Software Patents

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4,197,590: Method for dynamically viewing image elements stored in a random access memory array.

Note that some of the material about patents on this site is dated, and some of the patents mentioned may have expired in some countries.

See the User Friendly cartoon for January 7th, 2001 about the U.S. Patent Office.


The rest of this document contains the following sections:


The League for Programming Freedom is opposed to software patents.

Opinions on Software Patents, Absurd Patents and the PTO

The PTO is the United States Patent and Trademark Office. Europe has the European Patent Office.

Politicians and Software Patents

If you can get your elected representative to take a position on software patents, we would be interested in publishing it on this site.

BT's Hyperlink Patents

The GIF Situation

In December 1994, UNISYS announced it would sue developers based on their patent on LWZ compression, an integral part of the GIF specification which is used by web browsers and tools that display GIF files. The U.S. LZW Patent expired on June 20, 2003. Check out our GIF page for some history.

The MP3 music file format

MP3 (MPEG-1, Layer 3) is a very popular coder/decoder that compresses standard audio tracks into much smaller sizes without significantly compromising sound quality.

Y2K Windowing Patent

IBM patents vs. Informix

RTLinux real-time operating system patent

Geoworks' Patent on the Wireless Application Protocol (WAP)

Amazon's E-Commerce Patents

Priceline's Patent on Name-Your-Price Bidding

IPIX vs free software for image processing

Helmut Dersch of Germany has written an image processing program called "Panorama Tools". Anyone could download this free program from Helmut's web site.

IPIX have their own fisheye derived spherical VR system/software where they charge the user for every spherical VR created. IPIX have tried to intimidate Helmut Dersch by hiring a London law firm, Olswang.

See the original April 1999: email messages that describe this situation.

News item:

On January 19th, 2000, Paul Rubin nominated Helmut Dersch for the next Free Software award:

I would like to nominate Helmut Dersch for the next Free Software award. Helmut wrote the Panorama Tools suite which are really cool programs (can be used in conjunction with GIMP) that are GPL'd and are used not just for stitching panoramas, but for correcting geometric distortion and color distortions found in most digital cameras, and can also be used to flatten out pictures taken with fisheye lenses.

IPIX based their whole sleazy company on a patented program that takes fisheye images and flattens them out to look rectilinear, and then charging people $25 per license key where you need a new key for every picture; of course that flattening is just one feature of Panorama Tools. IPIX threatened Helmut with the patent and he located some articles from optics journals in the 1960's saying how to do that remapping and told IPIX to bug off. He was forced to shut down his web site temporarily but was able to reopen it without giving in to anything as far as I can tell. I'd like to be able to say that IPIX was totally hosed, but amazingly, for unfathomable reasons, people continue to buy their product.

E-Data and the Freeny Patent

In 1996, E-Data attempted to aggressively enforce the Freeny patent. Read more (from 1996).

The E-Data mentality strikes again: comments by Stephan Vladimir Bugaj (31 October 1998).

Other stuff

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