IDEA licensing issues

Robert J. Hansen rjh at
Tue Jan 22 00:23:21 CET 2008

Alan Olsen wrote:
> I have been trying to find what it takes to get a license for using
> IDEA with gpg.

The first question is why you need IDEA in the first place.  It's a 
usable cipher, but it's hardly a paragon of modern design.  Better than 
brute force attacks exist against at least 4.5 of its eight rounds, and 
more may have been discovered since I last read the literature.

Assuming you need IDEA, the last I heard the terms of the patent license 
involved it being free for noncommercial use.

The easiest way to get a license for IDEA for commercial use--and 
probably the cheapest--is to buy a copy of the lowest-end PGP product. 
Presto, you have a license to use IDEA for commercial purposes.  Compile 
the idea.c code, drop it in GnuPG, and you're off to the races.

Warning: I am not an IP lawyer, I am not even the equivalent of a drunk 
IP lawyer.  Consult your own legal counsel.

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