Ciena(CIEN) - 2025 Q4 - Annual Report

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d)OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended November 1, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)OF THE SECURITIES EXCHANGE ACT OF 1934 Securities registered pursuant to Section 12(b) of the Act: For the transition period from to Commission file number 001-36250 Ciena Corporation (Exact name of registrant as speci ...