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

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.