ZDnet features an article about the had patent at AltNet http://news.zdnet.com/2100-9588_22-5534087.html . Apparantly this issue plays already for some time, now the p2p companies are threatened, becuase they use hashing to recognize files.
I find it incredibly annoying when journalists reporting on patent issues don't bother to quote the patent numbers (or patent application numbers) concerned (failure to do so probably means they haven't bothered to examine the patent or patent application themselves). In this case, a search is made doubly difficult because the patent was purchased from someone else, so a name serach can't be done. A quick keyworfd search on the USPTO web site revealed some related patents issued to Apple and Sony, but hard to identify this particular patent.
As far as I know hasing is a very old technique used to quickly look up information. The use of hashing always requires an idnetity check, because the lookup is not unique (mapping a very big amount of possibilities on a limited amount of entries). This is a fast and robust way of finding information, if the right hashing function is used.
How can this type of fundamental knowledge be patented? I am afraid this is again an example of a total failure of the current patent system. Unfortunately these ridiculous examples endanger smaller companies, open software activities amd innovation in general.
What you have to remember is that the US (and some countries which have been stupid enough to follow its lead, like Japan, Australia and now it seems India) permits patents not just on software algorithms and techniques, but also on business methods. Thus the "novel" application of a well-known and widely-used technique such as hashing to a particular field of endeavour (like file sharing on the Internet) can be patented (in the US). To be novel, there must be no published prior art - but the prior art needs to be specific to the claims of the patent. So if the patent says "use of hashing to uniquely identify files in a peer-to-peer network via IP over the Internet", then the prior art needs to describe exactly that. The Australian government recently passed legislation which tightened this test of novelty (thank goodness) by allowing separate bits of prior art which describe aspects of a patent claim to be combined to some degree when opposing a patent - but the test for novelty remains remarkably lax in the US, I beleive.
And I agree 100% with Alex Martelli - Europe and other countries must reject software, algorithmic and business method patents and thus create a powerhouse of innovation. let the US and fellow-travellers stew in their own juice - they will become powerhouses of litigation instead. Provided other countries don't recognise software and business method patents, the litigation will be confined within US borders, where resources can be productivelt spent making television dramas about attractive young patent attorneys and plodding, tram-riding patent clerks who are really brilliant physicists if only someone would recognise their potential. So yes, please write to your MP and MEP and protest against the prospect of software and business method patents in Europe. Hopefully one day within my lifetime we'll have a governemt here in Australia which will roll back the damage done to our patent system by trying to make just like the US system, just so we can conclude an unbelieveably inequitable free trade agreement with the US. But that's our problem.
Tim C
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