The Investment Industry Regulatory Organization of Canada (IIROC) today announced the implementation of single-stock circuit breakers to facilitate a halt across all marketplaces in the trading of a security experiencing rapid price movement. The circuit breaker program is intended to address short term, unexplained price volatility in individual securities.

Specifically, securities that are part of the S&P/TSX Composite Index, as well as ETFs comprised principally of listed securities, will be subject to trading halts in the event of a price increase or decline of at least 10% in a five minute period. The circuit breaker will initially halt the particular security for five minutes, and this time may be extended for a further five minute period if a significant imbalance of buy and sell orders remain. Circuit breakers will not be active in the first 20 minutes following the regular market opening nor in the 30 minutes prior to the regular close of trading.

Should IIROC determine that a further halt is required such as, for example, to allow for the dissemination of material news, IIROC may replace the single-stock circuit breaker halt with a traditional "regulatory halt". Any trades executed after the triggering of the circuit breaker but prior to the halt at more than 5% beyond the trigger price would be cancelled.

Single-stock circuit breakers will be implemented as part of an implementation phase expected to last between six months and a year, during which time IIROC intends to monitor trading in all securities on Canadian marketplaces. Following the initial implementation phase, IIROC intends to review the single-stock circuit breaker program and publish the results of its review, at which point it will solicit comment on whether adjustments should be made to the terms of the program.

IIROC today also released thepublic comments received in response to its initial proposals, released in November 2010, as well as its responses. The circuit breaker program announced today will ultimately be more limited than IIROC's initial proposal, which would have applied to all securities listed on a Canadian exchange. For more information, see IIROC Notices 12-0040 and 12-0041.

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