SC 13G 1 filing.txt DOC ONE SCHEDULE 13G Amendment No. 0 Quantum Corporation common stock Cusip #747906204 Cusip #747906204 Item 1: Reporting Person - FMR LLC Item 4: Delaware Item 5: 865,501 Item 6: 0 Item 7: 13,220,961 Item 8: 0 Item 9: 13,220,961 Item 11: 5.956% Item 12: HC Cusip #747906204 Item 1: Reporting Person - Edward C. Johnson 3d Item 4: United States of America Item 5: 0 Item 6: 0 Item 7: 13,220,961 Item 8: 0 Item 9: 13,220,961 Item 11: 5.956% Item 12: IN SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b) Item 1(a). Name of Issuer: Quantum Corporation Item 1(b). Name of Issuer's Principal Executive Offices: 1650 Technology Drive Suite 700 San Jose, CA 95110 Item 2(a). Name of Person Filing: FMR LLC Item 2(b). Address or Principal Business Office or, if None, Residence: 82 Devonshire Street, Boston, Massachusetts 02109 Item 2(c). Citizenship: Not applicable Item 2(d). Title of Class of Securities: common stock Item 2(e). CUSIP Number: 747906204 Item 3. This statement is filed pursuant to Rule 13d-1(b) or 13d-2(b) and the person filing, FMR LLC, is a parent holding company in accordance with Section 240.13d-1(b)(ii)(G). (Note: See Item 7). Item 4. Ownership (a) Amount Beneficially Owned: 13,220,961 (b) Percent of Class: 5.956% (c) Number of shares as to which such person has: (i) sole power to vote or to direct the vote: 865,501 (ii) shared power to vote or to direct the vote: 0 (iii) sole power to dispose or to direct the disposition of: 13,220,961 (iv) shared power to dispose or to direct the disposition of: 0 Item 5. Ownership of Five Percent or Less of a Class. Not applicable. Item 6. Ownership of More than Five Percent on Behalf of Another Person. Various persons have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the common stock of Quantum Corporation. No one person's interest in the common stock of Quantum Corporation is more than five percent of the total outstanding common stock. Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company. See attached Exhibit A. Item 8. Identification and Classification of Members of the Group. Not applicable. See attached Exhibit A. Item 9. Notice of Dissolution of Group. Not applicable. Item 10. Certification. By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purpose or effect. Signature After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. February 11, 2011 Date /s/ Scott C. Goebel Signature Scott C. Goebel Duly authorized under Power of Attorney effective as of June 1, 2008 by and on behalf of FMR LLC and its direct and indirect subsidiaries SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b) Pursuant to the instructions in Item 7 of Schedule 13G, Fidelity Management & Research Company ("Fidelity"), 82 Devonshire Street, Boston, Massachusetts 02109, a wholly- owned subsidiary of FMR LLC and an investment adviser registered under Section 203 of the Investment Advisers Act of 1940, is the beneficial owner of 12,341,260 shares or 5.560% of the common stock outstanding of Quantum Corporation ("the Company") as a result of acting as investment adviser to various investment companies registered under Section 8 of the Investment Company Act of 1940. The number of shares of common stock of Quantum Corporation owned by the investment companies at December 31, 2010 included 103,860 shares of common stock resulting from the assumed conversion of $450,000 principal amount of QUANTUM CORP CV 3.5 11/15 (230.8003 shares of common stock for each $1,000 principal amount of debenture). Edward C. Johnson 3d and FMR LLC, through its control of Fidelity, and the funds each has sole power to dispose of the 12,341,260 shares owned by the Funds. Members of the family of Edward C. Johnson 3d, Chairman of FMR LLC, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders' voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders' voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. Neither FMR LLC nor Edward C. Johnson 3d, Chairman of FMR LLC, has the sole power to vote or direct the voting of the shares owned directly by the Fidelity Funds, which power resides with the Funds' Boards of Trustees. Fidelity carries out the voting of the shares under written guidelines established by the Funds' Boards of Trustees. Pyramis Global Advisors, LLC ("PGALLC"), 900 Salem Street, Smithfield, Rhode Island, 02917, an indirect wholly-owned subsidiary of FMR LLC and an investment adviser registered under Section 203 of the Investment Advisers Act of 1940, is the beneficial owner of 775,489 shares or 0.349% of the outstanding common stock of Quantum Corporation as a result of its serving as investment adviser to institutional accounts, non-U.S. mutual funds, or investment companies registered under Section 8 of the Investment Company Act of 1940 owning such shares. The number of shares of common stock of Quantum Corporation owned by the institutional account(s) at December 31, 2010 included 775,489 shares of common stock resulting from the assumed conversion of $3,360,000 principal amount of QUANTUM CORP CV 3.5 11/15 (230.8003 shares of common stock for each $1,000 principal amount of debenture). Edward C. Johnson 3d and FMR LLC, through its control of PGALLC, each has sole dispositive power over 775,489 shares and sole power to vote or to direct the voting of 775,489 shares of common stock owned by the institutional accounts or funds advised by PGALLC as reported above. Pyramis Global Advisors Trust Company ("PGATC"), 900 Salem Street, Smithfield, Rhode Island, 02917, an indirect wholly-owned subsidiary of FMR LLC and a bank as defined in Section 3(a)(6) of the Securities Exchange Act of 1934, is the beneficial owner of 104,212 shares or 0.047% of the outstanding common stock of the Quantum Corporation as a result of its serving as investment manager of institutional accounts owning such shares. The number of shares of common stock of Quantum Corporation owned by the institutional account(s) at December 31, 2010 included 90,012 shares of common stock resulting from the assumed conversion of $390,000 principal amount of QUANTUM CORP CV 3.5 11/15 (230.8003 shares of common stock for each $1,000 principal amount of debenture). Edward C. Johnson 3d and FMR LLC, through its control of Pyramis Global Advisors Trust Company, each has sole dispositive power over 104,212 shares and sole power to vote or to direct the voting of 90,012 shares of common stock owned by the institutional accounts managed by PGATC as reported above. SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b) RULE 13d-1(f)(1) AGREEMENT The undersigned persons, on February 11, 2011, agree and consent to the joint filing on their behalf of this Schedule 13G in connection with their beneficial ownership of the common stock of Quantum Corporation at December 31, 2010. FMR LLC By /s/ Scott C. Goebel Scott C. Goebel Duly authorized under Power of Attorney effective as of June 1, 2008, by and on behalf of FMR LLC and its direct and indirect subsidiaries Edward C. Johnson 3d By /s/ Scott C. Goebel Scott C. Goebel Duly authorized under Power of Attorney effective as of June 1, 2008, by and on behalf of Edward C. Johnson 3d Fidelity Management & Research Company By /s/ Scott C. Goebel Scott C. Goebel Senior V.P. and General Counsel