Phil Karn says:
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. [...] Microsoft countersued Stac for trade secret infringement for having reverse-engineered some hidden system calls in MS-DOS. [...] the jury found in favor of Microsoft on their ridiculous trade secret accusation!
Ah, but that does make some sense. You see, Stac bought MS-DOS from Microsoft, and had to adhere to Microsoft's shrink wrap agreement. They broke the agreement they made with Microsoft when they bought the software. The person that reverse engineered RC4 obviously broke the rules and can be sued by RSA -- if anyone can ever figure out who he is. On the other hand, *I* have never signed an agreement with RSA... and I doubt that you have... Perry