brnstnd@kramden.acf.nyu.edu (Dan Bernstein) (04/02/91)
In article <1991Apr2.003452.27382@alembic.acs.com> csu@alembic.acs.com (Dave Mack) writes: > Except that the patent-holder (Unisys, I believe) There are *two* patent holders on LZW: Unisys, through Welch's patent, and IBM, through the Miller-Wegman patent. The IBM patent covers LZW, among other things, and was filed earlier than the Sperry patent. (Yes, this does mean the Sperry patent should not have been approved.) It is *not* safe to use LZW. Unisys has been throwing disclaimers left and right for money it won't get. Despite the current market situation and various unfounded rumors, IBM has rights to LZW, and it hasn't disclaimed anything. > There is *no* problem with using software implementations of > LZW compression for anything, be it GIF encoding or news transport. No. There is a huge problem with all implementations of LZW, and the problem won't go away until 2006. ---Dan
cs4304ak@evax.arl.utexas.edu (David Richardson) (04/03/91)
In article <29014:Apr215:25:5191@kramden.acf.nyu.edu> brnstnd@kramden.acf.nyu.edu (Dan Bernstein) writes: >No. There is a huge problem with all implementations of LZW, and the >problem won't go away until 2006. Well, if IBM (or anyone else) who claims rights to LZW doesn't take positive action to enforce thier rights, the defendants in any future suit will have a good chance at proving that IBM (or whomever) abandoned thier patent. If anyone claims rights to software implimentations of LZW, I suggest they go to court real soon now, or at least give the world explicit permission to use the patent (a la Unisys). Disclaimer: I'm not a lawyer, but I play one on the net. -- David Richardson U. Texas at Arlington +1 817 856 6637 PO Box 192053 Usually hailing from: b645zax@utarlg.uta.edu Arlington, TX 76019 b645zax@utarlg.bitnet, SPAN: UTSPAN::UTADNX::UTARLG::B645ZAX -2053 USA The Lord is my shepherd, I shall not want.
dab@moxie.moxie.oswego.edu (David Alan Bozak) (04/04/91)
Dan Bernstein writes:
There are *two* patent holders on LZW: Unisys, through Welch's patent,
and IBM, through the Miller-Wegman patent. The IBM patent covers LZW,
among other things, and was filed earlier than the Sperry patent. (Yes,
this does mean the Sperry patent should not have been approved.)
ok, my question is:
has anyone a good summary of the events and arguments which have led
up to the decision for a patent to be granted to Unisys? I really
would like to find a good description of just how we ended up in the
fix we are apparently in with regard to LZW.
thanks.
-dab
--
/\ David Alan Bozak, Computer Science Department
/ \ SUNY Oswego, Oswego, NY 13126 (315) 341-2347
_____/____\_____ Internet: dab@moxie.oswego.edu
/ / \ \ or dab%moxie.oswego.edu@nisc.nyser.net
/____/ \____\ UUCP: {cornell!devvax,rutgers!sunybcs}!oswego!moxie!dabbrnstnd@kramden.acf.nyu.edu (Dan Bernstein) (04/04/91)
In article <1991Apr3.041358.6194@evax.arl.utexas.edu> cs4304ak@evax.arl.utexas.edu (David Richardson) writes: > Well, if IBM (or anyone else) who claims rights to LZW doesn't take > positive action to enforce thier rights, the defendants in any future > suit will have a good chance at proving that IBM (or whomever) abandoned > thier patent. No. Copyrighted documents and trademarks may fall into the public domain, but a patent is about as strong after 16 years of neglect as when it was new. (It is *stronger* after it has been applied commercially.) If you want citations for this, send me e-mail. Furthermore, the IBM Miller-Wegman patent was only issued two years ago. Two years is a short time in the patent business. ---Dan
6sigma2@polari.UUCP (Brian Matthews) (04/05/91)
In article <1991Apr3.041358.6194@evax.arl.utexas.edu> cs4304ak@evax.arl.utexas.edu (David Richardson) writes: |Well, if IBM (or anyone else) who claims rights to LZW doesn't take |positive action to enforce thier rights, the defendants in any future |suit will have a good chance at proving that IBM (or whomever) abandoned |thier patent. Bzzzt. Next contestant please. Patent holders don't need to take positive (or any) action to retain their patent for the full 17 years. Copyrights and trademarks can lapse into the public domain, but not patents. -- Brian L. Matthews 6sigma2@polari.UUCP
csu@alembic.acs.com (Dave Mack) (04/09/91)
In article <29014:Apr215:25:5191@kramden.acf.nyu.edu> brnstnd@kramden.acf.nyu.edu (Dan Bernstein) writes: >In article <1991Apr2.003452.27382@alembic.acs.com> csu@alembic.acs.com (Dave Mack) writes: >> Except that the patent-holder (Unisys, I believe) > >There are *two* patent holders on LZW: Unisys, through Welch's patent, >and IBM, through the Miller-Wegman patent. The IBM patent covers LZW, >among other things, and was filed earlier than the Sperry patent. (Yes, >this does mean the Sperry patent should not have been approved.) > >It is *not* safe to use LZW. Unisys has been throwing disclaimers left >and right for money it won't get. Despite the current market situation >and various unfounded rumors, IBM has rights to LZW, and it hasn't >disclaimed anything. > >> There is *no* problem with using software implementations of >> LZW compression for anything, be it GIF encoding or news transport. > >No. There is a huge problem with all implementations of LZW, and the >problem won't go away until 2006. My comments about the general use of LZW encoding may have been too sweeping - I apologize. I also include the original article which led me to believe that LZW could be generally used without threat of litigation. Please note that it primarily covers the "compress" program. A followup, which I failed to save, made additional comments about the use of LZW in GIF encoding, but I'll rely on someone else to provide that. ------------------------------------------------------------------------ From uunet!zephyr.ens.tek.com!uw-beaver!mit-eddie!wuarchive!usc!ucsd!ucbvax!agate!riacs!jaw Wed Aug 1 15:06:59 EDT 1990 Article: 1282 of gnu.misc.discuss Path: alembic!uunet!zephyr.ens.tek.com!uw-beaver!mit-eddie!wuarchive!usc!ucsd!ucbvax!agate!riacs!jaw From: jaw@riacs.edu (James A. Woods) Newsgroups: gnu.misc.discuss Subject: Sperry patent #4,558,302 does *not* affect 'compress' Keywords: data compression, algorithm, patent Message-ID: <1990Jul31.220935.1424@riacs.edu> Date: 31 Jul 90 22:09:35 GMT Organization: RIACS, NASA Ames Research Center Lines: 69 # "The chief defect of Henry King Was chewing little bits of string." -- Hilaire Belloc, Cautionary Tales [1907] As a co-author of 'compress' who has had contact with an attorney for Unisys (nee Sperry), I would like to relay a very basic admission from Unisys that noncommercial use of 'compress' is perfectly legal. 'Compress' is also commercially distributed by AT&T as part of Unix System 5 release 4, with no further restrictions placed upon the use of the binary, as far as I am aware. From conversations with Professor Abraham Lempel and others, it appears that neither AT&T, Sun Microsystems, Hewlett Packard, nor IBM are paying any sort of license fees to Unisys in conjunction with patent #4,558,302. It may be true that some organizations are paying fees for data compression technology licensed from one or more of the many holders of compression patents, but this is all independent from 'compress'. In particular, I received a letter at NASA dated October 1, 1987 from John B. Sowell of the Unisys law department, informing me for the first time that some form of LZW was patented. I naturally expressed skepticism that an algorithm could be patented (a murky legal area which remains so), stated that 'compress' is not identical to LZW, and in fact was designed, developed, and distributed before the ink on the patent was dry. Several telephone conversations later, Mr. Sowell intimated that they would *not* seek any fees from users of 'compress' but instead were signing licensees for hardware implementations of LZW. So, regardless of what you believe about a shady legal area, if anyone from Unisys contacts you to extract tribute for the use of 'compress', please tell them that, first, it is not theirs to begin with, and, second, there is someone who will testify in court about the conversation above. It is not even clear if anyone can "own" 'compress', since original developer Spencer Thomas, myself, and others placed the code in the public domain long before the adoption of the Berne copyright convention. In light of the events above, it seems that the Free Software Foundation is being unduly paranoid about the use of 'compress'. Now I can well believe that FSF is more likely to be a legal target than a behemoth like AT&T, but if they are simply redistributing untouched free software developed years ago in the public sector, I see no problem. Aside: I am investigating, possibly for a case history to be recycled to USENET, the particulars of data compression patents. I am aware of the following patents: IBM's Miller-Wegman LZ variant, those of Telcor and ACT [losing candidates for the British Telecom modem standard], James A. Storer's work on limited lookahead as explicated in his text "Data Compression (methods and theory)", Computer Science Press, 1988, and the various patents pending associated with the Fiala and Greene CACM article of April, 1989 on textual substitution methods. If you have any lore, send it this way. Sincerely, James A. Woods NASA Ames Research Center (RIACS) jaw@riacs.edu (or ames!jaw) P.S. The algorithm patent issue certainly is a "topic A" at the moment. One useful reference is the review article by Anthony and Colwell -- "Litigating the Validity and Infringement of Software Patents" in Washington and Lee Law Review, volume 41, fall 1984. I know Robert Colwell personally. As a practicing patent attorney, he tells me that, at a minimum, use of an invention "for research purposes" is legitimate.