Z:gnu-www-ja-danger-of-software-patents--7376ee-For instance, in the 80s and 9/en

For instance, in the 80s and 90s, there was a patent on &ldquo;natural order recalculation&rdquo; in spreadsheets. Somebody once asked me for a copy of it, so I looked in our computer file which lists the patent numbers. And then I pulled out the drawer to get the paper copy of this patent and xeroxed it and sent it to him. And when he got it, he said, &ldquo;I think you sent me the wrong patent. This is something about compilers.&rdquo; So I thought maybe our file has the wrong number in it. I looked in it again, and sure enough it said, &ldquo;A method for compiling formulas into object code.&rdquo; So I started to read it to see if it was indeed the wrong patent. I read the claims, and sure enough it was the natural order recalculation patent, but it didn't use those terms. It didn't use the term &ldquo;spreadsheet&rdquo;. In fact, what the patent prohibited was dozens of different ways of implementing topological sort&mdash;all the ways they could think of. But I don't think it used the term &ldquo;topological sort&rdquo;.