Profits across many of Europe’s largest high-frequency traders slumped by nearly a half last year as they struggled with an industry-wide fall in volumes and regulatory attempts to curb high-speed trading. The figures offer a rare insight into the secretive firms, which use computer-driven techniques to trade securities in fractions of a second. Combined net profits at the European operations of 12 HFT firms – including Citadel Securities, Optiver, Tower Research Capital, Jump Trading and Sun Trading – fell by 46% to £173.5 million during 2012. The figures were based on company accounts from recent months, most of ... (full story)