Transaction in Own Shares

Spirent Communications plc: Transaction in own shares

16 December 2010

Spirent Communications plc (the "Company") announces that it has today purchased through UBS Limited 3,000,000 Ordinary Shares at an average price of 152.1002 pence per share. The highest price and the lowest price paid for these shares were 152.3 pence and 152.1 pence respectively.

These shares will be cancelled.

Following the purchase and cancellation of these shares the Company has 674,929,721 Ordinary Shares in issue. The Company holds no Ordinary Shares in Treasury. This figure (674,929,721) represents the total voting rights in the Company and may be used by shareholders as the denominator for the calculations by which they can determine if they are required to notify their interest in, or a change to their interest in, the Company under the Financial Services Authority's Disclosure and Transparency Rules. Any such notifications should be sent by fax to +44 1293 767990 or by email to [email protected] marked for the attention of the Company Secretary.