The London Stock Exchange Group is much less about London, stocks, or even exchanges these days. The most appropriate part of its moniker now seems to be the word “group”.

A powerful symbol of this transformation was last week's announcement of a $2.7 billion deal to acquire Frank Russell, the Seattle-based stock index and asset manager. The deal will transform the LSE, already the owner of the FTSE group, into an index giant to rival MSCI and S&P Dow Jones.