Holding(s) in Company

Spirent PLC
21 February 2003

          London Stock Exchange

                   NOTIFICATION OF MAJOR INTERESTS IN SHARES


1    Name of company                                             2    Name of shareholder having a major interest



     SPIRENT plc                                                      FMR Corp. and Fidelity International 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 Ltd (FMRCO)          8,717,800
     an individual holder if it is a holding of that person's
     spouse or children under the age of 18                           State Street Nominees Ltd (FMRCO)     428,300

     Companies named in box 2 above and their direct and              State Street Bank & Trust Company (FMRCO)
     indirect subsidiaries, being non-beneficial holders              16,310,700

                                                                      State Street Bank & Trust (FMTC)     3,137,900

                                                                      Chase Manhattan Bank London (FISL)  12,563,179

                                                                      HSBC (FPM)                             619,700

                                                                      Chase Nominees Ltd (FPM)             7,032,896

                                                                      Northern Trust (FPM)                 2,040,200

                                                                      Chase Manhattan Bank London (FIL)    1,111,725

                                                                      Bank of New York Brussels (FIL)        805,100

                                                                      Northern Trust (FIL)                 3,044,100

                                                                      Chase Nominees Ltd (FIL)             9,979,540

                                                                      Bank of New York London (FIL)        5,006,000

                                                                      Nortrust Nominees Ltd (FIL)          3,107,200

                                                                      State Street Bank & Trust (FIL)        296,400

                                                                      HSBC Client Holdings Nominee (UK) Ltd (FIL)
                                                                                                          10,014,400

                                                                      FMRCO - Fidelity Management & Research Company

                                                                      FMTC - Fidelity Management Trust Company

                                                                      FISL - Fidelity Investment Services Ltd

                                                                      FPM - Fidelity Pension Management

                                                                      FIL - Fidelity International Ltd

5    Number of shares 6   Percentage of     7   Number of shares 8    Percentage of Issued
     / amount of          Issued                /amount of stock      Class
     stock acquired       Class                 disposed              
                          
     17,797,468           1.89%                  N/a                   N/a
                          



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

      ORDINARY SHARES OF 3 1/3p EACH                              Not notified                20 February 2003


12    Total holding following this notification             13    Total percentage holding of issued class following
                                                                  this notification

      84,215,140                                                  8.93%
                                                                  


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 Company Secretary, Spirent plc


     Date of notification

     21 February 2003

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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