SOURCE: Spirent PLC

September 12, 2005 10:26 ET

Spirent PLC announces Holding(s) in Company

Crawley, UK -- (MARKET WIRE) -- September 12, 2005 --

                  NOTIFICATION OF MAJOR INTERESTS IN SHARES

1. Name of listed company

SPIRENT PLC

2. Name of shareholder with a major interest

FIDELITY INTERNATIONAL LIMITED

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 AND ITS DIRECT AND INDIRECT SUBSIDIARIES, BEING NON-BENEFICIAL HOLDERS

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

JP MORGAN BOURNEMOUTH (FPM)                                  6,253,714
NORTHERN TRUST LONDON (FPM)                                  4,312,500
STATE STR BK AND TR CO LNDN (FPM)                            3,448,249
BANK OF NEW YORK BRUSSELS (FPM)                              1,973,300
MELLON BANK (FPM)                                            1,651,600
BANKERS TRUST LONDON (FPM)                                     823,500
HSBC BANK PLC (FPM)                                            447,900
MIDLAND SECURITIES SERVICES (FPM)                              415,500
CLYDESDALE BANK PLC (FPM)                                      130,700
JP MORGAN BOURNEMOUTH (FISL)                                22,453,976
BROWN BROS HARRIMN LTD LUX (FIL)                            23,970,494
BANK OF NEW YORK BRUSSELS (FIL)                                415,700
NORTHERN TRUST LONDON (FIL)                                    105,300
JP MORGAN, BOURNEMOUTH (FII)                                 1,192,800
TOTAL                                                       67,595,233

FPM = Fidelity Pension Management
FISL = Fidelity Investment Services Limited
FIL = Fidelity International Limited
FII = Fidelity Investments International

5. Number of shares / amount of stock acquired

NOT KNOWN

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

NOT KNOWN

7. Number of shares / amount of stock disposed

-

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

-

9. Class of security

ORDINARY SHARES OF 3.3333 PENCE EACH

10. Date of transaction

NOT KNOWN

11. Date company informed

12 SEPTEMBER 2005

12. Total holding following this notification

67,595,233

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)

7.01%

14. Any additional information

SHAREHOLDER PREVIOUSLY REPORTED THAT IT HAD A HOLDING OF 65,868,210 SHARES (6.83%) IN THE COMPANY ON 28 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

12 SEPTEMBER 2005

                      This information is provided by RNS
            The company news service from the London Stock Exchange