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 7, 2005
                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    (Commission file number)      (IRS Employer
      of incorporation)                                    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 8.01: Other Events.

On June 7, 2005, the Registrant issued a press release announcing that it will
delay the filing of its quarterly report on Form 10-Q for the three month
period ended April 30, 2005 pending the conclusion of an internal investigation
being conducted under the direction of the Audit Committee of its Board of
Directors. The investigation relates to the accounting of certain stock options
granted during the period from 1999 to 2001, including whether additional stock
compensation expenses should have been recorded during the period under review.
The Registrant also announced that it will file its quarterly report on Form
10-Q for the three month period ended April 30, 2005 as soon as practicable
following the resolution of the internal investigation. The press release
announcing the filing delay and internal investigation is attached as Exhibit
99.1 to this Current Report on Form 8-K and is incorporated by reference
herein.


Item 9.01: Financial Statements and Exhibits.

(c)   Exhibits

Exhibit
Number        Description

99.1          Press Release of the Registrant, dated June 7, 2005.





- -------------------------------------------------------------------------------

                                   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.


/s/ Richard J. Gaynor
- --------------------------------------
Richard J. Gaynor
Chief Financial Officer
(Duly Authorized Officer and Principal
Financial and Accounting Officer)




Dated: June 7, 2005



EXHIBIT INDEX

Exhibit
Number        Description
- -------       -----------

99.1          Press Release of the Registrant, dated June 7, 2005.

EX-99

                                                                   Exhibit 99.1




                                                        [LOGO GRAPHIC OMITTED]
                                                                 SYCAMORE
                                                                NETWORKS

FOR IMMEDIATE RELEASE

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


              SYCAMORE NETWORKS PLANS TO DELAY FILING OF FORM 10-Q
                      FOR THE QUARTER ENDED APRIL 30, 2005

CHELMSFORD, Mass., June 7, 2005 - Sycamore Networks, Inc. (NASDAQ: SCMR) today
announced that it will delay the filing of its quarterly report on Form 10-Q
for the three months ended April 30, 2005 pending the conclusion of an internal
investigation being conducted under the direction of the Audit Committee of its
Board of Directors. The investigation relates to the accounting for certain
stock options granted during the period from 1999 to 2001, including whether
additional stock compensation expenses should have been recorded during the
period under review. While there can be no assurances as to the final results
of the investigation, the Company does not currently anticipate that the
outcome of the investigation will result in any material adjustments being
required to be made to the Company's historical revenues, non-stock option
related expenses or cash positions.

"The Company and its Board of Directors take these matters very seriously and
accordingly we are cooperating fully with the investigation," said Richard
Gaynor, the Sycamore Chief Financial Officer.

The Company reported that it is currently unable to estimate when it will be
able to file its Form 10-Q for the period ended April 30, 2005 but that it
intends to do so as soon as practicable following the completion of the
investigation.

About Sycamore Networks

Sycamore Networks, Inc. (NASDAQ: SCMR) develops and services optical networking
products for telecommunications service providers worldwide. The Company's
products enable service providers to cost-effectively and easily transition
their existing fiber optic network into a network infrastructure that can
provision, manage and deliver economic, high-bandwidth services to their
customers. For more information, please visit www.sycamorenet.com.


Except for the historical information contained herein, we wish to caution you
that certain matters discussed in this news release constitute forward-looking
statements that involve risks and uncertainties. Actual results or events could
differ materially from those stated or implied in forward-looking statements
including the nature and scope of the internal investigation, Sycamore's plans
to delay the filing date of its Form 10-Q for the period ended April 30, 2005
and the timing of its release of its financial results for such period. The
statements contained herein involve risks and uncertainties and actual results
may differ significantly. The risks include, but are not limited to, additional
actions and findings that may result from the continuing Audit Committee
internal investigation. Further, there can be no assurance concerning the
results of the internal investigation, timing of the filing of the Company's
Form 10-Q for the period ended April 30, 2005 or the release of the financial
results for such period. 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.