The Financial Services Authority, the UK market regulator that has spent this year striving to build a no-nonsense reputation in its quest to clamp down on insider trading, has picked a high-profile and complex takeover to scrutinise. Its choice of an acquisition involving so many parties may be a statement of intent.

The investigation into the three-way tussle for Clive Cowdery's Resolution Life, a closed life funds administrator, promises to be a stern test of the regulator's ability.