UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): September 22, 2025

Ciena Corporation

(Exact name of registrant as specified in its charter)

Commission File Number: 001-36250

Delaware

(State or other jurisdiction of incorporation)

7035 Ridge Road, Hanover, MD

(Address of principal executive offices)

23-2725311

(IRS Employer Identification No.)

21076

(Zip Code)

Registrant's telephone number, including area code: (410) 694-5700

Not Applicable

(Former name or former address, if changed since last report)


Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):
☐			Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐			Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐			Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐			Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))


Securities registered pursuant to Section 12(b) of the Act:
Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common stock, $0.01 par value	CIEN	New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 8.01 – OTHER EVENTS

On September 22, 2025, Ciena Corporation ("Ciena") issued a press release announcing that it has entered into a definitive agreement to acquire privately-held Nubis Communications, Inc., which specializes in high-performance, ultra-compact, low-power optical and electrical interconnects tailored to support artificial intelligence (AI) workloads. The transaction is expected to close during Ciena’s fiscal fourth quarter 2025 and is subject to customary closing conditions. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein.

This Current Report on Form 8-K contains forward-looking statements that are based on management’s current expectations, forecasts, information and assumptions. These statements involve inherent risks and uncertainties. Actual results or outcomes may differ materially from those stated or implied in the forward-looking statements because of risks and uncertainties, including the risks that the acquisition may not close when expected, or at all, that problems may arise in successfully integrating the acquired business, that the acquisition may fail to achieve its expected benefits, and those risks and uncertainties detailed in Ciena’s most recent annual and quarterly reports filed with the Securities and Exchange Commission. Forward-looking statements include statements regarding Ciena's expectations, beliefs, intentions or strategies, and can be identified by words such as "anticipate," "believe," "could," "estimate," "expect," "intend," "may," and "will," and similar words and expressions. Ciena assumes no obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise, except to the extent required by law.

Item 9.01 Financial Statements and Exhibits.


Exhibit Number			Description of Document

99.1			Text of Press Release dated September 22, 2025.
104			Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.


	Ciena Corporation


Date: September 22, 2025	By:	/s/ Sheela Kosaraju
		Sheela Kosaraju
		Senior Vice President, General Counsel and Assistant Secretary

CIENA CORP 8-K