sunnybank, I assume you know that you can claim the tax loss for RXPC without surrendering the shares. Then, if RXPC ever comes back to life and you sell, you'll have to report your gain as if you paid 0 for the stock. It would be a long-term gain, of course, so the tax rate would only be 15%.
I assume you know this and have already claimed the loss. I only ask because it's a tax law that most of us never have to deal with, since very few stocks delist and disappear -- most companies are ethical enough to file BK and let their shareholders sell the shares back to the broker for par value to take the loss.
You have to claim this kind of loss in the year it happened, which means if you haven't claimed the loss yet you have to file an amended 2014 return, which means you'd then have to file an amended 2015 return and 2016 return... a hassle, but if you paid a penny a share for 10 million shares, that's a nice check you'd get back from the IRS.
I tried to explain this to poor DC back in 2014 but he accused me of trying to get him to surrender his shares to his broker so I could then buy them.... even though this is strictly an IRS process and does not involve the broker in any way. SMH.
