From my experience it's quite rare, however, I don't generally follow Grey Market tickers very closely either. If I have one that gets suspended (I've had 3 this year alone) then I usually dump it or write it off as a 'worthless security'. I'm not going to hang around the message board to bash and/or complain as I have better things to do with my time, and a ton of other tickers on my watchlist to research.
EPTI is one of the few that I will continue to hold and follow, as I am very interested in seeing the outcome, if anything out of curiosity sake. IMO if a company like EPT is ultimately unable to resume trading on the Pink or OTCQB then it's prob unlikely that anyone will ever be able to again after suspension.
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