Client received (2) K-1s after the personal returns were already filed. These K-1s are under a new entity that has not been reported ever on the returns. The only items reported are in box 13, other deductions. A note on the K-1 says that the basis is unknown and it would be based on the tax basis of the member in their bankruptcy claim. The amounts in box 13 are rather small and would not give much of a deduction, if any. if the returns do not get amended, would the IRS send the client a notice? What do others do in this situation? Client must have some basis because she lost money in the bankruptcy.