Combination Spam Fighters

from the better-approach dept

I've made no secret of my dislike for challenge-response systems. I think that they tend to create a lot of "false positives", such that anyone who is a legitimate emailer who receives a challenge and doesn't respond has basically been blocked by the spam filter. However, I am intrigued by the idea of a combination approach, such as the one being built by Deerfield. They're working on a product that combines SpamAssassin with a challenge response system, though, from my reading, I think they have it backwards. The article suggests that it sends the challenge only to emails that make it through the SpamAssassin filters (the ones it thinks aren't spam). I'd think a more useful solution would be for it to send it to the messages that are caught in the spam filter, since those are the ones more likely to be spam. It would remove the need for the user to go and check the SpamAssassin filter for false positives, since the sender can push themselves through. This also increases the likelihood that anyone who is legitimate won't have to jump through an extra hoop to reach you. Of course, a more important question is how long until MailBlocks sends their lawyers to sue Deerfield for infringing on their challenge-response patent?