McColl, 65, is chief executive and chairman of the East Kilbride-based Clyde Blowers engineering group. In 2014 it took control of the Ferguson shipyard, which had slid into administration despite having orders for two ferries. After taking the company private and increasing his holding in 2001, he embarked on a series of acquisitions. Clyde Blowers Capital made £120m profit on £1.75bn turnover in 2014 and is worth at least £1.7bn. That values McColl's stake at £1.02bn. There are other assets.