By Vicki Needham - 05/20/10 08:20 PM EDT
The 'large trader' tagging rule proposed in April would allow the SEC to gather information such as accounts and affiliates on large trades conducted at fast speeds across different trading venues.
The SEC is expected to vote May 26 on another rule requiring national securities exchanges give regulators data to create a consolidated audit trail that collects and aggregates real-time market data.
Kaufman expressed concern that "rapid advances in technology, combined with market fragmentation, are moving us from an investor's market to a trader's market," saying he couldn't agree more with Schapio's investor-focused strategies.
During today's Senate hearing, Schapiro said the two primary functions of U.S. equity markets are to provide companies a way to raise capital and provide a venue for investors.