(I've not read the Yahoo patent, so I'm only presuming they apply to
DKIM - but given DKIM is mostly just DK with a fix or two and some
peripheral extras added, I'm guessing it does).
The license refers to several patent applications. As far as I can
tell there is one issued patent, 6,986,049, which probably covers DKIM
although the use of the word "domain" in the claims is confusing.
It would be nice if Yahoo offered a cleaned up version of the patent
license (unrelated to the GPL sample code) but I wouldn't wait for
them to do so.
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