I was looking through one of my accounts the other day, seeing what can get cleaned out for EOY tax purposes and ran into the CVIA dividend AHCD shares. They were right next to my CVIAP. As a dividend with no basis, I don't think they can be written off, so I'd say leave them where they are.
NO BASIS means you didn't pay for them so you havn't lost anything. There may be an outside chance the CVIAP will convert, however, I doubt AHCD will ever trade.