The top executive of electronic equities market BATS Exchange said Thursday that he would support a ban on so-called flash order types, which are under fire for creating an uneven playing field for traders and investors.

Kansas City, Mo.-based BATS implemented a version of the trading practice in June, citing competitive pressure from rivals, but Chief Executive Joseph Ratterman said he had continued concerns around the issue.

"There are valid reasons to review, debate and even ban flashed orders," Ratterman wrote in a newsletter to clients.

"If a ban would relieve pressure and give our industry the pause necessary to review and reconsider flashed order functionality, then let's collectively go that route," he said.

His comments join criticism of the practice from the heads of NYSE Euronext (NYX) and Nasdaq OMX Group Inc. (NDAQ), who this week called for the flash-type practice to end.

At issue are order types that display stock orders to off-exchange liquidity pools before they are sent out to the broader market to be filled.

The practice was developed a few years ago at the Chicago Stock Exchange and approved by the Securities and Exchange Commission.

Since then, New Jersey-based Direct Edge has developed its own version that has helped it grow into the third-largest U.S. equities platform; BATS and Nasdaq OMX Group begrudgingly followed suit in June, while NYSE Euronext took the issue to the SEC.

The debate centers on whether participants in those off-exchange liquidity pools get an unfair advantage by seeing orders before the rest of the market.

Ratterman argued Thursday that it is disingenuous to suggest that the orders, which are widely published to the full membership of an exchange before they are sent to the private liquidity pool, create illegal front-running opportunities.

He also noted that the practice could provide price improvement for investors, which they might not get if orders were routed to outside exchanges.

-By Jacob Bunge, Dow Jones Newswires; (312) 750 4117; jacob.bunge@dowjones.com