I just heard that Unisys is now insisting that implementors of GIF
get a license from them and pay them a royalty. Seems GIF uses LZW
compression, for which Unisys claims to have a patent.
My recollection is that there are rules about use of patented
technology in Internet standards -- something to do about the
patent owner has to make them available to all for a reasonable
fee. I don't know whether Unisys has done this or not.
So I suggest that image/gif be removed from the Full Standard
version of MIME. The content-type registration will of course
remain in effect, but it probably needs to be amended to include
a warning to the effect that image/gif employs technology to
which someone claims a patent.
Let's stamp out software patents in our lifetime.