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  2  $FreeBSD$
  4From: James A. Woods <>
  6>From vn Fri Dec  2 18:05:27 1988
  7Subject: Re: Looking for C source for RSA
  8Newsgroups: sci.crypt
 10# Illegitimi noncarborundum
 12Patents are a tar pit.
 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.
 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.
 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.
 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'.
 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.)
 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.  
 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.
 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.
 59From: James A. Woods <>
 60Subject: Re: Looking for C source for RSA (actually 'compress' patents)
 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".
 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.)
 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.
 77	anyway, I'm still learning about intellectual property law after
 78	several conversations from a Unisys (nee sperry) lawyer re 'compress'.
 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!)
 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]. 
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...
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.
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).
138	quite a mess, huh?  I've wanted to tell someone this stuff
139	for a long time, for posterity if nothing else.