Knight Capital in $400 million rescue agreement

Knight Capital (KCG) said that the investors are buying preferred stock convertible to 267 million common shares of the company, according to a document filed with the Securities and Exchange Commission on Monday

But the deal didn't help the high-speed trader's stock, which lost one-third of its value in premarket trading. Last week, Knight lost about 60% of its value over a three-day period last week, despite a robust rally on Friday.