Investment funds managed by Madison Dearborn Partners LLC and HPS Investment Partners LLC are increasing their respective stakes in The Ardonagh Group Ltd.

The funds agreed to acquire Ardonagh TopCo shares and Sentry B shares at £1.175 apiece from certain existing institutional investors and other minority shareholders, implying a total equity valuation of approximately £860 million for the group.

Following the deal, which is set to close June 7, MDP funds' Ardonagh shareholding will increase to 43% from 33%, while HPS funds' shareholding will increase to 54% from 52%.