blochowi@rt9.cs.wisc.edu (Jason Blochowiak) (12/08/89)
This is reprinted without permission from Doctor Dobb's Journal #158
(December 1989), from the letters section:
--
Dear DDJ,
"LZW Data Compression," by Mark Nelson (DDJ, October 1989) is a nice
exposition on the LZW algorithm. But before your readers decide to use this
method in any application (except perhaps for purely personal use), they should
know that the algorithm is patented.
Terry Welch is listed as the inventor of U.S. Patent 4,558,302, "High
Speed Data Compression and Decompression Apparatus and Method," December 1985,
assigned to Sperry Corporation (now Unisys). The Unix compress utility and
several commercial and shareware programs are apparently infringing on this
patent (unless they have licensed it from Unisys).
If you wish use this method in a commercial setting, you should contact
Unisys for a license, or at least consult your legal counsel first.
Ray Gardner
Englewood, Colorado
Mark responds: When I wrote the LZW article I was unaware of any patent on the
algorithm. The issue has just surfaced in the press because of concern in CCITT
group 7 over approval of the BTLZ algorithm for data compression in the V.42bis
modem standard. Unisys, British Telecom, and IBM apparently all have some claim
on the algorithm. Robert Bramson, a patent attorney for Unisys, has been quoted
as saying they will license the algorithm for a one-time fee of $20,000.
I have not seen the Unisys patent, so I don't know what their specific
claims are. However, I am not aware of any attempt by Unisys to show
infringement by software developers. The BTLZ algorithm seems to be
concerned with hardware implementations. In the event that they do pursue their
claim with software developers, they will be very busy, as there are literally
hundreds of potentially infringing programs in the commercial marketplace
alone. And they certainly cannot claim a comprehensive patent of basic LZ
compression, as Terry Welch, the patent holder, was not the inventor.
I agree with Mr. Gardner that anyone who intends to use LZW compression
in a commercial product would be wise to consult legal counsel first.
Finally, I would like to suggest that DDJ reads begin a letter-writing
campaign directed to members of Congress, the ACM, and the IEEE. The current
confusion over copyright and patent issues in the software development world
only serves to stifle both creativity and productivity. At present the only way
questions regarding the validity of copyrights and patents are being answered
is through random decisions from legal proceedings. Copyright and patent laws
both need to be updated to work properly in the 1990s.
--
Somewhat interesting, eh? Perhaps it's better that Andy didn't go
commercial with ShrinkIt/GS ;)
Btw, DDJ (whom I have no affiliation with, blah, blah, ...) does tend
to have some interesting articles, even though it's IBM oriented.
--
Jason Blochowiak - blochowi@garfield.cs.wisc.edu or jason@madnix.uucp
"Education, like neurosis, begins at home." - Milton R. Sapirsteinrnf@shumv1.uucp (Rick Fincher) (12/08/89)
In article <3980@puff.cs.wisc.edu> blochowi@rt9.cs.wisc.edu (Jason Blochowiak) writes: > > Dear DDJ, > "LZW Data Compression," by Mark Nelson (DDJ, October 1989) is a nice >exposition on the LZW algorithm. But before your readers decide to use this >method in any application (except perhaps for purely personal use), they should >know that the algorithm is patented. I had always heard that algorithms couldn't be patented! Code can be copy- righted but how do you patent a concept? I know you can patent a machine, an idea for a device, and processes (chemical and biological for instance). But if you can patent algorithms who owns 16/4=4? You are taking a larger number here and reducing its size and the process is reversible (4*4 = 16), so you are essentially doing the same thing a compression algorithm is. I think programs should be protected by copyright, but this stuff is more in line with trade secrets. I doubt it will stand up in court if put to the test. Any legal types out there with any knowledge of this? Rick Fincher rnf@shumv1.ncsu.edu
saa33413@uxa.cso.uiuc.edu (12/10/89)
Try telling all that to Apple. They're the ones with the look-and-feel suits against imitators of the desktop interface used by the IIGS and Macintosh. (Ever wonder why the interface of the NeXT is so different from the Mac when Steve Jobs designed both the Mac and the NeXT? Now you know!) The idea of putting a patent on an idea is, IMHO, unconscionable, but do you think that stops the good ole boys in Cupertino? I don't think so. ------------------------------------------------------------------------------ ! Scott Alfter ! A keyboard--how quaint! ! ! ! ! ! Internet: saa33413@uxa.cso.uiuc.edu ! -- M. Scott ! ------------------------------------------------------------------------------
rnf@shumv1.uucp (Rick Fincher) (12/11/89)
In article <113300217@uxa.cso.uiuc.edu> saa33413@uxa.cso.uiuc.edu writes: > >Try telling all that to Apple. They're the ones with the look-and-feel suits >against imitators of the desktop interface used by the IIGS and Macintosh. They sued Microsoft because they licensed code to them and the thought they exceeded the license. They also feel that their additions to the XEROX interface (which Apple licensed) should be protected. They aren't faring so well in court. I can see a copyright issue in making a screen look just like someone elses. After all Apple spent millions in human interface studies when developing the Mac interface. Other companies shouldn't be able to rip off their work or their code. I think that is different from the idea of, say, a pull down menu. Other companies should just make theirs look non-identical to Apple's. >(Ever wonder why the interface of the NeXT is so different from the Mac when >Steve Jobs designed both the Mac and the NeXT? Now you know!) Actually jobs didn't design either. He stepped in to head the Mac design team after the project was started. He is responsible for for a lot of what's good AND what was bad about the original Mac. Guy Kawasaki told a story about jobs: Jobs was committed to using the 5.25 inch Twiggy drives (the ones in the original Lisa) in the Mac. All the engineers knew that 3.5 drives were the way of the future but Jobs had forbid them to even talk about it, and had banned Sony (they make the 3.5's) engin- eers from even visiting Apple. Well the engineers knew they were right so they invited the president of Sony in, behind Jobs' back, to discuss getting the drives. Well, while they were talking Jobs came in the building, so they stuffed this aged white haired-Japanese gentleman into a closet. His English was not too good and he was very confused. Jobs came in and everyone started counting holes in the ceiling, trying not to look guilty. When he left they pulled the guy out of the closet and continued the discussion. Needless to say it was eventually decided that 3.5's would be used, and they had the sup- plier on line to provide them! >The idea of >putting a patent on an idea is, IMHO, unconscionable, but do you think that >stops the good ole boys in Cupertino? I don't think so. > I agree, after all, it was a XEROX idea that spawned the Mac. I don't think Apple can win in court. I think their moves are just corporate hardball in the marketing game. They are trying to slow down all of the other guys while they try to get as mch of the post MS-DOS market as possible. The millions they spend on no-win legal actions will more than be offset by increased sales in machines. History shows that no one can stop a good idea. Rick Fincher rnf@shumv1.ncsu.edu
nicholaA@batman.moravian.EDU (Andy Nicholas) (12/13/89)
In article <3980@puff.cs.wisc.edu>, blochowi@rt9.cs.wisc.edu (Jason Blochowiak) writes: > This is reprinted without permission from Doctor Dobb's Journal #158 > (December 1989), from the letters section: [... huge thing about the legality of LZW and who owns the patent deleted ...] > Somewhat interesting, eh? Perhaps it's better that Andy didn't go > commercial with ShrinkIt/GS ;) Commercial or not doesn't matter. If I have produced a product, any product, that infringes on someone's patent, then I am liable. I don't particularly like being put in this spot, but I would assume that they (being unisys or whoever thinks they own the patent this week) would sooner go after hardware houses that use variants of LZW in their modems, government bodies like the CCITT which have approved the use of LZW variants for modems, etc. I obviously don't have $20,000 to pay for a patent license fee, nor am I likely to possess such an amount of money in the future. My system administrator says that he refuses to run a system where security is based upon obscurity. Well, in this case, I probably have to depend on such just to keep my head above water. Also, I'm not sure how enforcible such a patent is -- I haven't a clue as to legal precedence, but Mr. Welch's article was published in IEEE without a notice that a patent was pending, which some could (possibly) argue would have left people with the mistaken opinion that implementations of the algorithm would have been undertaken differently if authors had indeed known that the algorithm was in the process of being patented. Then again, ignorance of the law is no excuse. andy -- Andy Nicholas GEnie, AM-Online: shrinkit Box 435, Moravian College CompuServe: 70771,2615 Bethlehem, PA 18018 InterNET: shrinkit@moravian.edu