On deck: An all-day SEC roundtable on market volatility, high frequency trading and &#39;dark pools&#39;

When the Securities and Exchange Commission in January announced a broad review of the structure of U.S. stock markets, it wondered aloud whether the rules governing markets ?have kept pace with, among other things, changes in trading technology and practices.?

The ?flash crash? of May 6 showed that the SEC was at least on the right track -- even if the agency, as usual, could be accused of being behind the curve in terms of taking needed action.

On Wednesday the SEC will hold an all-day roundtable session on market structure questions, with the intent of delving into issues that have become a lot more interesting to many investors amid the wild market upheaval of the last month.

The session will be webcast live at www.sec.gov beginning at 6:30 a.m. PDT.

There will be three separate panels. The first one, ?Market Structure Performance and Price Volatility,? will focus on questions including whether the government could take steps to ?appropriately minimize short-term volatility and its harm to longer-term investors,? according to the SEC.

The second panel, ?High Frequency Trading,? will focus on the high-speed computerized trading that has become a hot topic since the May 6 flash crash.

The final panel, ?Undisplayed Liquidity,? will look into issues raised by the volume of stock trading in so-called dark pools, private trading systems where investors can buy or sell without displaying quotations to the public.

Go here for more detailed descriptions of the panels and a list of the scheduled speakers.

Last week, before the SEC released the panel lineups, Sen. Ted Kaufman (D-Del.) criticized the agency based on what he said were preliminary reports about the invited speakers for the high-frequency-trading panel. He said it appeared that the panel would be stacked in favor of trading firms that would be expected to defend the market status quo.

In a follow-up statement on Tuesday, Kaufman said that although the SEC addressed some of his concerns with the panel?s final makeup, he still wasn?t satisfied that the invited speakers represented ?balance.?

-- Tom Petruno