The USPTO has adopted PDF as the default format for displaying patent documents from its databases, making it one of the last (if not last) of the major patent offices to switch to the world's most popular document image format. Since 1998, viewing US patent documents obtained from the USPTO website required the use of a TIFF plugin such as alternaTIFF or interneTIFF.
I'm the librarian for research services in the Engineering and Science Library at Queen's University in Kingston, Ontario. I've been working with patent information since 1991, including seven years at the U.S. Patent and Trademark Office. I believe that the dissemination of patent information is a public good and should be promoted, especially in the education of science and engineering students.