I talked to a lawyer very recently about this. She does not specialize in patent law but does deal with it. The situation is confusing and fluid. Here is what I think I heard, ommiting occasional caveats: If the patent office knows of prior art (as indicated in some publicat ion)it will not issue a patent. If it does not know then it may issue the patent. Etc. Note that the patent office itself has a publication for stuff that you don't want to patent. I know of no better way to get something into their files.