# EDGAR Filing Document

**Accession Number:** 0000709283
**File Stem:** 0000709283-25-000087
**Filing Date:** 2025-12
**Character Count:** 3730
**Document Hash:** f159e7bb75b091e319737a71991165be
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000709283-25-000087.hdr.sgml**: 20251202

**ACCESSION NUMBER**: 0000709283-25-000087

**CONFORMED SUBMISSION TYPE**: DEFA14A

**PUBLIC DOCUMENT COUNT**: 8

**FILED AS OF DATE**: 20251202

**DATE AS OF CHANGE**: 20251202

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** QUANTUM CORP /DE/
- **CENTRAL INDEX KEY:** 0000709283
- **STANDARD INDUSTRIAL CLASSIFICATION:** COMPUTER STORAGE DEVICES [3572]
- **ORGANIZATION NAME:** 06 Technology
- **EIN:** 942665054
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 0331

**FILING VALUES:**
- **FORM TYPE:** DEFA14A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-13449
- **FILM NUMBER:** 251543517

**BUSINESS ADDRESS:**
- **STREET 1:** 224 AIRPORT PARKWAY
- **STREET 2:** SUITE 550
- **CITY:** SAN JOSE
- **STATE:** CA
- **ZIP:** 95110
- **BUSINESS PHONE:** 408 944 4000

**MAIL ADDRESS:**
- **STREET 1:** 224 AIRPORT PARKWAY
- **STREET 2:** SUITE 550
- **CITY:** SAN JOSE
- **STATE:** CA
- **ZIP:** 95110

    

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

**SCHEDULE 14A** 

**Proxy Statement Pursuant to Section 14(a) of the Securities**

**Exchange Act of 1934 (Amendment No.)**

Filed by the Registrant ☒ Filed by a party other than the Registrant ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material Pursuant to Section 240.14a-12

![qlogo.jpg](qlogo.jpg)

**Quantum Corporation**

(Name of Registrant as Specified in its Charter)

____________________________________________________________________________

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

☒ No fee required.

☐ Fee paid previously with preliminary materials.

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

    

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[Social media posts first used on or after December 2, 2025]

![image_0.jpg](image_0.jpg)

Voting your Quantum shares is quick and easy.

Please submit your vote before the Dec 15 deadline (11:59 PM ET) ahead of the Dec 16 Annual Meeting.

Vote now: [link to 2025 Annual Meeting landing page] 

#QuantumCorp #ShareholderVote #QMCO

![image_1.jpg](image_1.jpg)

Don't forget to vote!

Quantum's voting cut-off is **Dec 15 at 11:59 PM ET** ahead of the **Dec 16 Annual Meeting.** 

<br>[link to 2025 Annual Meeting landing page]

#QuantumCorp #ShareholderVote #QMCO

------

![image_2.jpg](image_2.jpg)

A reminder for Quantum shareholders:<br>Please submit your vote ahead of the **Dec 15, 11:59 PM ET** cut-off.

<br>The Annual Meeting will be held **Dec 16.**

Vote now: [link to 2025 Annual Meeting landing page]

#QuantumCorp #ShareholderVote #QMCO

![image_3.jpg](image_3.jpg)

Quantum shareholders: please vote your shares by **11:59 PM ET on Dec 15** in advance of the **Dec 16 Annual Meeting.** 

<br>Vote here → [link to 2025 Annual Meeting landing page]

#QuantumCorp #ShareholderVote #QMCO

------

![image_4.jpg](image_4.jpg)

Quantum shareholders are reminded to vote their shares ahead of the Dec 15 at 11:59 PM ET voting deadline.

<br>The Annual Meeting will be held on Dec 16.

Vote here: [link to 2025 Annual Meeting landing page]

#QuantumCorp #ShareholderVote #QMCO

![image_5.jpg](image_5.jpg)

A reminder to Quantum shareholders: Please submit your vote before the Dec 15 (11:59 PM ET) cut-off to participate in the Dec 16 Annual Meeting.

<br>Vote here: [link to 2025 Annual Meeting landing page]

#QuantumCorp #ShareholderVote #QMCO

<br>