On Geoff’s point on MSFT, you are right to highlight the concern about facilitating cloning and how to deal with access concerns in light of the impact on investment incentives. The issue comes up in IP as well and for the fuller view of my perspective, which does not reject the role of IPRs as protecting investment incentives, see http://lawweb.colorado.edu/profiles/pubpdfs/weiser/InternetInnovation.pdf.

I’m a little unclear on what you’re saying with respect to IP and interop. I get the negative point, that the existence of IP in interfaces shouldn’t preclude application of antitrust rules, but that’s a bit of an oversimplification of MS’s position. What I don’t get are the positive implications (but I do have your article on my list of things to read . . . ). So, is the EU test (such as it is) the right one? You say IP shouldn’t be a get out of jail free card, but I fear your real conclusion is that IP shouldn’t be available on interfaces at all. And I can’t resist noting the extent to which MS did share huge amounts of information in order to make essentially all interoperability but cloning possible–which is what the competitors wanted, not surprisingly. Of course this is also not surprising, as MS could reap the rewards of a maximally-flexible and expansive platform. Frankly, I think the tradeoff between IP protection and the extremely limited set of circumstances where MS didn’t permit others to mimic its products (because doing so required, as the court’s remedy demonstrateed, wholesale distribution of MS’s IP) was a pretty fair tradeoff.

On regulating interoperability, I think an argument can be made that property rules should be abrogated in favor of liability rules when the technology exhibits declining average total costs of production over a certain period of time — i.e., approximates a natural monopoly.

On the IP and Microsoft’s antitrust issues, I always thought that not enough attention was paid to the IP of Microsoft’s competitors. Specifically, it was ridiculous for Netscape to try and establish entirely redundant marketing and distribution channels for its web browser knowing that Microsoft already had those setup for its OS.