1 2 $FreeBSD$ 3 4From: James A. Woods <jaw@eos.arc.nasa.gov> 5 6>From vn Fri Dec 2 18:05:27 1988 7Subject: Re: Looking for C source for RSA 8Newsgroups: sci.crypt 9 10# Illegitimi noncarborundum 11 12Patents are a tar pit. 13 14A good case can be made that most are just a license to sue, and nothing 15is illegal until a patent is upheld in court. 16 17For example, if you receive netnews by means other than 'nntp', 18these very words are being modulated by 'compress', 19a variation on the patented Lempel-Ziv-Welch algorithm. 20 21Original Ziv-Lempel is patent number 4,464,650, and the more powerful 22LZW method is #4,558,302. Yet despite any similarities between 'compress' 23and LZW (the public-domain 'compress' code was designed and given to the 24world before the ink on the Welch patent was dry), no attorneys from Sperry 25(the assignee) have asked you to unplug your Usenet connection. 26 27Why? I can't speak for them, but it is possible the claims are too broad, 28or, just as bad, not broad enough. ('compress' does things not mentioned 29in the Welch patent.) Maybe they realize that they can commercialize 30LZW better by selling hardware implementations rather than by licensing 31software. Again, the LZW software delineated in the patent is *not* 32the same as that of 'compress'. 33 34At any rate, court-tested software patents are a different animal; 35corporate patents in a portfolio are usually traded like baseball cards 36to shut out small fry rather than actually be defended before 37non-technical juries. Perhaps RSA will undergo this test successfully, 38although the grant to "exclude others from making, using, or selling" 39the invention would then only apply to the U.S. (witness the 40Genentech patent of the TPA molecule in the U.S. but struck down 41in Great Britain as too broad.) 42 43The concept is still exotic for those who learned in school the rule of thumb 44that one may patent "apparatus" but not an "idea". 45Apparently this all changed in Diamond v. Diehr (1981) when the U. S. Supreme 46Court reversed itself. 47 48Scholars should consult the excellent article in the Washington and Lee 49Law Review (fall 1984, vol. 41, no. 4) by Anthony and Colwell for a 50comprehensive survey of an area which will remain murky for some time. 51 52Until the dust clears, how you approach ideas which are patented depends 53on how paranoid you are of a legal onslaught. Arbitrary? Yes. But 54the patent bar the the CCPA (Court of Customs and Patent Appeals) 55thanks you for any uncertainty as they, at least, stand to gain 56from any trouble. 57 58=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 59From: James A. Woods <jaw@eos.arc.nasa.gov> 60Subject: Re: Looking for C source for RSA (actually 'compress' patents) 61 62 In article <2042@eos.UUCP> you write: 63 >The concept is still exotic for those who learned in school the rule of thumb 64 >that one may patent "apparatus" but not an "idea". 65 66A rule of thumb that has never been completely valid, as any chemical 67engineer can tell you. (Chemical processes were among the earliest patents, 68as I recall.) 69 70 ah yes -- i date myself when relaying out-of-date advice from elderly 71 attorneys who don't even specialize in patents. one other interesting 72 class of patents include the output of optical lens design programs, 73 which yield formulae which can then fairly directly can be molded 74 into glass. although there are restrictions on patenting equations, 75 the "embedded systems" seem to fly past the legal gauntlets. 76 77 anyway, I'm still learning about intellectual property law after 78 several conversations from a Unisys (nee sperry) lawyer re 'compress'. 79 80 it's more complicated than this, but they're letting (oral 81 communication only) software versions of 'compress' slide 82 as far as licensing fees go. this includes 'arc', 'stuffit', 83 and other commercial wrappers for 'compress'. yet they are 84 signing up licensees for hardware chips. Hewlett-Packard 85 supposedly has an active vlsi project, and Unisys has 86 board-level LZW-based tape controllers. (to build LZW into 87 a disk controller would be strange, as you'd have to build 88 in a filesystem too!) 89 90 it's byzantine 91 that Unisys is in a tiff with HP regarding the patents, 92 after discovering some sort of "compress" button on some 93 HP terminal product. why? well, professor Abraham Lempel jumped 94 from being department chairman of computer science at technion in 95 Israel to sperry (where he got the first patent), but then to work 96 at Hewlett-Packard on sabbatical. the second Welch patent 97 is only weakly derivative of the first, so they want chip 98 licenses and HP relented. however, everyone agrees something 99 like the current Unix implementation is the way to go with 100 software, so HP (and UCB) long ago asked spencer Thomas and i to sign 101 off on copyright permission (although they didn't need to, it being pd). 102 Lempel, HP, and Unisys grumbles they can't make money off the 103 software since a good free implementation (not the best -- 104 i have more ideas!) escaped via Usenet. (Lempel's own pascal 105 code was apparently horribly slow.) 106 i don't follow the IBM 'arc' legal bickering; my impression 107 is that the pc folks are making money off the archiver/wrapper 108 look/feel of the thing [if ms-dos can be said to have a look and feel]. 109 110 now where is telebit with the compress firmware? in a limbo 111 netherworld, probably, with sperry still welcoming outfits 112 to sign patent licenses, a common tactic to bring other small fry 113 into the fold. the guy who crammed 12-bit compress into the modem 114 there left. also what is transpiring with 'compress' and sys 5 rel 4? 115 beats me, but if sperry got a hold of them on these issues, 116 at&t would likely re-implement another algorithm if they 117 thought 'compress' infringes. needful to say, i don't think 118 it does after the above mentioned legal conversation. 119 my own beliefs on whether algorithms should be patentable at all 120 change with the weather. if the courts finally nail down 121 patent protection for algorithms, academic publication in 122 textbooks will be somewhat at odds with the engineering world, 123 where the textbook codes will simply be a big tease to get 124 money into the patent holder coffers... 125 126 oh, if you implement LZW from the patent, you won't get 127 good rates because it doesn't mention adaptive table reset, 128 lack thereof being *the* serious deficiency of Thomas' first version. 129 130 now i know that patent law generally protects against independent 131 re-invention (like the 'xor' hash function pleasantly mentioned 132 in the patent [but not the paper]). 133 but the upshot is that if anyone ever wanted to sue us, 134 we're partially covered with 135 independently-developed twists, plus the fact that some of us work 136 in a bureaucratic morass (as contractor to a public agency in my case). 137 138 quite a mess, huh? I've wanted to tell someone this stuff 139 for a long time, for posterity if nothing else. 140 141james 142 143