@fanfare
Thanks for the follow up.
In the date acquired box (Box 1b) on the 1099-B it has the date of my father's death, which is the date used for stepping up the cost basis. So normally it would seem I should just copy what's in Box 1b on the 1099-B to column 1b on form 8949. (But that looks a little weird, since the date the shares were sold were only a month later, even though the 1099-B says correctly they are long term shares.)
But if technically in this situation my mother inherited the shares from my father (even though they are held in a trust account for which they were both beneficiaries and now my mother is the sole surviving beneficiary), and this technical inheritance allowed for the cost basis step up on my father's date of death, or if technically the shares are inherited because my father inherited them from his father, then perhaps I am supposed to put "inherited" in column 1b on form 8949.
So either I'd put my father's date of death on form 8949 for date acquired (as stated in Box 1b the 1099-B) or I'd put "inherited."
