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News Release

Ray Pellecchia, 212-858-4387
Nancy Condon, 202-728-8379

FINRA Publishes ATS Block-Size Trade Data

WASHINGTON — Beginning today, FINRA is expanding its alternative trading system (ATS) transparency initiative by publishing monthly information on block-size trades occurring on ATSs. The data is available free of charge on FINRA’s website.

Under the initiative to provide additional transparency to over-the-counter (OTC) trading in equity securities, FINRA in June 2014 began publishing on its website volume and trade count information for equity securities executed on an ATS. FINRA began posting the remaining, non-ATS OTC equity volume by member firm and security in April 2016. Starting today, FINRA further adds to this information by publishing monthly ATS block-size trading statistics in all National Market System (NMS) stocks.

“With each additional step, we are providing the investing public and market professionals with greater visibility into ATS trading activity and increasing the transparency of the over-the-counter market,” said Steven A. Joachim, FINRA’s Executive Vice President of Transparency Services. “Greater public understanding of the market helps strengthen investor confidence.”

The statistics for ATS block-size trades are being aggregated across all NMS stocks for a period of one month of trading, and published no earlier than one month following the end of the month for which trading was aggregated. 

Rather than narrowly defining what constitutes a block-size trade, FINRA is using both share-based and dollar-based thresholds, as well as thresholds that include both shares and dollar amount, in the following categories:

  • 10,000 or more shares 
  • $200,000 or more in value 
  • 10,000 or more shares and $200,000 or more in value 
  • 2,000 to 9,999 shares 
  • $100,000 to $199,999 in value 
  • 2,000 to 9,999 shares and $100,000 to $199,999 in value 

For each of those categories, FINRA is publishing monthly trade count and volume information for each ATS aggregated across all NMS stocks. FINRA also is displaying the average trade size and each ATS’s rank as well as “ATS Block Market Share” (the proportion of each ATS’s block-size trading volume in relation to total block-size trading by all ATSs) and “ATS Block Business Share” (the proportion of a particular ATS’s overall trading volume that was done as block-size trades) and rankings of those metrics for each category. 

The data is being published in two new tabs on FINRA’s existing OTC Transparency Data page, marked “ATS Blocks” and “ATS Blocks Download.” With the one-month publication delay, the reports published today reflect ATS trades during August.

FINRA, the Financial Industry Regulatory Authority, is the largest independent regulator for all securities firms doing business in the United States. FINRA is dedicated to investor protection and market integrity through effective and efficient regulation and complementary compliance and technology-based services. FINRA touches virtually every aspect of the securities business – from registering and educating all industry participants to examining securities firms, writing rules, enforcing those rules and the federal securities laws, and informing and educating the investing public. In addition, FINRA provides surveillance and other regulatory services for equities and options markets, as well as trade reporting and other industry utilities. FINRA also administers the largest dispute resolution forum for investors and firms. For more information, please visit