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engine - 5:57 pm on Oct 29, 2010 (gmt 0)
Facebook Ad-Targeting Patent Application [news.cnet.com]
Earlier this month, Facebook filed for a patent to further hone its ad-targeting technology so that ads can be based on what a user's friends interests may be. The reason for this, it appears, is so that Facebook can better serve ads toward users who have not filled out their profiles with enough information for traditional ad targeting.
Facebook calls this second-degree targeting "inferential."