This reaction is telling.

TORONTO - Toronto Stock Exchange and TSX Venture Exchange will not resume trading Wednesday due to continuing technical issues with its data feeds.

Trading in stocks on both Toronto's main and venture exchanges was halted moments after the markets opened on Wednesday due to a technical problem in what traders are calling the worst disruption in memory.

The TMX Group was offering little explanation by mid-afternoon aside from saying the crash was not related to its recently introduced Quantum trading engine.

There was no trading on the Toronto Stock Exchange due to a technical glitch at the start of the day.

Reuters

In a brief statement, the parent company of the Toronto Sock Exchange and TSX Venture Exchange said it was halting trading "due to technical issues with data feeds," which "provide information to investors to guide their trading decisions."

Trading was stopped at 9:48 a.m. local time after both exchange's data feeding system crashed, Luc Bertrand, chief executive of TMX Group, said in a television interview.

Data did manage to make its way to some clients but not others, Bertrand said in an interview on Business News Network. Trading was halting immediately after the irregularity was recognized to ensure "all participants are treated the same way," he said.

TMX had no explanation as to the exact cause of the glitch.

"We will resume the market the minute we have a solution in place," Bertrand said, without giving any timetable.

"This is the worst interruption that I have ever seen," said John Aiken, an analyst at Dundee Securities Corp. "Reputationally, this definitely gives a boost to everybody but TMX Group."

Some institutional traders have migrated to alternative trading systems such as Toronto-based platforms Pure Trading and Alpha, but "nowhere near what you would expect," said Ian Bandeen, the chief executive of Pure.

Bandeen said Pure had seen about 12.5 million shares trade hands by noon, about double what's normal.

"Our activity has definitely gone up on both Pure and Alpha today, that's for sure," said Ray Tucker, managing director of institutional equities at TD Newcrest.

The TSX average daily trading volume in recent months has been about 450 million shares.

"These developments don't benefit anybody," Bandeen added. "It's to everyone's benefit to have a fully functioning market."

Some trading was diverted to the U.S.

"It's incredibly frustrating because we've got clients who have given us orders and we can't trade the stocks, and we're forced to send business or whatever names are inter-listed down to the States," said Bruce Latimer, a trader at Dundee Securities. "So we're taking money out of the Canadian market and trading on the U.S. market."

The crash is certainly not the first technical glitch involving communication irregularities between traders and the exchange. On May 22, a 45-minute interruption in the morning involving 38 stocks resulted when inaccurate orders were received through the then six-month old Quantum trading platform.

With files from Reuters