Spire Europe, a little-known but expanding European high-frequency trading firm, posted its highest trading profits on record in 2014 – a year in which it increased headcount by 60%, new filings show.

Spire - owned by US trading firm Tower Research Capital - posted revenues of £96.4 million in 2014, up from £59.9 million in the prior year, according to a Companies House filing on October 6. Its pre-tax profits increased to £19.1 million from £3.8 million, the majority of which, around 75%, was generated in Europe, not including the UK