171779AE1

• The notes mature on September 15, 2031, with an initial conversion rate of 1.3393 shares per $1,000 principal (initial conversion price ~$746.66 per share).
• Net proceeds were approximately $2.72 billion; Ciena used ~$140.0 million to repurchase ~0.3 million shares at $466.67 per share and ~$1.14 billion to repay its existing senior secured term loan.
• Ciena entered into convertible note hedge and warrant transactions, increasing the effective conversion price to $1,000 per share, and amended its credit agreement to extend the revolving facility maturity to October 24, 2030.
• The notes and warrants were sold in unregistered transactions under Section 4(a)(2) and Rule 144A; the maximum shares issuable under warrants is 7,700,978.

1.01 Entry into a Material Definitive Agreement · 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement · 3.02 Unregistered Sales of Equity Securities · 8.01 Other Events · 9.01 Financial Statements and Exhibits

• The notes will be guaranteed on a senior unsecured basis by each wholly-owned domestic subsidiary that guarantees its 4.00% senior notes due 2030 or any refinancing.
• Initial purchasers will have an option to buy up to an additional $300.0 million principal amount of notes within a 13-day period starting on the initial closing date.
• Proceeds will be used to pay the net cost of convertible note hedge transactions, repurchase up to $140 million of common stock, repay approximately $1.14 billion of the existing term loan, and for general corporate purposes.
• The company expects to enter into a Credit Agreement Amendment to extend the revolving facility maturity to October 24, 2030, and adjust interest rate terms, conditioned on repayment of the existing term loan.

8.01 Other Events · 9.01 Financial Statements and Exhibits

• Adjusted EPS was $1.64, up 290% from $0.42 in the prior-year quarter; GAAP diluted EPS was $1.49.
• Adjusted gross margin expanded to 44.9% from 41.0% year-over-year; GAAP gross margin was 44.0%.
• Company guides Q3 FY2026 revenue to $1.625 billion ± $50 million and raises FY2026 revenue guidance to $6.3 billion ± $100 million.
• Optical Networking segment revenue was $1.10 billion, up from $773.6 million year-over-year.

2.02 Results of Operations and Financial Condition · 9.01 Financial Statements and Exhibits

• Directors Joanne B. Olsen, Mary G. Puma, and Gary B. Smith were each elected to three-year terms expiring at the 2029 annual meeting.
• Stockholders ratified PricewaterhouseCoopers LLP as independent auditor for fiscal 2026, with 123,082,607 votes for and 5,389,750 against.
• The advisory say-on-pay proposal on named executive officer compensation passed with 114,515,974 votes for and 5,360,579 against.
• Proposals 2 and 3 were approved by majority of shares present, with abstentions counted as against and broker non-votes having no effect.

5.07 Submission of Matters to a Vote of Security Holders

• Fiscal first quarter 2026 revenue was $1.43 billion, up 33% year-over-year from $1.07 billion in fiscal Q1 2025.
• GAAP gross margin was 43.8% and non-GAAP gross margin was 44.7%, both roughly flat year-over-year.
• Company guides fiscal Q2 2026 revenue to $1.5 billion plus or minus $50 million.
• Fiscal year 2026 revenue guidance raised to $5.9 billion to $6.3 billion, a 28% increase year-over-year at the midpoint.

2.02 Results of Operations and Financial Condition · 9.01 Financial Statements and Exhibits

• GAAP diluted EPS was $0.13 for Q4 2025 and $0.85 for fiscal year 2025; adjusted (non-GAAP) diluted EPS was $0.91 and $2.64, respectively.
• Q4 2025 GAAP gross margin was 42.7% and non-GAAP gross margin was 43.4%; operating margin was 0.8% GAAP and 13.2% non-GAAP.
• Guidance: Q1 FY2026 revenue of $1.35B-$1.43B; FY2026 revenue of $5.7B-$6.1B, with non-GAAP operating margin of 17% +/- 1%.
• Three customers each represented 10%+ of Q4 revenue, totaling 43.6% of revenue; company repurchased ~0.7M shares for $84.5M in Q4.

2.02 Results of Operations and Financial Condition · 9.01 Financial Statements and Exhibits

• Effective November 30, 2025, Ciena entered into revised change in control severance agreements with its executive officers, including CEO Gary B. Smith, CFO Marc D. Graff, and others.
• The new agreements have fixed terms through November 30, 2028, replacing the prior agreements that expired on November 30, 2025.
• Changes include clarifying that the agreements do not limit Ciena's Executive Compensation Clawback Policy and clarifying equity treatment under Section 409A.
• Severance benefits and other terms are substantially equivalent to the prior form of agreements.
• The agreements cover named executive officers including Dino DiPerna, Jason M. Phipps, and David M. Rothenstein.

5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements

• On October 7, 2025, Ciena Corporation completed its acquisition of privately-held Nubis Communications, Inc.
• The acquisition was reported under Item 8.01 (Other Events) as a material event not otherwise specified in the form.
• The filing does not disclose the purchase price or other financial terms of the transaction.

8.01 Other Events