Together with Public Knowledge and R Street, EFF filed an amicus brief today asking the Supreme Court to consider and overturn a troubling decision from the Federal Circuit. If allowed to stand, the lower court’s decision could undermine the right to use, resell, tinker with, and analyze the devices you own.

The case is called Impression Products, Inc. v. Lexmark International, Inc. and it concerns the arcane but important question of patent exhaustion. This is patent law’s version of “first sale,” the doctrine in copyright law that says that once a consumer buys a copy of a work, she owns it and can do what she wants with that copy. Patent law is similar. Once a patent owner sells a product, it cannot later claim that that product’s use or sale is infringing.

In its decision, the Federal Circuit made two important rulings. First, it said that as long as a sale is “restricted” (this could be as simple as a notice placed on disposable packaging), patent rights can be reserved by the patent owner and sale does not result in exhaustion. Second, the court ruled that an authorized sale overseas by the US patent owner does not exhaust US patent rights.

These twin rulings give patent owners a roadmap for undermining consumer ownership. As a consumer, you might not even know about what notices were placed on goods earlier in their ownership history. And because patent infringement generally does not require “intent,” you could find yourself liable for the use of goods that you purchased legally and that the patent owner has already been paid for.

Our brief explains that the Federal Circuit’s decision undermines centuries of law upholding the right of individuals to use and resell their possessions. Allowing patent owners to control goods even after sale harms liberty and autonomy. Patent owners like Lexmark (which tries to impose one-use-only limits on its ink cartridges) could try to restrict otherwise legal modifications, add-ons, resale, reverse-engineering, and security research. We hope the Supreme Court takes this case and restores our right to pwn the things we own.