Exhibit 99.1 Quantum Reports Fiscal First Quarter 2026 Financial Results Leadership Team Executing Steps to Improve Operational and Financial Performance. SAN JOSE, Calif. — September 10, 2025 — Quantum Corporation (Nasdaq: QMCO) ("Quantum" or the "Company"), today announced financial results for its fiscal first quarter 2026 ended June 30, 2025. Management Commentary "Since my recent appointment in June, I've been dedicating a significant portion of my time toward conducting in-depth reviews of the busines ...