From: smb@research.att.com
Date: Fri, 1 Apr 94 08:24:56 PST
To: "Alan (Miburi-san) Wexelblat" <wex@media.mit.edu>
Subject: Re: Patent expiration
Message-ID: <9404011624.AA09937@toad.com>
MIME-Version: 1.0
Content-Type: text/plain


	 Someone has just pointed out to me that the basic PKP patents (D-H
	 especially) expire relatively soon now (the D-H patent was issued in 1
	980).

	 Seems to me this is a strong motivation for the gov to get Clipper in 
	place
	 now; three years from now all the places that won't use PGP because of
	 legal
	 tangles will be able to use it free and clear!

	 --Alan

No.  The basic patent on public key cryptography and the patent on
Diffie-Hellman key exchange expire in 1997 (the former on April 28;
the latter on August 18).  PGP uses RSA, which is protected until
September 19, 2000.