Costain Group Regulatory News (COST)

Costain Group PLC ('Costain')

LEI: 213800PKIJBZ2EDTKC88

18 May 2026

External Appointment

Further to the announcement by Harworth Group plc ('Harworth') released earlier today and in accordance with UK Listing Rule 6.4.9R(2), Costain announces that Tony Quinlan, Non-Executive Director, will be appointed as Independent Non-Executive Director of Harworth with effect from 1 June 2026. On appointment Mr Quinlan will join Harworth's Audit and Remuneration Committees.

Tony is Senior Independent Director, Chair of the Costain Audit and Risk Committee and a member of all Costain Board Committees.

Costain improves people's lives by creating connected, sustainable infrastructure that enables people and the planet to thrive. Through the delivery of predictable, best-in-class solutions across the transport, water, energy and defence markets, we are creating a sustainable future and securing a more prosperous, resilient and decarbonised UK.