Patent lawyers may be surprised to know that while today, most companies today use open source software, most of them struggle greatly with implementing the internal controls to coordinate their use of open source software with their patent portfolio management. This means it is quite possible that a company is seeking patent protection, or seeking to enforce patents, that read on open source software the company is using or developing — a combination of activities that would often not be considered economically rational.

via Blogs from the Outercurve Foundation – Open Source — The Last Patent Defense?.

The drafters of open source licenses intended to use the terms of those licenses to win a war against software patents, and whether they can do that remains to be seen, but in the meantime, don’t pass up the opportunity to use the principles of open source licensing to win your battles as well.

Patent assertion entities (patent trolls) typically do not make any kind of product for the above advise to be of any use.