Hello, I have a 1099B stock sale that does not have Date Acquired and Cost Basis. The 1099B says "Box 5: Non-Covered Securities - Code X (unknown holding period)". I can get the "date acquired" and the "cost basis" using my own records. Do I just enter the date on box 1b and cost basis on 1e, or do I need to input the "cost basis" as zero, and then input the cost on my records on box 1g (column g on form 8949) as adjustment?
