w8sdz@brl-smoke.ARPA (Keith B. Petersen ) (05/10/87)
After announcing the availability of a recent update of SEA's ARC program, I received the following message which raises serious doubts as to the validity of the copyrights of SEA, Phil Katz, and Vernon Berg's ARC programs and well as other LZW-type compression programs and the status of the popular Unix "compress" program. --forwarded message-- To: Keith Petersen <W8SDZ@SIMTEL20.ARPA> Re: Message for the authors of ARC I don't know how to get in touch with the authors of ARC (I didn't see any addresses in INFO-IBMPC), but since you seem to be posting information about new versions, etc., I thought that you might be able to forward the following mail to them. 1) The correct spelling of the name is Ziv. So you should call it Lempel-Ziv (or Ziv-Lempel because that was the order of the author's names in the original paper) encoding. 2) The original Ziv-Lempel method is patented (#4,464,650 -- Willard Eastman, Abraham Lempel, Jacob Ziv, Martin Cohen) assigned to Sperry Univac (now Unisys). Since the Welch modifications are to this method, I would think that some sort of license agreement from Unisys would be necessary (this is really only a practical problem for commercial customers). Does such an agreement exist? --end forwarded message-- -- Keith Petersen Arpa: W8SDZ@SIMTEL20.ARPA Uucp: {bellcore,decwrl,harvard,lll-crg,ucbvax,uw-beaver}!simtel20.arpa!w8sdz GEnie Mail: W8SDZ