<SEC-DOCUMENT>0001254402-20-000001.txt : 20200506
<SEC-HEADER>0001254402-20-000001.hdr.sgml : 20200506
<ACCEPTANCE-DATETIME>20200506153044
ACCESSION NUMBER:		0001254402-20-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200505
FILED AS OF DATE:		20200506
DATE AS OF CHANGE:		20200506

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SIMMS JAMES A
		CENTRAL INDEX KEY:			0001254402

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-18277
		FILM NUMBER:		20852408

	MAIL ADDRESS:	
		STREET 1:		8383 SENECA TURNPIKE
		CITY:			NEW HARTFORD
		STATE:			NY
		ZIP:			13413

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			VICOR CORP
		CENTRAL INDEX KEY:			0000751978
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRONIC COMPONENTS, NEC [3679]
		IRS NUMBER:				042742817
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		25 FRONTAGE ROAD
		CITY:			ANDOVER
		STATE:			MA
		ZIP:			01810
		BUSINESS PHONE:		(978) 470-2900

	MAIL ADDRESS:	
		STREET 1:		25 FRONTAGE RD
		CITY:			ANDOVER
		STATE:			MA
		ZIP:			01810
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
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    <periodOfReport>2020-05-05</periodOfReport>

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        <issuerName>VICOR CORP</issuerName>
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                <value>Non Qualified Stock Option</value>
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    <footnotes>
        <footnote id="F1">Includes 179 shares acquired under the Vicor Corporation 2017 Employee Stock Purchase Plan on August 31, 2019.</footnote>
        <footnote id="F2">This transaction involved the exercise of  non-qualified stock options, the terms of  which provided for the purchase of  shares of common stock  possessing multi-year restrictions on their sale or transfer. As such, the exercise followed the sell-to-cover process, whereby a portion of the shares acquired through the exercise were sold in the open  market, with the proceeds used to fund the aggregate exercise price of the options and the income and employment taxes associated with the exercise. The balance of  the shares acquired through exercise that were delivered to the reporting person are subject to holding periods through the fifth anniversary of  the date of  this transaction.</footnote>
        <footnote id="F3">This stock option is exercisable in full.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Richard J. Nagel Jr. Attorney in fact for James A. Simms</signatureName>
        <signatureDate>2020-05-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
