Director Shareholding

Spirent PLC
4 April 2001





London Stock Exchange
Company Announcements Office
Old Broad Street
London
EC2N 1HP

(020 7588 6057)

                                                                  4 April 2001

Dear Sirs

Spirent plc - NOTIFICATION OF DEEMED INTERESTS BY DIRECTORS

Spirent QUEST Limited, the trustee and registered shareholder for the Spirent
Employee Benefit Trust, has today disposed of the following Ordinary shares in
Spirent to satisfy the exercise of options under the Company's SAYE Share
Option Scheme:

           No of Shares                                        Option Price (£)
                  1,670 @                                                1.1668
                  1,670



Following this disposal the total number of shares held by the Trust is
4,719,745 shares (representing 0.509 % of the issued share capital).

Nicholas Brookes and Eric Hutchinson, both Directors, are potential
beneficiaries of the Trust (together with all other employee share option
holders) and are therefore treated under the Companies Act 1985 as having a
deemed interest in the total number of shares held by the Trust. As a result,
the Directors' deemed interests in the Trust have been reduced by the above
number of shares disposed of.

For the avoidance of doubt, the Company confirms that this notification does
not relate to an actual dealing in securities by the said Directors whose
beneficial interests in the Company remain unchanged notwithstanding the above
events.

If you have any queries, please do not hesitate to contact the writer (Tel
01293 767676).

Yours faithfully,



Michael Arnaouti

Company Secretary