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 of 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