Various Microsoft products provide read/write capability and/or other LZW capability covered by Unisys-owned U.S. patents 4,558,302, B1 4,558,302 and foreign counterpart patents. Although Microsoft is licensed under these patents, Microsoft’s license does not extend to software developers or third parties who use Microsoft toolkit, language, development or operating system products to provide GIF read/write and/or any other LZW capability in their own products ( e.g., by way of DLLs and APIs). Licensing information can be obtained by contacting Unisys at the following address:

Unisys Corporation
Welch Licensing Dept. - MSC1SW19
Township Line and Union Meeting Roads
P.O. Box 500
Blue Bell, PA 19424-0001
Fax: (215) 986-3090

Inquiry may also be made via the Unisys Web site,

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