The investors who bailed out Knight Capital Group Inc. by purchasing $400 million in convertible securities are gaining control of the biggest trading partner for individuals in the world’s largest stock market.

While last week’s $440 million trading loss highlighted Knight’s importance to institutional traders, the company accounted for 29 percent of the average monthly volume in U.S. equity trading by individuals in the first quarter, according to a June 7 presentation. Stifel Nicolaus & Co. and TD Ameritrade Holding Corp., two of the firm’s rescuers, sent 38% and 9% of market orders in New York Stock Exchange-listed securities to Knight last quarter, respectively, according to public execution-disclosure statements.

Subscribe Now

Access to premium content including in-depth coverage of mutual funds, hedge funds, 401(K)s, 529 plans, and more.

3-Week Free Trial

Insight and analysis into the management, marketing, operations and technology of the asset management industry.