IBM made big news yesterday. First, and as expected, IBM was named by the PTO as the company obtaining the greatest number of patents for the year 2004. IBM was awarded over 3,000 patents last year!
Then, IBM pledged [press release] to allow open access to key inventions covered by 500 of IBM's software patents. This pledge will likely be seen as legally binding commitment by IBM to not assert the 500 named patents against any manufacture/user of open source software (OSS). The 500 patents are categorized and listed in a 20 page pdf document.
(1) It would be my guess that, although IBM's patent portfolio has the greatest number of patents, it is not the most valuable. A straight patent count is not worth much.
(2) These 500 patents are only a drop in the bucket for IBM. They received 3000+ patents this year, and have been the #1 patentee for the past 11 years. They have well over 30,000 valid patents. And FYI, IBM can still sue you if your software is not opensource.