Sale of Shares

Costain Group PLC
09 May 2003


                                COSTAIN GROUP PLC

                                 Sale of Shares


Costain Group PLC (the 'Company') announces that it has been notified on 9 May
2003 that one of its major shareholders, Raymond International WLL ('Raymond
International') had sold 10,250,000 ordinary shares in the Company on 6 May
2003. A spokesman for Raymond International has advised the Company that the
sale has been made in order to improve the liquidity in the Company's shares.


Following this notification Raymond International's holding in the Company is
27,493,750 ordinary shares representing 7.96% of the Company's Issued Share
Capital.


                                                                      9 May 2003
                                                                                
ENQUIRIES:

Costain Group PLC                          Tel. [phone]
Clive L Franks  , Company Secretary        Email: [e-mail]


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