Message-ID: 14404.25809.363861.453811@kurtz.fake
To: Tom Lane <tgl@sss.pgh.pa.us>
Subject: Re: libtiff 3.5.3 release.
From: "Michael L. Welles" <mike@onshore.com>
Date: Tue, 30 Nov 1999 19:08:23 -0500 (EST)
Cc: izumi@pinoko.berkeley.edu, tiff@olympiakos.com
In-Reply-To: <22488.944003264@sss.pgh.pa.us>
References: <199911302253.OAA07994@moica.berkeley.edu><22488.944003264@sss.pgh.pa.us>
Reply-To: mike@onshore.com
Sender: owner-tiff@olympiakos.com



Richard Stallman informed Frank and I that the FSF's lawyers see LZW
compression as encumbered by the patent: 

>    My understanding is that LZW decompression is not encumbered by the LZW
>    patent, but that LZW compression is.  Do you know if that is true?
>
> That is how our lawyers read the patent, and so that is what we
> base our actions on.

Tom Lane writes:
 > Izumi Ohzawa <izumi@pinoko.berkeley.edu> writes:
 > > Now, I need a solid reference that LZW decompression is not
 > > covered by the LZW patent.  Nothing I have read, except for opinions
 > > or second-hand quotes at various forums, clearly indicates
 > > that decompression is not part of the patent.
 > 
 > > Especially, does anyone have written views from the Unisys itself
 > > on this?
 > 
 > Unisys' view is perfectly clear: they claim that decompression-only
 > software *is* covered by the patent.  (They have a webpage giving their
 > version of reality at www.unisys.com, check there for an exact quote.)
 > 
 > There are a number of qualified people who think that Unisys'
 > interpretation wouldn't hold up in court, and that a court would say
 > that decompression-only software isn't covered.  But AFAIK there's
 > been no test case to find out.  Do you want to be the test case?
 > 
 > > Regardless of what court may or may not rule in the end, that
 > > doesn't matter.  Most of us here, I think, just don't want to
 > > hear from Unisys counsels, ever.
 > 
 > Yup.  That's why I'm not shipping either LZW compression or
 > decompression code in libjpeg these days.  It was a relatively painless
 > decision for me, because GIF-reading was never a critical part of
 > libjpeg, but I can see that dropping the LZW decompressor would be
 > crippling for libtiff :-(.  Don't have any good advice...
 > 
 >                      regards, tom lane
 >                      organizer, Independent JPEG Group
 > 

------------------------------------------------------          
M. L.  Welles                   mike@onShore.com
-------------------------------------------------------

