The Librarian of Congress and US Copyright Office just proposed new rules that will give consumers and independent repair experts wide latitude to legally hack embedded software on their devices in order to repair or maintain them. This exemption to copyright law will apply to smartphones, tractors, cars, smart home appliances, and many other devices.

The move is a landmark win for the "right to repair" movement; essentially, the federal government has ruled that consumers and repair professionals have the right to legally hack the firmware of "lawfully acquired" devices for the "maintenance" and "repair" of that device. Previously, it was legal to hack tractor firmware for the purposes of repair; it is now legal to hack many consumer electronics.

Specifically, it allows breaking digital rights management (DRM) and embedded software locks for "the maintenance of a device or system … in order to make it work in accordance with its original specifications" or for "the repair of a device or system … to a state of working in accordance with its original specifications."

New copyright rules are released once every three years by the US Copyright Office and are officially put into place by the Librarian of Congress. These are considered "exemptions" to section 1201 of US copyright law, and makes DRM circumvention legal in certain specific cases. The new repair exemption is broad, applies to a wide variety of devices (an exemption in 2015 applied only to tractors and farm equipment, for example), and makes clear that the federal government believes you should be legally allowed to fix the things you own.

"I read it as the ability to reset to factory settings," Nathan Proctor, head of consumer rights group US PIRG's right to repair efforts, told me in an email. "That's pretty much what we've been asking for."

 While this is a huge win on a federal level, this decision does nothing to address the practicalities of what consumers and independent repair professionals face in the real world. Anti-tampering and repair DRM implemented by manufacturers has gotten increasingly difficult to circumvent, and the decision doesn't make DRM illegal, it just makes it legal for the owner of a device to bypass it for the purposes of repair.

A good way to think about this is to consider MacBook Pro repair. As Motherboard reported earlier this month, Apple has a built-in kill switch that can prevent new MacBook Pros from functioning if they have been repaired by anyone who is not authorized to do so by Apple. It uses embedded software to do this, by requiring the computer to connect to Apple's servers in order to verify that a repair is "authorized." This decision by the Copyright Office will make it legal to bypass that software lock, but actually doing it is another matter altogether.