Dark pools' impact on markets
Maureen O'Hara, the Robert W. Purcell
Professor of Management and professor
of finance, shared her expertise in market
microstructure in an analysis of recent
research on "dark pools," by Phys.Org (Feb.
3). Dark pools are privately run stock markets
that do not show participants' orders to the
public before trades happen, the site reports, and now represent at least one-eighth, and possibly more, of all stock
trading volume in the U.S. Recent academic research suggests that
"dark pools can improve market performance and not degrade it as
has been suggested by some," O'Hara said.
The Wall Street Journal (Dec. 9) sought out O'Hara to shed light on a rule change that requires disclosure of odd-lot trades — those for fewer than 100 shares. "These are not innocuous, little trades anymore," she said. "They are part of larger trading strategies that may indeed have information value. Until now, only those who could afford proprietary data feeds had this information."