Tech entrepreneur Paddy Cosgrave had a close relationship with telecoms mogul Denis O’Brien and flew several times on his private jet to places like Davos and the US until the businessman stopped sponsoring the Web Summit, according to new claims made by his former business partner Daire Hickey. The Web Summit chief executive viewed O’Brien, whose company Digicel gave in excess of around €200,000 to the conference in sponsorship in the early years, as a mentor and regularly cited his advice on how to manage negotiations and deal with the press, it is claimed. However Cosgrave subsequently waged a “campaign…