Quantum (QMCO) Form 4 Change in insider ownership

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

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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^*

Starboard Value LP

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
QUANTUM CORP /DE/ [ QTM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
01/22/2016

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	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
Common Stock, $0.01 Par Value(1)(2)	01/22/2016		S		1,137,730	D	$0.7252	13,479,254	I	By Starboard Value and Opportunity Master Fund Ltd(3)
Common Stock, $0.01 Par Value(1)(2)	01/22/2016		S		255,022	D	$0.7252	3,021,381	I	By Starboard Value and Opportunity S LLC(4)
Common Stock, $0.01 Par Value(1)(2)	01/22/2016		S		208,212	D	$0.7252	2,466,788	I	By Starboard Value and Opportunity C LP(5)
Common Stock, $0.01 Par Value(1)(2)	01/22/2016		S		399,036	D	$0.7252	4,727,577	I	By Managed Account of Starboard Value LP(6)
Common Stock, $0.01 Par Value(1)(2)	01/25/2016		S		1,706,594	D	$0.7	11,772,660	I	By Starboard Value and Opportunity Master Fund Ltd(3)
Common Stock, $0.01 Par Value(1)(2)	01/25/2016		S		382,534	D	$0.7	2,638,847	I	By Starboard Value and Opportunity S LLC(4)
Common Stock, $0.01 Par Value(1)(2)	01/25/2016		S		312,318	D	$0.7	2,154,470	I	By Starboard Value and Opportunity C LP(5)
Common Stock, $0.01 Par Value(1)(2)	01/25/2016		S		598,554	D	$0.7	4,129,023	I	By Managed Account of Starboard Value LP(6)

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

1. Name and Address of Reporting Person^*

Starboard Value LP

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Starboard Value GP LLC

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

STARBOARD VALUE & OPPORTUNITY S LLC

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Starboard Principal Co LP

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Starboard Principal Co GP LLC

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

STARBOARD VALUE & OPPORTUNITY MASTER FUND LTD

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Starboard Value & Opportunity C LP

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Starboard Value R LP

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

Starboard Value R GP LLC

(Last) (First) (Middle)

777 THIRD AVENUE

18TH FLOOR

(Street)

NEW YORK NY 10017

(City) (State) (Zip)

Explanation of Responses:

1. This Form 4 is filed jointly by Starboard Value and Opportunity Master Fund Ltd ("Starboard V&O Fund"), Starboard Value and Opportunity S LLC ("Starboard S LLC"), Starboard Value and Opportunity C LP ("Starboard C LP"), Starboard Value LP ("Starboard Value LP"), Starboard Value GP LLC ("Starboard Value GP"), Starboard Principal Co LP ("Principal Co"), Starboard Principal Co GP LLC ("Principal GP"), Starboard Value R LP ("Starboard R LP"), Starboard Value R GP LLC ("Starboard R GP"), Jeffrey C. Smith, Mark R. Mitchell and Peter A. Feld (collectively, the "Reporting Persons"). To enable all of the Reporting Persons to gain access to the Securities and Exchange Commission's electronic filing system (which only accepts a maximum of 10 joint filers per report), this report is the first of two identical reports relating to the same transactions being filed with the Securities and Exchange Commission.

2. Each Reporting Person may be deemed to be a member of a Section 13(d) group that owns more than 10% of the Issuer's outstanding shares of Common Stock. Each Reporting Person disclaims beneficial ownership of the shares of Common Stock reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such shares of Common Stock for purposes of Section 16 or for any other purpose.

3. Shares of Common Stock beneficially owned by Starboard V&O Fund. Starboard Value LP, as the investment manager of Starboard V&O Fund, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard V&O Fund. Each of Starboard Value GP, as the general partner of Starboard Value LP, Principal Co, as a member of Starboard Value GP, Principal GP, as the general partner of Principal Co, and Messrs. Smith, Mitchell and Feld, as members of Principal GP and as members of each of the Management Committee of Starboard Value GP and the Management Committee of Principal GP, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard V&O Fund.

4. Shares of Common Stock beneficially owned by Starboard S LLC. Starboard Value LP, as the manager of Starboard S LLC, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard S LLC. Each of Starboard Value GP, as the general partner of Starboard Value LP, Principal Co, as a member of Starboard Value GP, Principal GP, as the general partner of Principal Co, and Messrs. Smith, Mitchell and Feld, as members of Principal GP and as members of each of the Management Committee of Starboard Value GP and the Management Committee of Principal GP, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard S LLC.

5. Shares of Common Stock beneficially owned by Starboard C LP. Each of Starboard R LP, as the general partner of Starboard C LP, and Starboard R GP, as the general partner of Starboard R LP, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard C LP. Starboard Value LP, as the investment manager of Starboard C LP, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard C LP. Each of Starboard Value GP, as the general partner of Starboard Value LP, Principal Co, as a member of Starboard Value GP, Principal GP, as the general partner of Principal Co, and Messrs. Smith, Mitchell and Feld, as members of Principal GP and as members of each of the Management Committee of Starboard Value GP and the Management Committee of Principal GP, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard C LP.

6. Shares held in an account managed by Starboard Value LP. Starboard Value GP, as the general partner of Starboard Value LP, Principal Co, as a member of Starboard Value GP, Principal GP, as the general partner of Principal Co, and Messrs. Smith, Mitchell and Feld as members of Principal GP and as members of each of the Management Committee of Starboard Value GP and the Management Committee of Principal GP, may be deemed to be the beneficial owner of the shares of Common Stock beneficially owned by Starboard Value LP.

	Starboard Value LP; By: Starboard Value GP LLC; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Value and Opportunity Master Fund Ltd; By: Starboard Value LP; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Value and Opportunity S LLC; By: Starboard Value LP; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Value and Opportunity C LP; By: Starboard Value LP; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Value GP LLC; By: Starboard Principal Co LP; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Principal Co LP; By:Starboard Principal Co GP LLC; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Principal Co GP LLC; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Value R LP; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	Starboard Value R GP LLC; By: /s/ Jeffrey C. Smith, Authorized Signatory	01/26/2016
	** 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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