In response to Nillay I left this brief comment:<p>Nilay, I think your patent exchange misses a key point in software. No one reads them. Nobody reads patents. In fact, go talk to a Microsoft and Apple engineer about patents and they'll tell you that not only do they not read them, their corporate policy does NOT allow engineers to read patents. Apparently it drastically increases the likelihood of treble damages for the company.<p>You give the PageRank example, missing though that there was work from IBM that was very similar. See this classic paper, "Authorative Sources in a HyperLinked Environment" from 1997(<a href="http://www.cs.cornell.edu/home..." rel="nofollow">http://www.cs.cornell.edu/home...</a>. The genius/luck of Google was continuing to push this idea of search, when no one else seemed all that interested (recall AltaVista, Yahoo, and Lycos had all seen Google's results and were offered a chance to buy the company -- they all passed. Their genius was in persisting and not giving up and getting their PhD.)<p>The Apple patent you show is an example of what I call, "Being the first to ask the question". I'm not sure how else you'd solve the problem besides how they did it. It's the obvious way to do it. They probably lucked out because they were the first company to be faced with the question. This has become rampant in the mobile industry. Whenever you have a new form factor, there are new problems. They aren't necessarily hard, but they're new. And the fact that they're new problems means there's no prior art. You can suddenly file a bunch of patents based on your solutions, 99% of whcih are the same solutions the guy across the street would come up with in six months when he happens to hit the same problem. That's not innovation -- that's blocking innovation as it ensures your six month advantage becomes a 15 year advantage (or however long patents expire).<p>Nobody in SW reads patents. Furthermore patents are actually very hard for those in the field to follow. They use non-standard jargon. I'd much rather read source code or a CS paper to get the ideas -- as those are usually written just by the actual developer, and not translated by the lawyer.<p>And an unrelated, but important point, IMO. SW, unlike most other endeavors, is something that people rapidly build on. People still take aspirin today, in the exact same form as 50 years ago. No one uses a piece of software in the exact same form as 50 years ago. The closest is probably vi, but even vi has had significant code churn over the past 30 years -- it's quite possible that it currently shares no lines of code from the original version. SW evolves rapidly. Patents seem much better suited for fields where inventions can stand on their own for significant periods of time.