News Summary: Knight Capital soars on buyout offer

News Summary: Troubled Knight Capital jumps after Getco offers to buy it for $3.50 per share

THE BID: Getco, a high-frequency trading firm, has offered to buy Knight Capital Group in a deal that values Knight at $3.50 per share — a 41 percent premium over its closing price on Nov. 23, before the buyout rumors were reported.

KNIGHT STUMBLE: Knight was barely known outside of trading circles until August, when a computer glitch caused it to flood the New York Stock Exchange with erroneous orders. After Knight took responsibility for the disruption, its stock price fell 75 percent in two days.

SUITOR, RESCUER: Getco already owns about 31 percent of Knight's shares because it participated in a $400 million bailout of Knight after the August glitch.