8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

June 29, 2007

Date of Report (Date of earliest event reported)

SYCAMORE NETWORKS, INC.

(Exact name of registrant as specified in its charter)

Delaware	000-27273	04-3410558
(State or other jurisdiction of incorporation)	(Commission file number)	(IRS Employer Identification No.)

220 Mill Road

Chelmsford, MA 01824

(Address of principal executive offices)

(Zip code)

Registrant’s telephone number, including area code: (978) 250-2900

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:

¨ 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))

ITEM 2.05 Costs Associated with Exit or Disposal Activities

On June 29, 2007, Sycamore Networks, Inc. (the “Registrant”) announced a workforce realignment that will include a reduction of 46 employees or approximately 10% of the Registrant’s total workforce. These actions are designed to better align development resources with future growth opportunities, further improve operational efficiencies, and capitalize on additional acquisition synergies. This realignment is expected to be completed by the end of July 2007.

Based on preliminary information and assessments, the Registrant currently expects to incur aggregate pre-tax restructuring and asset impairment charges in the range of $4.0 million to $7.0 million, the majority of which the Registrant expects will be recorded in the six-month period ending October 27, 2007. These charges are expected to consist of:

• approximately $1.5 to $2.0 million of severance charges with respect to terminated employees; and

• approximately $2.5 to $5.0 million of facility related consolidation charges associated with the Registrant’s Moorestown, New Jersey location.

The Registrant’s press release announcing this workforce realignment is attached as Exhibit 99.1 to this Current Report on Form 8-K and incorporated herein by reference.

Item 9.01: Financial Statements and Exhibits

(d) Exhibits

99.1 Press Release, dated June 29, 2007, of Sycamore Networks, Inc.

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.

Sycamore Networks, Inc.

By: /s/ Alan R. Cormier

Alan R. Cormier

General Counsel and Secretary

Dated: June 29, 2007

EX-99.1

Exhibit 99.1

CONTACT: Press Inquiries Scott Larson Sycamore Networks, Inc. 978-250-3433 scott.larson@sycamorenet.com Investor Inquiries Investor Relations Sycamore Networks, Inc. 978-250-3460 investor.info@sycamorenet.com

SYCAMORE ANNOUNCES WORKFORCE REALIGNMENT

CHELMSFORD, Mass., June 29, 2007 – Sycamore Networks, Inc. (NASDAQ: SCMR) today announced a workforce realignment that will include a reduction of 46 employees. The realignment, which will be largely completed by the end of July, represents approximately 10 percent of Sycamore’s total workforce. These actions are designed to better align development resources with future growth opportunities, further improve operational efficiencies, and capitalize on additional acquisition synergies. Following completion of this realignment, the Company will employ approximately 415 employees on a worldwide basis.

“These actions are necessary to further strengthen our competitiveness and strategic position, while improving our financial performance,” said Daniel E. Smith, president and chief executive officer.

As a result of these actions, the Company expects to incur restructuring charges and asset impairment charges in the range of $4.0 million to $7.0 million, the majority of which will be recorded in the six-month period ending October 27, 2007. The workforce realignment will be implemented across multiple functional areas. Employees affected by the realignment will receive separation packages, which include severance pay, benefits and outplacement services.

About Sycamore Networks

Sycamore Networks, Inc. (NASDAQ: SCMR) is a leading provider of intelligent networking solutions for fixed line and mobile network operators worldwide. From multiservice access networks to the optical core, Sycamore products enable network operators to lower overall network costs, increase operational efficiencies, and rapidly deploy new revenue-generating services. Sycamore’s global customer base includes Tier 1 service providers, government agencies, and utility companies. For more information, please visit www.sycamorenet.com.

We wish to caution you that certain matters discussed in this news release constitute forward-looking statements regarding future events that involve risks and uncertainties. Readers are cautioned that actual results or events could differ materially from those stated or implied in forward-looking statements. These risks and uncertainties include, but are not limited to, the findings, including possible tax liabilities and penalties resulting from the audit of certain of the Company’s income tax returns by the Internal Revenue Service, risks relating to the formal investigations commenced by the Securities and Exchange Commission and the U.S. Attorney’s office with respect to certain stock options granted by the Company, additional actions and findings that may result from the investigation into such stock options and the accounting therefor, including the restatement of previously issued financial statements, certain purported shareholder derivative actions filed against the Company and certain of its current and former officers and its directors, the Company’s inability to file timely periodic reports on Form 10-K and Form 10-Q with the Securities and Exchange Commission and the possible delisting of the Company’s common stock by NASDAQ. Certain additional risks are set forth in more detail in the section entitled Factors that May Affect Future Results in the Company’s most recent Form 10-K filed by the Company with the Securities and Exchange Commission. The Company disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future results or otherwise.