content: <PAGE>
  
                                  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:  September 7, 2001
  
  
                               REDBACK NETWORKS INC.
          --------------------------------------------------------------
              (Exact Name of Registrant as Specified in its Charter)
  
  
           Delaware                      000-25853               77-0438443
  ----------------------------    ------------------------     ----------------
  (State or Other Jurisdiction    (Commission File Number)     (I.R.S. Employer
      of Incorporation)                                     Identification Number)
  
  
                                  250 Holger Way
                                San Jose, CA  95134
                                   (408) 571-5000
   ------------------------------------------------------------------------------
   (Addresses, including zip code, and telephone numbers, including area code, of
                            principal executive offices)
  
  ITEM 5. OTHER EVENTS.
  
     A copy of a portion of the Registrant's press release dated September 7,
  2001, relating to Redback's announcement that it had completed its acquisition
  of Merlin Systems, Inc.
  
     The press release filed as an exhibit to this report includes "safe harbor"
  language pursuant to the Private Securities Litigation Reform Act of 1995, as
  amended, indicating that certain statements about the Company's business
  contained in the press release are "forward-looking" rather than "historic." The
  press release also states that these and other risks relating to Redback's
  business are set forth in the documents filed by Redback with the Securities and
  Exchange Commission, specifically the most recent report on Form 10-Q, and the
  other reports filed from time to time with the Securities and Exchange
  Commission.
  <PAGE>
  
  ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.
  
      (c)  EXHIBITS.
  
          99.1  Press Release dated September 7, 2001
  <PAGE>
  
                                     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 hereunto duly authorized.
  
  
                                        REDBACK NETWORKS INC.
  
  
  DATE:  September 12, 2001             By: /s/ Dennis P. Wolf
                                           --------------------------
                                           Dennis P. Wolf
                                           Senior Vice President of Finance and
                                           Administration, Chief Financial Officer
                                           and Corporate Secretary
metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "d8k.txt", "description": "FORM 8-K", "secsgml_size_bytes": 3006}]
metadata_filer: {"company-data": {"conformed-name": "REDBACK NETWORKS INC", "cik": "0001081290", "assigned-sic": "7389", "irs-number": "770438443", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-25853", "film-number": "1735677"}, "business-address": {"street1": "250 HOLGER WAY", "city": "SAN JOSE", "state": "CA", "zip": "95134*1306", "phone": "4085715000"}, "mail-address": {"street1": "1195 BORREGAS AVE", "city": "SUNNYVALE", "state": "CA", "zip": "94089"}}
text: 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:  September 7, 2001
  
                               REDBACK NETWORKS INC.
          --------------------------------------------------------------
              (Exact Name of Registrant as Specified in its Charter)
  
           Delaware                      000-25853               77-0438443
  ----------------------------    ------------------------     ----------------
  (State or Other Jurisdiction    (Commission File Number)     (I.R.S. Employer
      of Incorporation)                                     Identification Number)
  
                                  250 Holger Way
                                San Jose, CA  95134
                                   (408) 571-5000
   ------------------------------------------------------------------------------
   (Addresses, including zip code, and telephone numbers, including area code, of
                            principal executive offices)
  
  ITEM 5. OTHER EVENTS.
  
     A copy of a portion of the Registrant's press release dated September 7,
  2001, relating to Redback's announcement that it had completed its acquisition
  of Merlin Systems, Inc.
  
     The press release filed as an exhibit to this report includes "safe harbor"
  language pursuant to the Private Securities Litigation Reform Act of 1995, as
  amended, indicating that certain statements about the Company's business
  contained in the press release are "forward-looking" rather than "historic." The
  press release also states that these and other risks relating to Redback's
  business are set forth in the documents filed by Redback with the Securities and
  Exchange Commission, specifically the most recent report on Form 10-Q, and the
  other reports filed from time to time with the Securities and Exchange
  Commission.
  ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.
  
      (c)  EXHIBITS.
  
          99.1  Press Release dated September 7, 2001
  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 hereunto duly authorized.
  
                                        REDBACK NETWORKS INC.
  
  DATE:  September 12, 2001             By: /s/ Dennis P. Wolf
                                           --------------------------
                                           Dennis P. Wolf
                                           Senior Vice President of Finance and
                                           Administration, Chief Financial Officer
                                           and Corporate Secretary