I'm using TaxAct this year, and after importing all of my LC and Prosper 1099-B transactions, TaxAct is flagging a warning regarding each of the transactions with a $0 "proceeds" (which is the case for all the charge-off's that have had no recoveries so far):
I don't think the IRS really cares about the dates as long as the amounts match what LC sent them. You may be able to go to the form view and manually change the dates if you desire.
That said, I just enter the total sale price and cost basis and say the dates are various instead of listing each and every note. Otherwise, my tax filing would be as big as a book.
the IRS tax code book, correct?
I did it with TaxAct the way Storm says. The cost basis of charged offs (Dec. 31, '17) and sales were added together, and all were counted as short term, on line 1a, Sched. D. Line 8a (long term) stayed blank except for the prior carryover on Line 14 and 15. The warning said that was happening, but I couldn't find anything to do about it so I gave up and filed anyway.