<SEC-DOCUMENT>0001280263-20-000021.txt : 20200319
<SEC-HEADER>0001280263-20-000021.hdr.sgml : 20200319
<ACCEPTANCE-DATETIME>20200319174530
ACCESSION NUMBER:		0001280263-20-000021
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200317
FILED AS OF DATE:		20200319
DATE AS OF CHANGE:		20200319

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Day Christopher
		CENTRAL INDEX KEY:			0001558685

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35667
		FILM NUMBER:		20729648

	MAIL ADDRESS:	
		STREET 1:		2975 SAN YSIDRO WAY
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95051

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMBARELLA INC
		CENTRAL INDEX KEY:			0001280263
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				980459628
		FISCAL YEAR END:			0131

	BUSINESS ADDRESS:	
		STREET 1:		3101 JAY STREET
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054
		BUSINESS PHONE:		408-734-8888

	MAIL ADDRESS:	
		STREET 1:		3101 JAY STREET
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
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    <periodOfReport>2020-03-17</periodOfReport>

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    <issuer>
        <issuerCik>0001280263</issuerCik>
        <issuerName>AMBARELLA INC</issuerName>
        <issuerTradingSymbol>AMBA</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>Day Christopher</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3101 JAY STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Marketing</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
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                <value>Ordinary Shares</value>
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            <transactionDate>
                <value>2020-03-17</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>4698</value>
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                <transactionPricePerShare>
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                <footnoteId id="F4"/>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
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                    <value>668</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.0</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            <exerciseDate>
                <footnoteId id="F6"/>
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                <value>2022-03-15</value>
                <footnoteId id="F6"/>
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                    <value>5341</value>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit represents a contingent right to receive one share of Ambarella, Inc. Ordinary Shares.</footnote>
        <footnote id="F2">Includes 193 shares acquired under the Company's employee stock purchase plan on March 16, 2020.</footnote>
        <footnote id="F3">Shares sold to pay tax obligations resulting from the vesting of restricted stock units.</footnote>
        <footnote id="F4">On March 28, 2017, reporting person was granted an RSU award covering a target of 3,758 ordinary shares (the &quot;Target RSU Number&quot;), subject to satisfaction of predetermined, performance-based vesting criteria that could result in 0% - 150% of the Target RSU Number becoming eligible to vest, subject to certain adjustments. On February 26, 2018, the Company's Board of Directors determined the performance criteria for the RSUs had been satisfied at a level that resulted in 100% of the Target RSU Number becoming eligible for time-based vesting. Pursuant to time-based vesting requirements, 100% of the award would vest on March 15, 2020, subject to possible adjustment based on a total stockholder return (&quot;TSR&quot;) performance metric covering the period of February 1, 2017 to January 31, 2020 (the &quot;TSR Period&quot;). As a result of the Company's TSR performance over the TSR Period, the RSUs eligible to vest were reduced by 25%. A total of 2,819 ordinary shares were delivered to reporting person.</footnote>
        <footnote id="F5">The restricted stock units vest at the rate of 1/12 per quarter commencing on June 15, 2018.</footnote>
        <footnote id="F6">The restricted stock units vest at the rate of 1/12 per quarter commencing on March 15, 2019.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Michael Morehead, Attorney-in-Fact For: Christopher Day</signatureName>
        <signatureDate>2020-03-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
