grant_yb2_yyyymmdd.tar: This is the main grant file.
Contains the images of each patent grant issued weekly (Tuesdays) from
January 5, 2010 to present in Tagged Image File Format (TIFF) Revision
6.0 with CCITT Group 4 Compression (single-page TIFFs) from the USPTO
Patent Grant Image/TIFF (aka Yellow Book) product.
grant_yb2_yyyymmdd_rx.tar: A "new" separate file for Reexaminations.