Ark42 asks: "Did the Unisys patent on LZW expire back on Dec 10, 2002? Does that mean we can all write GIF software royalty free now? From what I can gather, Unisys only lists patent number 4,558,302 for covering LZW, which was filed on Jun 20, 1983 and issued on Dec 10, 1985. According to this site patents filed after Jun 7, 1995 last 20 years from the file date, and patents on or before then last 17 years from the issue date. That means the LZW patent expired on Dec 10, 2002. Am I missing anything?" A deadline of 2003 was given in this earlier Slashdot article. Assuming .GIFs can't follow in the footsteps of Mickey Mouse, will the popular image format now be "web safe"?