# EDGAR Filing Document

**Accession Number:** 0001411509
**File Stem:** 0001628280-26-041759
**Filing Date:** 2026-6
**Character Count:** 8809
**Document Hash:** ce066c0868e2c72e5c02dcb20f64fb6f
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001628280-26-041759.hdr.sgml**: 20260608

**ACCESSION NUMBER**: 0001628280-26-041759

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260601

**FILED AS OF DATE**: 20260608

**DATE AS OF CHANGE**: 20260608

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** FICHTHORN JOHN
- **CENTRAL INDEX KEY:** 0001411509

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-13449
- **FILM NUMBER:** 261074456

**MAIL ADDRESS:**
- **STREET 1:** C/O DIALECTIC CAPITAL MANAGEMENT, LLC
- **STREET 2:** 17 STATE STREET, SUITE 3930
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10004
**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>FICHTHORN JOHN<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>2026-06-01 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **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 | 2026-06-04 |  | C<sup>(1)(2)</sup> |  | 11020645 | A | $5.194 | 11020645<sup>(1)(2)</sup> | I | by Dialectic Technology SPV LLC<sup>(3)</sup> |
| Common Stock | 2026-06-04 |  | A<sup>(1)(2)</sup> |  | 3083975 | A | $5.194 | 14104620<sup>(1)(2)(4)</sup> | I | by Dialectic Technology SPV LLC<sup>(3)</sup> |
| Common Stock |  |  |  |  |  |  |  | 28896<sup>(5)</sup> | 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 |
| Warrant (right to buy) | 5.194<sup>(6)</sup> | 2026-06-01<sup>(6)</sup> |  | J |  | 105911<sup>(6)</sup> |  | 2026-06-01<sup>(6)</sup> | 2031-06-01<sup>(6)</sup> | Common Stock | 105911<sup>(6)</sup> | <sup>(6)</sup> | 105911<sup>(6)</sup> | I | by Dialectic Technology SPV LLC<sup>(3)</sup> |
| Convertible Notes | 5.194<sup>(1)(2)</sup> | 2026-06-04 |  | C |  |  | 57241228<sup>(1)(2)</sup> | 2025-12-18 | <sup>(1)(2)</sup> | Common Stock | 11020645<sup>(1)(2)</sup> | <sup>(1)(3)</sup> | 0<sup>(1)(3)</sup> | I | by Dialectic Technology SPV LLC<sup>(3)</sup> |

---

### Footnotes:

(1) On June 4, 2026 (the "Closing Date"), pursuant to a Conversion Agreement dated June 1, 2026 (the "Conversion Agreement"), by and among, among others, the Issuer and Dialectic (as defined below), Dialectic converted $57,241,228.00 of the previously issued 10.00% PIK senior secured convertible notes due 2028 (the "Convertible Notes"), consisting of the entire principal amount and all accrued and unpaid interest thereon, subject to certain conditions set forth in the Conversion Agreement (the "Conversion").

(2) In connection with the Conversion, on the Closing Date, the Convertible Notes were cancelled, and the Issuer issued to Dialectic 11,020,645 shares of Common Stock (as defined below).

(3) These securities are held directly by Dialectic, a 10% holder of the Issuer, and indirectly by John Fichthorn. Mr. Fichthorn is the Manager of Dialectic Technology Manager LLC, the Manager of Dialectic. The Reporting Person disclaims beneficial ownership of these securities, except to the extent of the Reporting Person's pecuniary interest therein, if any.

(4) On the Closing Date, as consideration for the Conversion, the Issuer issued to Dialectic, (i) 3,083,975 additional shares of Common Stock (the "Consideration Shares"), which represents the quotient of (A) approximately $13.0 million, the present value of nominal PIK interest that would accrue on the Convertible Notes from the Closing Date to the maturity date thereof, discounted at a rate of 11%, plus (B) approximately $3.0 million, the Term Loan Deferred Cash Interest Amount (as defined in the Credit Agreement) owed to Dialectic, divided by $5.194.

(5) Includes 1,625 shares of Common Stock received by the Reporting Report as a result of a distribution of assets from a trust on June 1, 2026, which shares previously held indirectly by such trust were previously inadvertently omitted.

(6) On June 1, 2026 ("Issuance Date"), the Issuer issued to Dialectic Technology SPV LLC ("Dialectic") a warrant (the "Conversion Warrant") to purchase 105,911 (as may be adjusted pursuant to the Conversion Warrant) shares of common stock, par value $0.01 per share of the Issuer (the "Common Stock"), at an exercise price equal to $5.194 per share (as adjusted from time to time in accordance with the Conversion Warrant) on or after the Issuance Date and until the date that is five (5) years from the Issuance Date.

**Signature:** Tara Ilges, attorney-in-fact for John A. Fichthorn  
**Date:** 2026-06-08

### 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.**