I ran across an interesting article on ZDNet called Experts say Microsoft's patent quest won't go far. In the article, the author describes how many companies instruct their engineers to not perform any active searches. This is definitely true. I have spent many hours with my patent lawyer, and this is an emphatic point she makes to me repeatedly. Here is Linus's response:
"There are several reasons why engineers should not read other people's patents, only their own. And it's not a 'hide your head in the sand' issue, it's a very practical issue of it being a waste of time," Torvalds said.
For one thing, developing technology without looking at patents lets a person honestly say they developed that technology independently, which helps show that the patent in question doesn't meet the requirement of a technology not being obvious, he said. And engineers aren't likely to comprehend patents in the first place: "Unless you have a patent attorney at your side, patent language usually makes no sense."
He derided Microsoft for spreading FUD (fear, uncertainty and doubt) rather than tackling the issue forthrightly. "If Microsoft were to actually tell people what patents they claim we violate, we could either laugh in their face and show prior art, or just show them to be obvious, or we could do things differently," he said.