Sale of Shares

Costain Group PLC
09 September 2004

Costain Group PLC (the 'Company')

Sale of Shares


Costain Group PLC announces that it has been notified on 6 September 2004 that
one of its shareholders, Raymond International WLL ('Raymond International') has
recently sold in a number of separate tranches 2,750,000 ordinary shares in the
Company.

Following this notification Raymond International's holding in the Company is
15,512,500 ordinary shares representing 4.39% of the Company's issued share
capital.

                                                                9 September 2004

Enquiries:
Costain Group PLC -
Clive L Franks, Company Secretary     01628 842 575     [e-mail]


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