Knight Capital Struggling to Recover from Trading Glitch

Firm lost $440 million, seeks assistance.

On Wednesday morning, Knight Capital Group Inc. opened trading as a sturdy pillar of Wall Street. By Friday evening, the brokerage firm was clinging to a lifeline, and headed to the weekend in search of a long-term solution.

The firm, which lost $440 million due to a computer-trading glitch, was seeking a financial injection that could help it avoid a sale, breakup or bankruptcy, according to people close to the company.