STOCK TITAN

Ambiq Micro (AMBQ) President and COO receives 64,246-share RSU grant

Filing Impact
(Neutral)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

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

Ambiq Micro, Inc. President and COO Sean Chihhsiang Chen received an equity grant of 64,246 shares of common stock in the form of restricted stock units. The award was granted at no cash cost and increased his directly held common stock position to 120,275 shares.

Each RSU represents one share of common stock upon settlement. According to the vesting schedule, 25% of the RSUs will vest on September 1, 2027, with the remaining units vesting in equal quarterly installments over the following three years, subject to his continuous service under the company’s 2025 Equity Incentive Plan.

Positive

  • None.

Negative

  • None.
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)
  1. [object Object]
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 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)
Director 10% Owner
X Officer (give title below) Other (specify below)
President and COO
3. Date of Earliest Transaction (Month/Day/Year)
03/06/2026
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 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)
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 September 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).
/s/ Jeffrey Winzeler, Attorney-in-Fact 03/10/2026
** 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.

FAQ

What did Ambiq Micro (AMBQ) disclose about Sean Chen’s latest equity grant?

Ambiq Micro reported that President and COO Sean Chihhsiang Chen received a grant of 64,246 restricted stock units. Each RSU represents one share of common stock, awarded at no cash cost as part of his compensation package under the 2025 Equity Incentive Plan.

How many Ambiq Micro (AMBQ) shares does Sean Chen hold after this Form 4 transaction?

Following the RSU grant, Sean Chihhsiang Chen is shown holding 120,275 shares of Ambiq Micro common stock directly. This figure includes the newly granted 64,246 restricted stock units that will settle into shares as they vest over time.

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

The 64,246 restricted stock units vest over several years. Twenty-five percent of the RSUs vest on September 1, 2027, and the remaining units vest in equal quarterly installments thereafter, contingent on Sean Chen maintaining continuous service with Ambiq Micro.

Is Sean Chen’s Ambiq Micro RSU grant an open-market purchase or a compensation award?

The Form 4 classifies Sean Chen’s transaction as a grant or award acquisition, not an open-market purchase. The RSUs were granted at a price of $0.0000 per share as part of his equity compensation, subject to the company’s standard vesting conditions.

What does each restricted stock unit (RSU) represent in Ambiq Micro’s Form 4 filing?

Each restricted stock unit granted to Sean Chen represents a contingent right to receive one share of Ambiq Micro common stock. The shares are delivered only as the RSUs vest under the specified schedule and continuous service requirements set out in the 2025 Equity Incentive Plan.

What conditions must be met for Sean Chen’s Ambiq Micro RSUs to vest?

Vesting of Sean Chen’s RSUs depends on his continuous service with Ambiq Micro. The footnote specifies that vesting is subject to the definition of Continuous Service in the company’s 2025 Equity Incentive Plan governing the award’s terms and schedule.