Man Vs. Machine: Seven Major Players in High-Frequency Trading

High-frequency trading has grabbed headlines in the past year, but little is known about the top players in the business. These speed-focused hotshots aren't household names such as George Soros or Warren Buffett. That's partly because of the the secretive nature of the industry, which has largely shunned the limelight, at least until recently. Here's seven forces in the business. 

via Man Vs. Machine: Seven Major Players in High-Frequency Trading - CNBC