricted stock units (RSUs). Each RSU represents a contingent right to receive one share of the Issuer's Common Stock upon settlement. 25% of the shares subject to the RSU will vest on October 1, 2026, and 1/12 of the shares subject to the RSU will vest quarterly thereafter, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2025 Equity Incentive Plan).

	/s/ Jeffrey Winzeler, Attorney-in-Fact	10/06/2025
	** 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.