LZW patents only expired in 2003. Before that, GIF was not only patented, but the patents were actively (and often obnoxiously) enforced by Unisys. The situation was similar to that of MP3 with Frauenhofer in the late 1990s.
LZW encoding was patented, decoding was never patent encumbered. So web browsers never had to worry, since all they were doing was decompressing. For the H.264 case, decoding is also encumbered, so it's not the same situation.
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Actually, GIF was patented for a very, very long time:
http://en.wikipedia.org/wiki/Graphics_Interchange_Format#Uni...
LZW patents only expired in 2003. Before that, GIF was not only patented, but the patents were actively (and often obnoxiously) enforced by Unisys. The situation was similar to that of MP3 with Frauenhofer in the late 1990s.
LZW encoding was patented, decoding was never patent encumbered. So web browsers never had to worry, since all they were doing was decompressing. For the H.264 case, decoding is also encumbered, so it's not the same situation.