This happens almost every time there is big news, and the Canada market gets halted and the OTC market doesn't. We've seen this on Boxing Day before.
The OTC side continues to trade with limited inventory and it's easy to run the price up.
When the Canadian market resumes trading the OTC price has to reconcile back to the Canadian market price, be it higher or lower, because the Canadian market represents ~85% of the trading volume and inventory.
The OTC mostly just matching the price of the larger Can market.
It doesn't happen every time, but more often than not it does.
Apparently today the Canadian side wasn't as thrilled with the merger news as the US side was.
it's a nasty arbitrage play.
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