Hi folks,
just dropping a note to the list (I'm not subscribed at the moment, so please reply direct to me if you'd like to follow up at all) to hopefully clarify a few things about the McAfee patent which has been in the news recently. I don't work at McAfee/Network Associates any more, so this is just my take on things. I'm also not a lawyer, so take my theories for what they're worth...
1. It looks like the patent was filed around the time of the Deersoft acquisition, but it was filed by the folks from the previously-existing SpamKiller desktop product group within McAfee. Bryson Gordon was that group's PM, and Thor was their chief architect/coder.
2. The claims they make, at first glance, seem to be fairly specific, and while they relate to things done in other anti-spam products, they seem to have some details in them which likely mean pretty much everything that's out there is not really infringing.
3. As has doubtless been mentioned everywhere many times -- seems to be lots of prior art.
4. As far as the SpamAssassin open source project goes, Network Associates and all McAfee employees who ever worked on the open source SpamAssassin code have signed Apache CCLAs or CLAs (http://www.apache.org/licenses/cla-corporate.txt and http://www.apache.org/licenses/cla.txt) which includes a patent-licensing section (section 4 of each document). It looks like SpamAssassin is certainly in the clear for this or any other patent of McAfee's, and anyone using the open source SpamAssassin gets the benefit of that patent license as well.
C
