Holding(s) in Company

Spirent PLC
17 December 2002

London Stock Exchange

                   NOTIFICATION OF MAJOR INTERESTS IN SHARES




All relevant boxes should be completed in block capital letters
1    Name of company                                             2    Name of shareholder having a major interest





     SPIRENT plc                                                      FMR Corp (Fidelity Investment Limited)


3    Please state whether notification indicates that it is in   4    Name of the registered holder(s) and, if more
                                                                      than one holder, the number of shares held by
     respect of holding of the shareholder named in 2 above or        each of them

     in respect of a non-beneficial interest or in the case of        Chase Nominees Limited (FMRCO)     7,011,700
     an individual holder if it is a holding of that person's
     spouse or children under the age of 18                           State Street Nominees Limited (FMRCO)
                                                                      679,900
     Company named in box 2 above and its direct and indirect
     subsidiaries, being non-beneficial holders                       State Street Bank & Trust (FMTC)     2,184,900

                                                                      Chase Manhattan Bank London (FISL)
                                                                      12,462,979

                                                                      HSBC (FPM)     452,800

                                                                      Chase Nominees Limited (FPM)     4,032,796

                                                                      Northern Trust (FPM)     1,459,100

                                                                      Chase Manhattan Bank London (FIL)     1,000,348

                                                                      Bank of New York Brussels (FIL)     582,900

                                                                      Northern Trust (FIL)     2,057,500

                                                                      Chase Nominees Limited (FIL)     7,236,840

                                                                      Bank of New York London (FIL)     3,067,800

                                                                      Nortrust Nominees Limited (FIL)     2,259,800

                                                                      State Street Bank & Trust (FIL)     123,900
5    Number of shares 6   Percentage of     7   Number of shares 8    Percentage of Issued
     / amount of          Issued                /amount of stock
     stock acquired                             disposed              Class
                          Class


     10,662,047                                 N/a                   N/a
                          1.13%


9     Class of security                                     10    Date of transaction    11   Date company informed

      ORDINARY SHARES OF 3 1/3p EACH                              Not notified                17 December 2002
12    Total holding following this notification             13    Total percentage holding of issued class following
                                                                  this notification
      45,613,263
                                                                  4.86%




14   Any additional information                            15   Name of contact and telephone number for queries

                                                                LUKE THOMAS - 01293 767658




16   Name and signature of authorised company official

     responsible for making this notification

     LUKE THOMAS, DEPUTY SECRETARY, SPIRENT PLC



     Date of notification

                                                                17 December 2002

London Stock Exchange, Company Announcements Office, Old Broad Street, London
EC2N 1HP

Facsimile: 0207 588 6057, 0207 334 8964/8965/8966 (PLEASE DO NOT POST)

Enquries: Continuing Obligations: Telephone: [phone]


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