# EDGAR Filing Document

**Accession Number:** 0001979364
**File Stem:** 0001979364-25-000006
**Filing Date:** 2025-10
**Character Count:** 7123
**Document Hash:** 42fc70d4d86653bac1423544702e8817
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001979364-25-000006.hdr.sgml**: 20251003

**ACCESSION NUMBER**: 0001979364-25-000006

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251001

**FILED AS OF DATE**: 20251003

**DATE AS OF CHANGE**: 20251003

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Nash Laura A.
- **CENTRAL INDEX KEY:** 0001979364

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-13449
- **FILM NUMBER:** 251374586

**MAIL ADDRESS:**
- **STREET 1:** C/O QUANTUM CORPORATION
- **STREET 2:** 224 AIRPORT PARKWAY, SUITE 550
- **CITY:** SAN JOSE
- **STATE:** CA
- **ZIP:** 95110
**ISSUER**: 

**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

**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**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Nash Laura A.<br><sub>(Last) (First) (Middle)</sub><br>C/O QUANTUM CORPORATION<br>10770 E. BRIARWOOD AVE<br><sub>(Street)</sub><br>CENTENNIAL, CO 80112<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2025-10-01 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_Chief Accounting Officer_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>QUANTUM CORP /DE/ [ QMCO ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2025-10-01 |  | A |  | 500 | A | $0 | 11868 | D |  |
| Common Stock | 2025-10-01 |  | S |  | 118<sup>(1)</sup> | D | 9.91<sup>(2)</sup> | 11750 | D |  |
| Common Stock | 2025-10-02 |  | S |  | 611<sup>(3)</sup> | D | 10.86<sup>(4)</sup> | 11139 | D |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

---

### Footnotes:

(1) Represents the number of shares automatically sold on a non-discretionary basis, to cover tax withholding obligations in connection with the vesting of performance-based stock units granted on July 1, 2023.

(2) Represents a weighted average price. These shares were sold as part of block trades for multiple security holders of the issuer on October 1, 2025, at a price ranging from $9.9026 to $9.9118. The reporting person undertakes to provide upon request by the Securities and Exchange Commission, the issuer, or a securityholder of the issuer detailed information regarding the number of shares sold and the prices at which the transactions were executed.

(3) Represents the number of shares automatically sold on a non-discretionary basis, to cover tax withholding obligations in connection with the vesting of restricted stock units granted on October 1, 2024.

(4) Represents a weighted average price. These shares were sold as part of block trades for multiple security holders of the issuer on October 2, 2025, at a price ranging from $10.85 to $10.87. The reporting person undertakes to provide upon request by the Securities and Exchange Commission, the issuer, or a securityholder of the issuer detailed information regarding the number of shares sold and the prices at which the transactions were executed.

**Signature:** /s/ Tara Ilges, Attorney-in-Fact for Laura A. Nash  
**Date:** 2025-10-03

### Remarks:

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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**