Re: RC4 Legal Issues

[Phil Karn <karn@qualcomm.com>]

>A trade secret is just that, a secret.  For parties unrelated to the
>holder of the secret, once it's no longer a secret, it's not a secret,
>and the former holder of the secret has no protection at all.  In
>other words, if you're not, say, a BSAFE licensee, you are free to use
>the alleged RC4 algorithm.

This was my understanding *before* the recent jury decision in the
Microsoft vs Stac Electronics countersuit. When Stac sued Microsoft
for infringing their patents on disk compression, Microsoft
countersued Stac for trade secret infringement for having
reverse-engineered some hidden system calls in MS-DOS. Not only did
the jury uphold Stac's bogus software patent, but they also found in
favor of Microsoft on their ridiculous trade secret accusation!

Needless to say, this creates a very troubling precedent. Now you can
now apparently infringe a trade secret merely by examining fully
public information (e.g., commercially available object code.)

Phil