graeme_p - 4:32 am on Dec 1, 2005 (gmt 0)

vincevincevince,

you are right that you can not patent something that has been previously invested by someone else (prior art).

However proving the existence of prior art is quite complicated. Further more someone can still patent something built on top of your unpatented invention (an improvement to it, an invention of their own that incorporates it etc.).

What we could be with is a GPL for patents.

Imagine if TCP/IP had been patented and then licensed on condition that you could not claim at patent on any technology built on it, all those silly patents of the obvious would have been impossible.