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).

1. Name and Address of Reporting Person* Day Christopher (Last) (First) (Middle) 3101 JAY STREET (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) Director 10% Owner X Officer (give title below) Other (specify below) VP, Marketing
	3. Date of Earliest Transaction (Month/Day/Year) 06/16/2017
	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	06/16/2017		M		2,932	A	(1)	22,892	D
Ordinary Shares	06/16/2017		S(2)		1,526	D	$48.77	21,366	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
Restricted Stock Units	(1)	06/16/2017		M			876	(3)	09/15/2019(3)	Ordinary Shares	876	$0.0	7,893	D
Restricted Stock Units	(1)	06/16/2017		M			1,094	(4)	08/27/2023(4)	Ordinary Shares	1,094	$0.0	1,094	D
Restricted Stock Units	(1)	06/16/2017		M			962	(5)	09/07/2024(5)	Ordinary Shares	962	$0.0	4,813	D

Explanation of Responses:

1. Each restricted stock unit represents a contingent right to receive one share of Ambarella, Inc. Ordinary Shares.

2. Shares sold to pay tax obligations resulting from the vesting of restricted stock awards and restricted stock units.

3. The RSUs vest as to 1/10 of the RSUs on June 15, 2017 and 1/10 of the RSUs will vest each three months thereafter such that the RSUs are 100% vested on September 15, 2019.

4. The restricted stock units vest at the rate of 1/16 per quarter commencing on September 15, 2013.

5. The restricted stock units vest at the rate of 1/16 per quarter commencing on September 15, 2014.

	By: /s/ Michael Morehead, Attorney in Fact For: Christopher Day	06/20/2017
	** 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).
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