High-frequency trading (HFT) is capturing headlines, but this concept is nothing new. Everything is relative, and what’s an intraday swing-trading approach today might have been considered the epitome of trading speed in the 1950s. But while perspectives change, one thing has remained constant...

Barclays Plc was so bent on lifting its private trading venue to the upper ranks of Wall Street dark pools that it lied to customers and masked the role of high-frequency traders, according to New York’s attorney general...