Alf Peake wrote:
> 
> When this HooHa started I was under the impression that the algorithm
> was patented _after_ CS produced the GIF format but before Unisys was
> involved. I was wrong?

Digging out books...

1984 - LZW compression invented and written up in IEEE Computer
1985 - LZW patent approved
1986 - Sperry (patent holder) merged with Burroughs to form Unisys, not
quite a purchase like I remembered
1987 - CompuServe creates GIF
1993 - Unisys becomes aware that GIF uses LZW compression

This paraphrased from Encyclopedia of Graphics File Formats, 2nd ed.

-Mark Gordn

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