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1.1     ! root        1: 
        !             2: Concerning the relationship between dmsdos and patents I keep receiving mail 
        !             3: like this one... 
        !             4: 
        !             5: > In article <[email protected]> you wrote:
        !             6: > : dmsdos 0.9.0 has just been released. It supports read and write access to
        !             7: > : compressed dos filesystems [...]
        !             8: > 
        !             9: > I think you should make sure no patents are violated. I am afraid that you
        !            10: > MUST get permission to distribute your code. I wish it was impossible
        !            11: > to get a software patent, but unfortunately companies do receive these
        !            12: > patents. There are many patents in encryption and compression technology!
        !            13: > [...]
        !            14: > Again, I wish it was possible/legal to write a free variant for every
        !            15: > existing commercial variant. Unfortunately it is not always possible.
        !            16: 
        !            17: Let me say some gereral things about this. The patent problem is indeed as 
        !            18: old as the first dmsdos version, which was released approximately three 
        !            19: years ago.
        !            20: 
        !            21: First, please allow me to correct some statements that are not litterally
        !            22: written above, but that sound like a misunderstanding. Dmsdos is not a 
        !            23: "free variant" of an "existing commercial variant". Even both "free" and 
        !            24: "variant" are wrong. Dmsdos is not free, but copyrighted and distributed 
        !            25: under the GPL. 
        !            26: 
        !            27: Dmsdos also is not a "variant" of some commercially available software
        !            28: package. It is just a tool that makes it possible to read from and write
        !            29: to some variants of compressed dos filesystems. Dmsdos is surely not a
        !            30: filesystem compression software package like stacker and doublespace, as 
        !            31: such a package needs a lot of more software e.g. all kinds of creation and 
        !            32: maintainance tools. I know it would be nice to have them under Linux, but 
        !            33: I won't write them for well known reasons.
        !            34: 
        !            35: If you follow the dmsdos history, i.e. the dmsdos documentation of older
        !            36: releases, there have always been some comments on the possibility of patent 
        !            37: problems mentioned in the documentation, and thus some features users liked
        !            38: to have in dmsdos were not implemented. Not because I knew they are 
        !            39: forbidden by patent but because I thought they *might* be covered by a 
        !            40: patent.
        !            41: 
        !            42: Yes, I did contact the respective companies (no need to say which ones :) )
        !            43: for legal issues and, of course, I asked whether they were willing to help 
        !            44: developing the code by providing documentation about their filesystem. 
        !            45: So what? When I really had luck and got an answer, it was of no value. A 
        !            46: stripped down version of one answer was published once in the dmsdos 
        !            47: documentation. I removed the name of the company and the name of the person 
        !            48: since I didn't want to blame one person. But I wanted to show the level 
        !            49: of interest of these companies - on the one hand in support and cooperation,
        !            50: and on the other hand in a Linux version of their code. It was absolutely 
        !            51: zero.
        !            52: 
        !            53: So I did my own research. It was surely not exhaustive. Patents are things
        !            54: for lawyers, but I'm not a lawyer myself and I don't have the money to
        !            55: get a bunch of lawyers study all the software patents concerning data 
        !            56: compression. Furthermore, I don't earn any penny with dmsdos.
        !            57: 
        !            58: It lead to the result that there are a lot of patented compression
        !            59: algorithms. Also the compression algorithms that the original dos software
        !            60: uses for filesystem compression are covered by patents. So what. Dmsdos
        !            61: doesn't use them. Dmsdos was developed without official documentation, and 
        !            62: it turned out that its compression algorithm even reached a higher 
        !            63: compression ratio (but was much slower).
        !            64: 
        !            65: I still tried to contact the companies, rarely, but it became more and more 
        !            66: boring. I must admit that I gave it up some time ago. I also must admit
        !            67: that I didn't add all the patent problem related stuff to the dmsdos
        !            68: documentation when I rewrote it some day. I considered it simply dead.
        !            69: This implies that some features are still missing in dmsdos and will
        !            70: probably never be added because I don't just want to be exposed to the
        !            71: risk of violating a software patent and provoking a company owning it.
        !            72: The community of dmsdos users on the net seem to have accepted this.
        !            73: 
        !            74: I also must say that dmsdos is not at all fully my own work. I just happen
        !            75: to maintain the code currently, and I'm not doing this on my own. The 
        !            76: documentation used to implement dmsdos came from a lot of people on the
        !            77: net and even from a previous sample implementation(*) that was released under
        !            78: the GPL. If you know the GPL you also know that it has a very restrictive
        !            79: patent section, so I considered this quite safe.
        !            80: 
        !            81: In fact, the compression and decompression routines in dmsdos are something
        !            82: like a collection of parts of free or GPL'd software. Most of them have
        !            83: meanwhile been rewritten from scratch for better performance. They use very
        !            84: common compression techniques. And you don't receive a patent for something 
        !            85: that is well known. You can receive a patent, e.g. for a special, highly 
        !            86: optimized algorithm, but, let me repeat this, dmsdos does not use any 
        !            87: patented compression algorithms.
        !            88: 
        !            89: So what can I do? Just throw away the dmsdos code and remove it from
        !            90: the servers? This is like a snail going back into its house and staying
        !            91: there though nothing is happening outside. Just continue trying to contact 
        !            92: the companies? I'm bored by their answers if I happen to get one. Sorry.
        !            93: Just giving dmsdos maintainance into the hand of someone else? Heh. That 
        !            94: would solve the problem probably for me, but not for others.
        !            95: 
        !            96: If you just happen to know more about the patent situation than me, please
        !            97: let me know.
        !            98: 
        !            99: 
        !           100: (*) ftp://sunsite.unc.edu/pub/Linux/system/Filesystems/dosfs/thsfs.tgz
        !           101:     written 1994 by Thomas Scheuermann (current email address unknown)

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