A Unisys press release explaining their beliefs regarding licensing required to use GIF technology in your products. As of this posting (8/2003) the US patents appear to have expired, but there are European and Japanese patents will not expire until some time in 2004.

http://www.unisys.com/about__unisys/lzw/

Drew Scott Daniels was attempting to find out when
all the LZW patents all over the world were
going to expire. This is not as easy as you might think!
Drew was kind enough to forward links to the message
boards where the question was posted. To follow the thread,
go to the bottom of the page and click on the Next
by thread link.

http://lists.debian.org/debian-legal/2003/debian-legal-200303/msg00526.html

The rules from Microsoft on what you can and can’t distribute from Windows Media 9.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnwmt/html/RedisWMedC.asp

A position paper from Dr. Klaus Jung and Prof. RuediSeiler, representing Algo Vision LuraTech GmbH. They show in some detail that Forgent’s claims on a patent that covers JPEG are not valid.

Reader John F. said: Goodbye Forgent and your lawyer pals at Jenkens and Gilchrist! We’ll see who has the last laugh on this deal, in the early part of 2003 this story has been very quiet.

http://www.algovision-luratech.com/company/news/statement_seiler_jung_en.pdf

The New York Times covers the Forgent JPEG case. A good overview of the case.

http://www.nytimes.com/2002/07/29/technology/29JPEG.html

Forgent explains their position with respect to the infamous ‘672 patent.

http://www.corporate-ir.net/ireye/ir_site.zhtml?ticker=FORG&script=410&layout=-6&item_id=3
14044

An article on CNET regarding the Forgent JPEG patent. This article brings up the allegation that one of the patent authors sat on a JPEG committee.

http://news.com.com/2100-1001-945686.html

The Register UK reports that the ISO may withdraw the JPEG image format standard if the Forgent ‘672 patent holds up.

http://www.theregister.co.uk/content/archive/26339.html

ExtremeTech reports on the Forgent JPEG patent case.

http://www.extremetech.com/article2/0,3973,389261,00.asp

Wired reports on the Forgent JPEG patent case.

http://www.wired.com/news/business/0,1367,53981,00.html

The ISO committee responsible for the JPEG standard would like to track down prior art that might invalidate the Forgent patent.

http://www.jpeg.org/newsrel1.html

The folks at Zeosync have been making some pretty bold claims regarding their yet-to-be-shown compressin tools. This patent application might open the door a bit.

http://l2.espacenet.com/dips/viewer?PN=WO0219536&CY=ep&LG=en&DB=EPD

One of the earliest patents regarding fractal compression. Issued 10 July 1990, assigned to Iterated Systems.

A fundamental patent for fractal image compression assigned to Iterated Systems. This patent was issued 12 November 1991.

A fractal compression patent held by Iterated Systems, Inc. This appears to be a very fundamental patent issued 13 September 1994.

An arithmetic coding patent which appears to be currently assigned to Samsung.

This is reportedly the Fraunhofer patent covering the MP3 compression algorithm.

http://www.mp3-tech.org/docs/5579430.pdf

Ross Williams has provided a list of compression patents here. Might help, although the site is a few years old and doesn’t appear to have been updated recently.

http://www.ross.net/compression/patents_by_coverage.html

Some information on LZW, it looks as though this has info on Licensing, but I’m not sure. All information is in Japanese.

http://www.unisys.co.jp/LZW/

The comp.compression FAQ attempts to shed some light on this topic.

http://www.faqs.org/faqs/compression-faq/part1/section-7.html