Earlier this week, the Investment Industry Regulatory Organization of Canada (IIROC) published Notice 11-0203 relating to securities trading halts in coordination with the application of "circuit breakers" on U.S. markets.  In the U.S., trading halts occur based on trigger levels of 10%, 20% and 30% drops of the Dow Jones Industrial Average, calculated at the beginning of each quarter using the previous month's average closing value. The NYSE thresholds for the third quarter of 2011 are 1,200 points, 2,400 points and 3,650 points respectively.

It is IIROC's policy that it will coordinate trading halts with U.S. markets, but for days when Canadian markets are open and American markets are closed, IIROC has published related triggers based on drops in the S&P/TSX Composite Index. The TSX trigger levels are: Level 1 (10%) - 1,300 points; Level 2 (20%) - 2,650 points and Level 3 (30%) - 3,950 points, and result in trading halts ranging from 30 minutes to the balance of the trading session, depending on the time of day and magnitude of the market decline. Triggering the Level 1 threshold between 2:00 and 2:30 p.m., for example, would result in a 30 minute halt in trading, while trading would be shut down for the rest of the day should a Level 3 halt occur. The threshold levels for the third quarter are slightly lower than those for the second quarter of 2011.