Smartphone users throughout the U.S. lost one of their rights over the weekend, and most of them had no idea it happened. If you buy a subsidized smartphone from your carrier (the ones you can get at a discount off the standard price), it’s now illegal to unlock it without the permission of the carrier.

smartphone unlocking

The decision to ban Americans from being able to unlock their smartphones legally was handed down by the Librarian of Congress—the person also in charge of the interpretation of the Digital Millennium Copyright Act. The decision was announced (rather quietly, some in the tech community might say) in October, 90 days before it would take effect. You can read the complete document here.

The tech community is outraged that such a law could be made without the input of Congress. The White House’s We the People have started a petition to urge Congress to make unlocking smartphones legal.

“Consumers will be forced to pay exorbitant roaming fees to make calls while traveling abroad,” the petition states. “It reduces consumer choice, and decreases the resale value of devices that consumers have paid for in full.”

The petition requests for the White House to ask the Librarian of Congress to rescind the decision to ban smartphone unlocking or to “champion a bill that makes unlocking permanently legal.” At this point there are fewer than 30,000 signatures on the petition. In order for the White House to comment on it, more than 73,000 more people must sign it by Feb. 23.

The practice unlocking smartphones has been around for many years, and it’s distinct from jail-breaking a phone, which involves opening it up so that you can add non-standard apps or make other custom modifications to it. Some users unlock their smartphone so that they can take it with them to a new carrier when they switch companies. Others might opt for a popular phone that isn’t available on their network.

For example, some iPhone lovers who were on T-Mobile could buy an AT&T Inc. (NYSE:T) iPhone and unlock it so that it could be used on the T-Mobile network. The key was to buy a phone on a network that operated on the same frequency as the carrier you would be using. Since AT&T Inc. (NYSE:T) and T-Mobile use the same frequency, it was possible to unlock phones made for either network and then use them on the other network.

In the past, mobile phone carriers would generally only hand over the unlock codes for a device after a certain amount of time has passed, depending on which phone it is and which carrier you are dealing with. The one thing carriers were most concerned about is people getting a big discount on a phone (a discount that the carrier itself helped pay for) and then unlocking it and taking it to a different carrier.

It is still possible to purchase phones that are already unlocked directly from the carrier. For example, the iPhone 5 that’s available on the Verizon network already has an unlocked SIM card slot when you get it. However, smartphones that are unlocked by the carriers before you buy them are usually a lot more expensive than phones you would have to unlock yourself.