"due to NVIDIA IP ownership issues over the antialiasing code, and that they are not permitted to remove the vendor ID filter."
So it WAS created by Nvidia. The code for AA in that game. They wrote it. Implemented it with Eidos. And through a Vendor ID wanted it to be Nvidia specific. And through much outrage by AMD and co. pressured to remove the Vendor specific ID so that their IP is forcefully surrendered. Because AMD and co. believed they had every right to that IP. Keep going guys, maybe you can get them to give up PhysX as well. After all, AMD surely deserves it, they worked so hard on it and must have spent a fortune.