Holding(s) in Company

Spirent Communications PLC
22 May 2007


TR-1: NOTIFICATION OF MAJOR INTERESTS IN SHARES 

1. Identity of the issuer or the underlying issuer of existing       Spirent Communications plc
shares to which voting rights are attached:

2. Reason for the notification     (please tick the appropriate box or boxes)

An acquisition or disposal of voting rights - DISPOSAL                          X

An acquisition or disposal of financial instruments which may result 
in the acquisition of shares already issued to which voting rights are
attached

An event changing the breakdown of voting rights

Other (please specify)

3. Full name of person(s) subject to the        (i) Lexa BV
notification obligation:
                                                (ii) Goran Ennerfelt (a non-executive director of
                                                Spirent Communications plc) has a connected interest
                                                in the shareholding of Lexa BV. This is due to the
                                                fact that he is President and Chief Executive Officer
                                                of Axel Johnson AB, a member of the Axel Johnson Group
                                                which owns Lexa BV.

4. Full name of shareholder(s) (if different                              -
from 3.):

5. Date of the transaction (and date on which the threshold is               22 May 2007
crossed or reached if different):

6. Date on which issuer notified:                                            22 May 2007

7. Threshold(s) that is/are crossed or reached:                              Below 10 %

8. Notified details:                                             Sold 40,400,000 Ordinary shares


A: Voting rights attached to shares
Class/type of     Situation previous to    Resulting situation after the triggering transaction
shares            the Triggering
                  transaction
 if possible      Number of    Number of   Number of     Number of voting rights ix  % of voting rights
using the ISIN    Shares       Voting      shares
CODE                           Rights viii Direct        Direct  x   Indirect xi     Direct     Indirect

Ordinary shares   90,400,000   90,400,000   50,000,000   50,000,000        N/A          5.67       N/A

ISIN:
GB0004726096



B: Financial Instruments
Resulting situation after the triggering transaction
Type of financial    Expiration date Exercise/ Conversion      Number of voting rights    % of voting
instrument                           Period/ Date              that may be acquired if    rights
                                                               the instrument is
                                                               exercised/ converted.

        N/A                N/A                  N/A                       N/A                   N/A


Total (A+B)
Number of voting rights                            % of voting rights
                    
50,000,000                                         5.67%


9. Chain of controlled undertakings through which the voting rights and/or the financial instruments are effectively
held, if applicable :

(i) Lexa BV

(ii) Goran Ennerfelt (a non-executive director of Spirent Communications plc) has a connected interest in the
shareholding of Lexa BV. This is due to the fact that he is President and Chief Executive Officer of Axel Johnson AB, a
member of the Axel Johnson Group which owns Lexa BV.



Proxy Voting:

10. Name of the proxy holder:                                                  N/A

11. Number of voting rights proxy holder will cease to hold:                   N/A

12. Date on which proxy holder will cease to hold voting                       N/A
rights:

13. Additional information:                                          N/A



14. Contact name:                          Arie Bouman - Managing Director, LEXA BV

15. Contact telephone number:              [phone]

C:        Additional information

Contact at Issuer: Michael Anscombe, Deputy Company Secretary, Spirent Communications plc

Telephone: [phone]






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