<SEC-DOCUMENT>0000921895-16-006295-index.html : 20161207
<SEC-HEADER>0000921895-16-006295.hdr.sgml : 20161207
<ACCEPTANCE-DATETIME>20161207181025
ACCESSION NUMBER:		0000921895-16-006295
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20161206
FILED AS OF DATE:		20161207
DATE AS OF CHANGE:		20161207

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			QUANTUM CORP /DE/
		CENTRAL INDEX KEY:			0000709283
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER STORAGE DEVICES [3572]
		IRS NUMBER:				942665054
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		224 AIRPORT PARKWAY
		STREET 2:		SUITE 300
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95110
		BUSINESS PHONE:		408 944 4000

	MAIL ADDRESS:	
		STREET 1:		224 AIRPORT PARKWAY
		STREET 2:		SUITE 300
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Value R GP LLC
		CENTRAL INDEX KEY:			0001575979

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040061

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212) 845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Value R LP
		CENTRAL INDEX KEY:			0001575972

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040062

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212)845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Principal Co GP LLC
		CENTRAL INDEX KEY:			0001517140

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040065

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212) 845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Principal Co LP
		CENTRAL INDEX KEY:			0001517139

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040066

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212) 845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Value LP
		CENTRAL INDEX KEY:			0001517137

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040069

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212) 845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Value & Opportunity C LP
		CENTRAL INDEX KEY:			0001571704

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040063

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212) 845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Starboard Value GP LLC
		CENTRAL INDEX KEY:			0001517138

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040068

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(212) 845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STARBOARD VALUE & OPPORTUNITY MASTER FUND LTD
		CENTRAL INDEX KEY:			0001373638

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040064

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		212-845-7906

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

	FORMER NAME:	
		FORMER CONFORMED NAME:	STARBOARD VALUE & OPPORTUNITY FUND LTD
		DATE OF NAME CHANGE:	20110404

	FORMER NAME:	
		FORMER CONFORMED NAME:	RAMIUS VALUE & OPPORTUNITY MASTER FUND LTD
		DATE OF NAME CHANGE:	20090730

	FORMER NAME:	
		FORMER CONFORMED NAME:	Starboard Value & Opportunity Master Fund Ltd
		DATE OF NAME CHANGE:	20060823

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STARBOARD VALUE & OPPORTUNITY S LLC
		CENTRAL INDEX KEY:			0001519812
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13449
		FILM NUMBER:		162040067

	BUSINESS ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		212-845-7977

	MAIL ADDRESS:	
		STREET 1:		777 THIRD AVENUE, 18TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
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Document 1 - file: form406297109a_12072016.html

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