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2 $FreeBSD: src/usr.bin/compress/doc/NOTES,v 1.2 2002/10/16 12:42:15 charnier Exp $
3
4 From: James A. Woods <jaw@eos.arc.nasa.gov>
5
6 >From vn Fri Dec 2 18:05:27 1988
7 Subject: Re: Looking for C source for RSA
8 Newsgroups: sci.crypt
9
10 # Illegitimi noncarborundum
11
12 Patents are a tar pit.
13
14 A good case can be made that most are just a license to sue, and nothing
15 is illegal until a patent is upheld in court.
16
17 For example, if you receive netnews by means other than 'nntp',
18 these very words are being modulated by 'compress',
19 a variation on the patented Lempel-Ziv-Welch algorithm.
20
21 Original Ziv-Lempel is patent number 4,464,650, and the more powerful
22 LZW method is #4,558,302. Yet despite any similarities between 'compress'
23 and LZW (the public-domain 'compress' code was designed and given to the
24 world 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
27 Why? I can't speak for them, but it is possible the claims are too broad,
28 or, just as bad, not broad enough. ('compress' does things not mentioned
29 in the Welch patent.) Maybe they realize that they can commercialize
30 LZW better by selling hardware implementations rather than by licensing
31 software. Again, the LZW software delineated in the patent is *not*
32 the same as that of 'compress'.
33
34 At any rate, court-tested software patents are a different animal;
35 corporate patents in a portfolio are usually traded like baseball cards
36 to shut out small fry rather than actually be defended before
37 non-technical juries. Perhaps RSA will undergo this test successfully,
38 although the grant to "exclude others from making, using, or selling"
39 the invention would then only apply to the U.S. (witness the
40 Genentech patent of the TPA molecule in the U.S. but struck down
41 in Great Britain as too broad.)
42
43 The concept is still exotic for those who learned in school the rule of thumb
44 that one may patent "apparatus" but not an "idea".
45 Apparently this all changed in Diamond v. Diehr (1981) when the U. S. Supreme
46 Court reversed itself.
47
48 Scholars should consult the excellent article in the Washington and Lee
49 Law Review (fall 1984, vol. 41, no. 4) by Anthony and Colwell for a
50 comprehensive survey of an area which will remain murky for some time.
51
52 Until the dust clears, how you approach ideas which are patented depends
53 on how paranoid you are of a legal onslaught. Arbitrary? Yes. But
54 the patent bar the the CCPA (Court of Customs and Patent Appeals)
55 thanks you for any uncertainty as they, at least, stand to gain
56 from any trouble.
57
58 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
59 From: James A. Woods <jaw@eos.arc.nasa.gov>
60 Subject: 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
66 A rule of thumb that has never been completely valid, as any chemical
67 engineer can tell you. (Chemical processes were among the earliest patents,
68 as 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
141 james
142