My point is they can keep any negotiations secret until the stock starts behaving in an irregular manner. Once that happens the TSX will step in and call a halt and ask for the information to be made public.

In order for any negotiations to be currently ongoing they would need to file a report with the TSX and then the TSX will monitor the stock price for unusual activity. If they are trying to keep the negotiations quiet they would have an interest in keeping the stock price stable. Both parties to any deal would have an interest in keeping it stable.