Do states have the right to make doctors' prescription data private? Or do data-mining companies have the right to gather that data and sell it? These are the questions before the U.S. Supreme Court tomorrow, as the justices hear arguments over Vermont's data-mining law. Drugmakers will be watching the case closely because they use that prescription data to market their drugs. But so will other industries that rely on data disclosure--as well as privacy advocates and free speech champions.

In 2007, Vermont's legislature passed a law designed to keep pharmacies from selling individual doctors' prescribing histories. The idea was that the data should be private, but the rule was also intended to combat the influence of pharma marketing, the Atlantic reports. The state said that it wanted to correct a "massive imbalance" in the sort of information drugmakers were able to target to particular doctors. After all, the data allowed pharma companies to identify which doctors might be most amenable to prescribing their branded drugs. And some people charge that this ability just drives up healthcare costs unnecessarily.

Read more: Supreme Court to hear data-mining arguments - FiercePharma