Compression Patents

Software patents have had a huge impact in the field of data compression with most areas of compression being covered by at least one patent. This page contains a list of SOME of the data compression patents that exist.

• Data compression patents sorted by number
• Data compression patents sorted by coverage
• Notes from the comp.compression FAQ

The information in these compression patent pages is mostly derived from the comp.compression FAQ. This in turn was partly derived from the Patent List maintained by the League for Programming Freedom (now no longer in existence). See also this patent list which is maintained by Michael Ernst.

LZRW Algorithms And Patents

It is possible that the algorithms LZRW1, LZRW1-A, LZRW2, LZRW3, and LZRW3-A may be partially or fully covered by one or more of the following patents:

• US Patent 4701745 - The Waterworth LZ77 Patent.
• US Patent 5049881 - Gibson and Graybill LZ77 patent.
• US Patent 5051745 - Phil Katz LZ77 patent.
• US Patent 5140321 - Robert Jung LZ77 limited search patent.

The LZRW5 algorithm may be impacted by at least the following patents:

• US Patent 4464650 - Original LZ78 patent.
• US Patent 4558302 - The LZW patent.
• US Patent 4814746 - IBM's LZW patent.

Other patents may apply to these and other algorithms. Proceed with caution.