It was a jointly owned patent. Later on, Cargill was making the case that their development agreement with BioAmber on the jointly own patents said that they'd have sole ownership if one of them went under. One of them did, but Cargill didn't act until the court had approved the APA and the sale was closed.
It isn't unusual for a dead name to continue to be listed on patents and other documents. It is up to the new owner to get it changed.