The SEC has adopted a new rule pursuant to Section 13(h) of the Securities Exchange Act of 1934 requiring large traders to register with the SEC and imposing reporting requirements on their broker-dealers. 

In her speech on July 26, 2011, SEC Chairman Mary L. Shapiro said, “[t]his new rule…would significantly bolster our ability to oversee the U.S. securities markets by allowing the Commission to promptly and efficiently identify significant market participants on a cross-market basis, collect data on their trading activity, reconstruct market events, conduct investigations and, as appropriate, bring enforcement matters.” 

Under the rule, large traders are required to register with the SEC using a new form, Form 13H.  Upon registration, each large trader is issued a unique large trader identification number (LTID).  Large traders are required to provide such LTID to their broker-dealers.  In addition, the rule imposes recordkeeping, reporting and limited monitoring requirements on certain registered broker-dealers through whom large traders execute their transactions. 

A large trader is defined as a person whose transactions in exchange-listed securities equal or exceed 2 million shares or $20 million during any calendar day, or 20 million shares or $200 million during any calendar month.

A full text of the final rule is available here.