Sure Pinks can be shorted, tough to do in Canada, I've yet to find a broker that will do it, in fact it's tough in Canada to find any broker that will let you short anything under a buck, any venue.
Margins though are much lower in Canada than the US where for stocks under $2.50 it's going to cost you $2.50/share margin and maintenance fees.
Canada it's for stocks under .50 it's 100% margin plus .50/share, stocks over .50 it's a flat 200% margin, or was last I checked.
Doesn't make much sense to tie up literally millions of $$ to make a few thousand.
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