According to the IRS PTSC is not worthless as long as there is a market that trades it. To claim a Capital Gains loss which I have several lifetimes of carry over, you need to actually sell the stock at a loss unless there is some IRS defined way to claim the stock as "worthless". In other words if you want to claim a loss you will need to sell the stock for less than you purchased it. Bankruptcy is one condition that can qualify PTSC as worthless but ... SO, anybody out there want to buy my tax loss. It's a whopper!!!