UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 6-K
REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16
UNDER THE SECURITIES EXCHANGE ACT OF 1934
For the month of August, 2006
SPIRENT COMMUNICATIONS plc
_____________________________________________________________________
(Translation of registrant's name into English)
Spirent House, Crawley Business Quarter, Fleming Way, Crawley, West Sussex
RH10 9QL, UK.
_____________________________________________________________________
(Address of principal executive offices)
Indicate by check mark whether the registrant files or will file annual reports
under cover Form 20-F or Form 40-F.
Form 20-F X Form 40-F.....
Indicate by check mark whether the registrant by furnishing the information
contained in this Form is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.
Yes ..... No X
If "Yes" is marked, indicate below the file number assigned to the registrant
in connection with Rule 12g3-2(b): 82- ________
NOTIFICATION OF MAJOR INTERESTS IN SHARES
1. Name of listed company
SPIRENT COMMUNICATIONS PLC
2. Name of shareholder with a major interest
LEXA B.V.
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
IN RESPECT OF THE BENEFICIAL HOLDING OF LEXA B.V.
4. Name of the registered holder(s) and, if more than one holder, the number of
shares held by each of them
LEXA B.V.
5. Number of shares / amount of stock acquired
N/A
6. Percentage of issued class (any treasury shares held by the listed company
should not be taken into account when calculating percentage)
N/A
7. Number of shares / amount of stock disposed
N/A
8. Percentage of issued class (any treasury shares held by the listed company
should not be taken into account when calculating percentage)
N/A
9. Class of security
ORDINARY SHARES OF 3 & 1/3 PENCE EACH
10. Date of transaction
30 AUGUST 2006 (SEE ADDITIONAL INFORMATION)
11. Date company informed
30 AUGUST 2006
12. Total holding following this notification
120,000,000 ORDINARY SHARES
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)
13.03%
14. Any additional information
SPIRENT COMMUNICATION PLC IS CURRENTLY OPERATING A SHARE BUY BACK PROGRAMME AND
AS AT 30 AUGUST 2006 HAD PURCHASED 50,990,000 SPIRENT COMMUNICATIONS PLC
ORDINARY SHARES OF 3&1/3 PENCE INTO TREASURY OUT OF A TOTAL ISSUED SHARE CAPITAL
OF 971,934,304 SHARES. AS SHARES HELD IN TREASURY ARE NOT INCLUDED IN THE
CALCULATION OF HOLDINGS OF MAJOR SHAREHOLDERS A CONSEQUENCE OF THE BUY-BACK
PROGRAMME HAS BEEN THAT THE PERCENTAGE HOLDING OF LEXA B.V. HAS INCREASED FROM
12.4% OF THE ISSUED SHARE CAPITAL TO 13.03% OF THE ISSUED SHARE CAPITAL,
ALTHOUGH THE ACTUAL NUMBER OF SHARES HELD OF 120,000,000 REMAINS UNCHANGED.
15. Name of contact and telephone number for queries
WARREN NASH - 01293 767676
16. Name and signature of duly authorised company official of the listed company
responsible for making this notification
WARREN NASH
Date of notification
31 AUGUST 2006
Signatures
Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.
______MICHAEL ANSCOMBE______
(Registrant)
Date __ 31 August 2006 By ____/s/ Michael Anscombe____
(Signature)*