QUANTUM CORP /DE/ — Director's Dealing 2011

May 16, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: QUANTUM CORP /DE/ (QTM)
CIK: 0000709283
Period of Report: 2011-05-16

Reporting Person: BRITTS WILLIAM C (EVP, Sales, Marketing & Serv.)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-05-16	Common Stock	S	55000	$2.9247	Disposed	433453	Direct

Footnotes

F1: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 1, 2011.

F2: The sale price reported in column 4 of Table I represents the weighted average sale price of the shares sold ranging from $2.91 to $2.93 per share. Upon request by the Commission staff, the Issuer, or a security holder of the Issuer, the reporting person will provide full information regarding the number of shares sold at each separate price.