This shows, yet again, is that software patents do not constitute a functioning property system. What are the affordances of a property system? A big one is th

This shows, yet again, is that software patents do not constitute a functioning property system. What are the affordances of a property system? A big one is that it provides reasonable certainty that you will have the use of something you think you own. Software patents actually work against this. Lee and Mulligan (http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2016968 http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2016968) make a good case that software firms "are unable to discover the patents their activities might infringe", because software patents are not "indexable" (unlike chemical patents, which are indexable by molecular formula) . Any companies know what their patent assets are, but not their liabilities, as testified by the fact that tech companies put pro-forma statements to this effect (with suitable weasel wording) in their SEC filings. Now we are seeing that due to the app store model, this risk is propagated to ordinary customers.