Tax question, not until there is an event to close the trade
If you hold onto the warrants, which was what the old common was converted into, you can not claim the loss until there is an 'event' to complete the trade.
In order to be able to claim the loss, you would need to sell the warrants and then that would close the trade and give you an event to claim the loss against. In cases where the security does not trade any more, like these warrants, you can usually ask your broker to take them from you, and then that will give you an event so you can claim the loss. (The warrants will then be owned by the brokerage firm and someday, maybe, they can sell them to someone or wait for them to expire years from now.)
If you hold onto the warrants, then you will not be able to claim the loss on the trade until the warrants expire.
Louis J. Desy Jr.
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