There’s some fantastic back and forth between Chicago law professor Richard Epstein (a Cato adjunct scholar) and Berkeley law professor Peter Menell about the similarities and differences between physical property and what’s often called intellectual property—patents and copyrights. The exchange is a response to Menell’s previous contribution to Regulation.

I think Menell has the better of the argument. They both devote a considerable amount of ink to the eBay v. MercExchange, which centered around the question of when it’s appropriate to grant injunctions for patent infringement. Epstein has generally advocated a rule that grants injunctions more freely, arguing that this creates more certainty for the patent holder. Menell, in contrast, has argued that damages are often more appropriate.

The reason this matters is that if an injunction is granted, it can often drive the losing party into bankruptcy. In 2006, for example, Research in Motion, makers of the popular BlackBerry mobile device, was forced to pay $612 million to a company called NTP that had no employees, no products, and patents that were subsequently ruled invalid by the patent office. By rights, NTP shouldn’t have gotten a dime (because there was ample prior art for its “inventions”) but because RIM would have been forced to shut down its BlackBerry network before it had exhausted its appeals, NTP was able to extort hundreds of millions of dollars from the firm.

Interestingly, Epstein alludes to the biggest flaw in his argument, but doesn’t stop to ponder its implications. He writes:

This set of institutional arrangements [from real property] does not carry over perfectly to patent cases where the fact of infringement is harder to determine outside the piracy context, owing to the lack of clear boundaries that surround any patent.

This is a gross understatement. The boundaries of many patents—especially those relating to software, which is what the MercExchange case was focused on—are so fuzzy that it’s basically impossible for even the most experienced patent lawyer to predict accurately which of the hundreds of thousands of software patents in existence might be related to a given software product. Microsoft, for example, has darkly hinted that the Linux operating system had infringed several hundred software of its patents, but the company has refused to say which patents they are and the Linux develop community hasn’t been able to figure it out.

I share Epstein’s goal to create “a system of secure property rights that allows people to transact at low cost and high reliability,” but I think he fails to appreciate how completely our current patent system fails that test. In many cases, an inventor wishing to identify the patents his new invention might infringe has no low-cost or high-reliability means of doing so. This introduces uncertainty and litigation that greatly reduces the potential rewards for inventive activity. Strengthening these vague patents even further by making injunctions even easier to obtain will only make the problem worse, because the disincentives created by the patent system will be magnified.

It’s also worth noting the important contrast between patents and physical property: if a court fails to grant you an injunction against someone who’s using your land, you are thereby deprived of the opportunity to use the land yourself. In contrast, if the court fails to grant an injunction against a patent infringer, you have lost nothing other than potential licensing revenues. This means that unlike with physical property, there’s no compelling reason to impose the potentially devastating remedy of an injunction any earlier than absolutely necessary.