I have a 1099-B for sales of stock I earlier withdrew out of a 401K (using the total distribution/NUA option). Although the form doesn't have the cost basis, I know the exact basis from the 401K distribution. I'm getting an advisory on Turbo Tax that I need to mail a form 8453 along with "statements".
The form 8453 has a series of check boxes and none seem to apply to my situation, and it says not to send it if you can't check one of the boxes. Second, I have no idea what "statements" they want to see. I only have a 1099-R from my 401(k) withdrawal and my 1099-B for the sale. Any idea what they want and/or what might happen if I don't mail it in? Thanks!