D. J. Bernstein
Fighting patents

US patent 6185681, Zizzi, file encryption

Text of the patent
Enforcement attempt reported by Peter Avritch on sci.crypt, 2002.03.22: ``We have just been notified by counsel for the owner of this new patent that we are first in line as targets and they are seeking $25K minimum per licensee.''

Some prior art mentioned in public discussions: Glenn Everhart, 1978 (``I wrote an encrypting virtual disk driver for RSX11D back in 1978. It was published, with sources and docs on the Fall 1979 RSX SIG tapes. ... I did another for VMS in the late 80s sometime also given out freely.''); Matt Blaze, ``A cryptographic file system for UNIX,'' 1993; Matt Blaze, ``Key management in an encrypted file system,'' 1994.