Fidelity, Royce funds biggest losers in Knight Trading debacle

The top five holders of Knight Capital Group Inc. have lost more than $265 million combined since trading opened Wednesday, when a trading algorithm in the firm's market-making unit reportedly malfunctioned and wreaked havoc on orders placed for more than 150 stocks. According to 13F filings, Fidelity funds were the largest holders of the stock, with more than 15% as of March 31, followed by Legg Mason affiliate Royce & Associates, with 10.9%. The company announced Thursday it is exploring its options to "strengthen its capital base."