[Form 4] Ambarella, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Ambarella, Inc. director Chenming Hu received an annual restricted stock unit (RSU) grant of 2,498 ordinary shares. The grant was approved by the board effective September 2, 2025, and vests in four equal quarterly installments beginning on the vesting start date of September 15, 2025, reaching 100% vesting on September 15, 2026, subject to continued service. After the grant, Mr. Hu beneficially owns 29,516 ordinary shares. The Form 4 was signed on behalf of Mr. Hu by an attorney-in-fact on September 4, 2025.

Positive

• Board-approved RSU grant of 2,498 shares which aligns the director's interests with shareholders through equity compensation
• Clear vesting schedule: quarterly vesting beginning 09/15/2025 and 100% vested by 09/15/2026, promoting retention

Negative

• None.

Insights

Financial Analyst

TL;DR: Routine annual director equity grant; modest dilution and aligns director incentives.

The Form 4 discloses a board-approved annual RSU award of 2,498 shares to an independent director, vesting quarterly over one year. This is a customary component of director compensation designed to align long-term interests with shareholders. The post-transaction beneficial ownership is 29,516 shares, which provides context on the director's existing stake. The disclosure is straightforward and administrative in nature, with limited immediate impact on financials or share count.

Corporate Governance Expert

TL;DR: Governance practice appears standard: annual RSU grant tied to continued service with one-year cliff-style schedule.

The filing indicates the company follows a predictable director compensation practice by issuing RSUs that vest over a defined service period. The quarterly vesting schedule beginning September 15, 2025, and full vesting by September 15, 2026, suggests a retention focus. The disclosure includes signature by an attorney-in-fact, which is acceptable but investors may note the indirect signature method for completeness of records. Overall, the item is procedural rather than material.

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
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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^*

Hu Chenming

(Last) (First) (Middle)

3001 TASMAN DRIVE

(Street)

SANTA CLARA CA 95054

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
AMBARELLA INC [ AMBA ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
09/02/2025

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
Ordinary Shares	09/02/2025		A		2,498(1)	A	$0.0	29,516	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. Effective as of September 2, 2025, the Board of Directors approved an annual restricted stock unit grant of 2,498 Ordinary Shares to each independent director. The RSU grant vests as to 1/4th of the Ordinary Shares each three months following the vesting start date of September 15, 2025, so as to be 100% vested on September 15, 2026, subject to continued service with the Company.

	By: /s/ Michael Morehead, Attorney-in-Fact For: Chenming Hu	09/04/2025
	** 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.

FAQ

What did AMBA director Chenming Hu receive according to the Form 4?

The filing shows an annual restricted stock unit (RSU) grant of 2,498 ordinary shares approved effective 09/02/2025.

When do the RSUs granted to Chenming Hu vest?

The RSUs vest in four equal quarterly installments starting on 09/15/2025 and are fully vested on 09/15/2026, subject to continued service.

How many shares does Chenming Hu beneficially own after the reported transaction?

The Form 4 reports 29,516 ordinary shares beneficially owned following the grant.

Was the Form 4 signed directly by Chenming Hu?

No; the Form 4 was executed by Michael Morehead, Attorney-in-Fact for Chenming Hu on 09/04/2025.

Does the Form 4 disclose any exercised options or derivative transactions for Chenming Hu?

No; Table II for derivative securities contains no entries, and only a non-derivative RSU grant is reported.