In the statutes there's no limit to the financial investments that a foreigner can have in a Canadian company. There are control issues that are raised in the statute, though, and they are twofold. The first one is voting shares and the second one is control in fact. So you're right in saying that there is no limit on the amount of money a foreigner can invest in Canada.
On March 25th, 2010. See this statement in context.