UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D
(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO
§ 240.13d-2(a)

(Amendment No. 3)1

Quantum Corporation
(Name of Issuer)

Common Stock, $.01 par value per share
(Title of Class of Securities)

747906 20 4
(CUSIP Number)
 
ERIC SINGER
VIEX CAPITAL ADVISORS, LLC
825 Third Avenue, 33rd Floor
New York, New York 10022
 
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

April 28, 2016
(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box ¨.

Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See § 240.13d-7 for other parties to whom copies are to be sent.


_______________
1              The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).
 
 
 
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
VIEX Opportunities Fund, LP - Series One*
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
WC
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
7,407,865
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
7,407,865
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
7,407,865
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
2.8%
14
TYPE OF REPORTING PERSON
 
PN
 
* This Series One is part of a series of VIEX Opportunities Fund, LP, a Delaware series limited partnership.
 
 
2
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
VIEX Opportunities Fund, LP - Series Two*
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
WC
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
1,413,191
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
1,413,191
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
1,413,191
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
Less than 1%
14
TYPE OF REPORTING PERSON
 
PN
 
* This Series Two is part of a series of VIEX Opportunities Fund, LP, a Delaware series limited partnership.
 
 
3
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
VIEX Special Opportunities Fund III, LP
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
WC
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
17,420,940
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
17,420,940
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
17,420,940
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
6.6%
14
TYPE OF REPORTING PERSON
 
PN

 
4
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
VIEX GP, LLC
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
AF
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
8,821,056
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
8,821,056
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
8,821,056
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
3.3%
14
TYPE OF REPORTING PERSON
 
OO

 
5
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
VIEX Special Opportunities GP III, LLC
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
AF
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
17,420,940
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
17,420,940
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
17,420,940
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
6.6%
14
TYPE OF REPORTING PERSON
 
OO

 
6
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
VIEX Capital Advisors, LLC
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
AF
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
26,241,996
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
26,241,996
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
26,241,996
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
9.9%
14
TYPE OF REPORTING PERSON
 
IA

 
7
 
CUSIP NO. 747906 20 4
 
1
NAME OF REPORTING PERSON
 
Eric Singer
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
  (a) o
  (b) o
3
SEC USE ONLY
 
4
SOURCE OF FUNDS
 
AF
5
CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
 
¨
6
CITIZENSHIP OR PLACE OF ORGANIZATION
 
USA
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH
7
SOLE VOTING POWER
 
- 0 -
8
SHARED VOTING POWER
 
26,241,996
9
SOLE DISPOSITIVE POWER
 
- 0 -
10
SHARED DISPOSITIVE POWER
 
26,241,996
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
26,241,996
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES
 
o
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
9.9%
14
TYPE OF REPORTING PERSON
 
IN

 
8
 
CUSIP NO. 747906 20 4
 
The following constitutes Amendment No. 3 to the Schedule 13D filed by the undersigned (the “Amendment No. 3”). This Amendment No. 3 amends the Schedule 13D as specifically set forth herein.
 
Item 4.
Purpose of Transaction.
 
Item 4 is hereby amended to add the following:
 
On April 28, 2016, the Reporting Persons delivered a letter to the Issuer’s Board of Directors (the “Board”) highlighting the Issuer’s track record for poor performance and the destruction of stockholder value that has occurred as a result. The Reporting Persons stated that the most effective way to improve the Issuer’s performance, address credibility issues and restore investor confidence is to reconstitute the Board. The Reporting Persons made clear that they intend to exercise all rights available to them to improve the Issuer’s performance, including the right to nominate a slate of highly-qualified directors at the Issuer’s upcoming Annual Meeting. A copy of the letter is attached hereto as Exhibit 99.1 and is incorporated herein by reference.
 
Item 7.
Material to be Filed as Exhibits.
 
Item 7 is hereby amended to add the following exhibit:
 
 
99.1
Letter to the Board of Directors, dated April 28, 2016.
 
 
9
 
CUSIP NO. 747906 20 4
 
SIGNATURES
 
After reasonable inquiry and to the best of his knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.
 
Dated:  April 28, 2016

 
VIEX Opportunities Fund, LP – Series One
   
 
By:
VIEX GP, LLC
General Partner
   
 
By:
 /s/ Eric Singer
   
Name:
Eric Singer
   
Title:
Managing Member


 
VIEX Opportunities Fund, LP – Series Two
   
 
By:
VIEX GP, LLC
General Partner
   
 
By:
 /s/ Eric Singer
   
Name:
Eric Singer
   
Title:
Managing Member


 
VIEX GP, LLC
   
 
By:
 /s/ Eric Singer
   
Name:
Eric Singer
   
Title:
Managing Member


 
VIEX Special Opportunities Fund III, LP
   
 
By:
VIEX Special Opportunities GP III, LLC
General Partner
   
 
By:
 /s/ Eric Singer
   
Name:
Eric Singer
   
Title:
Managing Member


 
VIEX Special Opportunities GP III, LLC
     
 
By:
 /s/ Eric Singer
   
Name:
Eric Singer
   
Title:
Managing Member

 
10
 
CUSIP NO. 747906 20 4

 
VIEX Capital Advisors, LLC
   
 
By:
 /s/ Eric Singer
   
Name:
Eric Singer
   
Title:
Managing Member

  /s/ Eric Singer
 
Eric Singer

 
11