> regarding the LZW algorithm I was always wondering in which countries > *outside* the US Unisys holds a patent on that. > > Obviously nowhere (yet) in Europe?! Someplace else? Havent found any > information on that (such as on burnallgifs.org etc.)? This is off topic. Replies to ME please. Quote from Unisys Laywer (in answer to some preliminary questions I asked) this is from 1997 and they may by now hold many further patents on LZW. "As you may not be aware, in addition to the U.S. patent on LZW, Unisys holds patents in the United Kingdom, France Italy, Germany, Canada and Japan." On this basis they informed me that even writing LZW software in the UK would require a license. I wonder how many potential shareware authors realise that they need a license before they even BEGIN creating a GIF viewer... The Unisys patent is fairly legitimate (ie patent offices in the responsible countries had no grounds to reject it) but the effect is stiffling, which is why many of us believe that the rules should be tightened (reducing types of invention that can be patented or terms) not relaxed. Anyone not familiar with this environment should not believe for a moment that LZW would have been popularized if the patent was more widely known about -- JPEG includes support for the superior Arithmetic Coding method but your browser can't read AC JPEGs, not because it's hard but because it's patented by IBM and therefore non-free. (IBM intends to license this patent to everyone for JPEG 2000, but it remains to be seen whether the patent license will be compatible with the Gnu GPL or only BSD-like licenses) Nick.
