I suspect each shareholder has a right, and they present that right to the transfer agent and that is the action or trade that is blocked.
I googled the subject and the following are a couple of OSC explanations for their reason to uphold/deny their decision.
http://www.thefreelibrary.com/OSC+Releases+Reasons+In+Neo+Denying+Application+To+Cease+Trade...-a0208284409
http://www.encyclopedia.com/doc/1G1-117154218.html
There are many more, just google if you want. It is quite educational.
Quebec is not bound in any way, so it appears to me that the commission in Quebec, and elsewhare will look to the way in which a SH rights plan was brought for a vote and if it was railroaded through or not to determine if they will quash it or not.