Batterymarch Financial Management, the US fund manager with over $9bn (€7.7) in assets is opening its first office in London by absorbing the assets of its UK-based sister company Legg Mason Investments, a move which is subject to UK regulatory approval.

Legg Mason, whose funds' assets total $170m, will no longer manage money in the UK and its nine fund managers will join Batterymarch, which uses a computer-driven investment process based on database research rather than analyst recommendations.