Rimini Street Announces Fiscal First Quarter 2026 Financial and Operating Results page 1 Exhibit 99.1 FOR IMMEDIATE RELEASE Rimini Street Announces Fiscal First Quarter 2026 Financial and Operating Results First Quarter Financial Highlights Include: Remaining Performance Obligations (RPO) of $643.6 million, up 16.4% year over year Adjusted Calculated Billings of $92.2 million, up 22.9% year over year Adjusted Annualized Recurring Revenue (ARR) of $388.0 million, up 5.0% year over year LAS VEGAS, April 30, 2 ...