Ambiq Micro (NASDAQ: AMBQ) President and COO receives 64,246 RSU equity award

Filing Impact

(Neutral)

Filing Sentiment

(Neutral)

Form Type

4/A

Rhea-AI Filing Summary

Chen Sean Chihhsiang reported acquisition or exercise transactions in this Form 4 filing.

Ambiq Micro, Inc. reported that President and COO Sean Chihhsiang Chen received an equity grant of 64,246 shares of common stock in the form of restricted stock units. These RSUs were granted at no cash purchase price and increase his direct holdings to 120,275 shares after the award.

Each RSU represents a contingent right to receive one share of Ambiq Micro common stock upon settlement. According to the vesting schedule, 25% of the RSUs will vest on October 1, 2027, and the remaining shares will vest in equal quarterly installments over the following three years, as long as Chen maintains continuous service under the company’s 2025 Equity Incentive Plan.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Chen Sean Chihhsiang

Role President and COO

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	64,246	$0.00	--

Holdings After Transaction: Common Stock — 120,275 shares (Direct)

Footnotes (1)

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Key Figures

RSUs granted: 64,246 shares Transaction price per share: $0.0000 per share Holdings after transaction: 120,275 shares +2 more

5 metrics

RSUs granted 64,246 shares Restricted stock unit award to President and COO on March 6, 2026

Transaction price per share $0.0000 per share RSU grant issued as compensation, not a cash purchase

Holdings after transaction 120,275 shares Sean Chen’s direct common stock holdings following the RSU award

Initial vesting tranche 25% of RSUs Vests on October 1, 2027, subject to continuous service

Subsequent vesting pattern 1/12 of RSUs quarterly Quarterly vesting after October 1, 2027, under 2025 Equity Incentive Plan

Key Terms

restricted stock units (RSUs), contingent right, Continuous Service, 2025 Equity Incentive Plan

4 terms

restricted stock units (RSUs) financial

"Represents the grant of restricted stock units (RSUs). Each RSU represents a contingent right"

Restricted stock units (RSUs) are a type of company promise to give employees shares of stock in the future, usually after certain conditions like working for a set time. They are like a gift promised today that you receive later, which can become valuable if the company's stock price goes up. RSUs matter because they are a way companies reward employees and can be a significant part of compensation.

contingent right financial

"Each RSU represents a contingent right to receive one share of the Issuer's Common Stock"

Continuous Service financial

"will vest quarterly thereafter, subject to the Reporting Person's Continuous Service"

2025 Equity Incentive Plan financial

"Continuous Service (as defined in the Issuer's 2025 Equity Incentive Plan)"

Form 4 Insider Transactions: What Each Field Means →

04/02/2026 - 04:35 PM

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^*

Chen Sean Chihhsiang

(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)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	President and COO

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/06/2026

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)
03/10/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	03/06/2026		A		64,246⁽¹⁾	A	$0	120,275	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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

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, 2027, 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).

Remarks:

This Form 4 is being amended solely to correct an inadvertent administrative error affecting the vesting commencement date of the RSUs reported herein.

	/s/ Jeffrey Winzeler, Attorney-in-Fact	04/02/2026
	** 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)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transaction did AMBQ report for President and COO Sean Chen?

Ambiq Micro reported that President and COO Sean Chen received 64,246 restricted stock units. These RSUs were granted at no cash price and increased his direct common stock holdings to 120,275 shares following the award.

How many Ambiq Micro (AMBQ) shares did Sean Chen hold after this RSU grant?

After the grant, Sean Chen directly held 120,275 shares of Ambiq Micro common stock. This total includes the newly awarded 64,246 restricted stock units that convert into shares as they vest over time.

What is the vesting schedule for Sean Chen’s 64,246 AMBQ RSUs?

The RSUs vest over several years. Twenty-five percent of the 64,246 RSUs vest on October 1, 2027, and the remaining three-quarters vest in equal quarterly installments thereafter, conditioned on his continued service with Ambiq Micro.

Did Sean Chen pay a purchase price for his Ambiq Micro RSU grant?

No purchase price was paid for the RSU grant. The filing lists the transaction price per share as 0.0000, reflecting a compensation-related equity award rather than an open-market share purchase by Sean Chen.

What does each RSU granted to Sean Chen by AMBQ represent?

Each RSU represents a contingent right to receive one share of Ambiq Micro common stock upon settlement. Actual delivery of shares depends on the RSUs vesting under the stated schedule and Chen maintaining continuous service with the company.

Under which plan were Sean Chen’s Ambiq Micro RSUs granted?

The RSUs were granted under Ambiq Micro’s 2025 Equity Incentive Plan. Vesting requires Sean Chen’s “Continuous Service” as defined in that plan, linking the award to his ongoing employment with the company.