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Challenge-Response: Patent Fireworks!

A timely reminder for the European Commission, while it considers permitting software patents.

In the US, software patents have been permitted for years, with hilarious results. Here’s a good example.

Back in 1997-98, spam was a minor irritant, but the practice of ‘listbombing’ (forge-subscribing one’s enemies to lots of mailing lists) was more troublesome. As a result, several mailing-list manager programs like Majordomo added challenge-response to their subscription process; this is why, when you sign up for a list, you have to click on a link in the mail you get, to ‘confirm’ you really asked to be signed up. (Here’s a mail detailing how LISTSERV had this feature in March 1996.)

All very clever, and it solved the problem nicely.

Some bright sparks then noticed this, and decided it was non-obvious somehow to apply this to spam filtering. They overlooked the prior art (more listed here) and registered some patents.

Fast-forward to 2003, and we see that there are now no less than three pretty-much-identical anti-spam C-R patents which have been granted:

Oops! Where’s the popcorn?

(Thanks to this posting from RFG for spotting this.)

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