According to this article in USA Today, Toyota received a hefty 1,491 U.S. patents in 2012, the most of any automaker and an increase of 30% from the previous year. The number of patents granted was reported by the Intellectual Property Owners Association.
The U.S. Patent and Trademark Office puts out its own report of Patenting by Organizations each year. The USPTO report indicates that TOYOTA JIDOSHA K.K. was 18th on the list of all patentees in 2012, at 1,173 patents granted (the discrepancy is probably due to some patents being assigned to Toyota’s subsidiaries, which would not be counted by the USPTO).
Idaho’s MICRON TECHNOLOGY, INC. was 32nd on the list, receiving 913 patents last year.