Case in point about trading stock of a company in bankruptcy.
I made some nice profits trading America West Airlines stock during the time between it filing under Title 11 and the date of stock cancellation. I also made some nice profits from the new stock issued.
Also, for entertainment I track several stocks which have had no business activities for years. I observed one stock that went to over $11 for a company that never had any revenue. Strange? Yes! It happened.