Block Listing

19 May 2006 12:46

Costain Group PLC19 May 2006 Costain Group plc BLOCK LISTING SIX MONTHLY RETURN Name of applicant: COSTAIN GROUP PLC Name of scheme: Costain Group PLC Savings-Related Share Option Scheme Period of return: From: 22 November 2005 To: 19 May 2006 Balance under scheme from previous return: 4,147,605 shares The amount by which the block scheme has been increased, Nilif the scheme has been increased since the date of thelast return: Number of securities issued/allotted under scheme during 3,643,774 sharesperiod: Balance under scheme not yet issued/allotted at end of 503,831 sharesperiod Number and class of securities originally listed and the 4,147,605 ordinary 5p shares (22 November 2005)date of admission Total number of securities in issue at the end of the 357,205,376 ordinary 5p sharesperiod Name of contact: Clive Franks Address of contact: Costain House, Nicholsons Walk, Maidenhead, Berkshire, SL6 1LN Telephone number of contact: 01628 842575 22 May 2006 This information is provided by RNS The company news service from the London Stock Exchange