Holding(s) in Company

Spirent PLC
02 August 2005

                   NOTIFICATION OF MAJOR INTERESTS IN SHARES



1. Name of listed company

SPIRENT PLC



2. Name of shareholder with a major interest

VIDACOS NOMINEES



3. Please state whether notification indicates that regarding the holding of the
shareholder named in 2 above; in respect of a non-beneficial interest; or in the
case of an individual holder if it is a holding of that person's spouse or
children under the age of 18

SHAREHOLDER IN 2 ABOVE



4. Name of the registered holder(s) and, if more than one holder, the number of
shares held by each of them

SHAREHOLDER IN 2 ABOVE



5. Number of shares / amount of stock acquired

-



6. Percentage of issued class (any treasury shares held by the listed company
should not be taken into account when calculating percentage)

-



7. Number of shares / amount of stock disposed

UNKNOWN



8. Percentage of issued class (any treasury shares held by the listed company
should not be taken into account when calculating percentage)

UNKNOWN



9. Class of security

ORDINARY SHARES OF 3.3333 PENCE EACH



10. Date of transaction

NOT NOTIFIED



11. Date company informed

02 AUGUST 2005



12. Total holding following this notification

37,052,198



13. Total percentage holding of issued class following this notification (any
treasury shares held by the listed company should not be taken into account when
calculating percentage)

3.84%


14. Any additional information

SHAREHOLDER PREVIOUSLY REPORTED THAT IT HAD A HOLDING OF 39,137,860 SHARES 
(4.06%) IN THE COMPANY ON 01 JUNE 2005.



15. Name of contact and telephone number for queries

LUKE THOMAS - 01293 767658


16. Name and signature of duly authorised company official of the listed company
responsible for making this notification

LUKE THOMAS - DEPUTY COMPANY SECRETARY


Date of notification

02 AUGUST 2005



                      This information is provided by RNS
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