Yes, they are able to track original sources (by never putting commingled units in the same bin), per seller help pages (and e.g. Amazon comments in this articl

Yes, they are able to track original sources (by never putting commingled units in the same bin), per seller help pages (and e.g. Amazon comments in this article: https://ftalphaville.ft.com/2019/04/03/1554287401000/Amazon--sub-prime---Part-II/ https://ftalphaville.ft.com/2019/04/03/1554287401000/Amazon-...).