In this case, I don't think it is as straightforward as normal. There was also a "contingent" payout from Shire on Jan 22 ($~86.18 / share) in addition to the Takeda stock received on Jan 10. So in this "taxable merger", I received $~95.77 in Takeda stock plus $86.18 in cash. My basis which goes back to Baxter was $~85.00 / share. So once you take into account the $86.18 in cash received, the Takeda stock was 100% gain, i.e. zero basis.
Schwab is showing two entries on the 1099-B, one for the Takeda stock received with $zero basis. The second entry shows the additional gain created by the contingent payout. I don't really like how they are showing it on the 1099, especially the way they are showing the cash proceeds portion but in total the gain is correct.
