Paul Graham’s recent essay on his experience with software patenting has been making the rounds recently.
I broadly agree with Paul Graham’s essay on Software Patents, but I do think he underestimates the damage from patent trolls, and from what he calls the mafia-like behaviour of some patent holders. Paul has been lucky in the field he has worked in, but in the Audio and Video area there are many patent thickets. … While I was at Apple on QuickTime, there was a steady stream of patent trolls claiming that Apple should pay them royalties; enough to keep several lawyers busy, and a lot of engineers spending time working on prior art evidence demonstrations. Several potential features were excluded from QuickTime due to patent thickets. The obvious one was the Unisys LZW patent that encumbered GIF, but there were other more subtle pressures that meant adopting open source codecs was discouraged. Working on the patent license agreements for MPEG meant that technology ready to ship was deferred pending legal agreement on more than one occasion.
In my experience, that’s what happens — once a field becomes “hot”, patent trolls and other nuisance “inventors” start appearing en masse, and then you’ve got to waste a lot of time dealing with that crap.