The US House of Representatives approved a bill Tuesday that would allow cell phone customers to unlock their devices for use on competitors' networks.

Passed by a 295-114 vote, the Unlocking Consumer Choice and Wireless Competition Act would repeal a 2012 decision by the Library of Congress that made cell phone unlocking a violation of the 1998 Digital Millennium Copyright Act. The DMCA, which prohibits Americans from "circumventing" technologies that protect copyrighted works, gives the Library of Congress the authority to grant exemptions.

Unlocking cell phones allows handsets to be used on a wireless network other than that of the originating carrier. It's a process that wireless carriers are usually willing to accommodate once the customer's wireless contract has been fulfilled. But the process became illegal last year when the Library of Congress opted not to renew a DMCA exemption, which it granted in 2006 and 2010. The change caused a stir in the wireless community and lead to an online petition that garnered some 114,322 signatures before winning the president's support last March.

While emphasizing that the bill would legalize individual unlocking, the bill included a prohibition against bulk unlocking of devices for the purpose of resale, according to a summary of the bill.

"This legislation allows any individual who wishes to unlock their cell phone for personal use to seek help from others without violating anti-circumvention provisions and clarifies that this bill does not permit the unlocking of cell phones for the purpose of bulk resale," the summary states.

The inclusion of a clause in the bill prohibiting bulk unlocking drew criticism from consumer watchdogs. Consumer advocacy group Public Knowledge withdrew its support, saying that "language recently added to the bill could be interpreted to make future unlocking efforts more difficult."

The Electronic Frontier Foundation also dropped its support of the bill, saying that that the new legislation "sends two dangerous signals: (1) that Congress is OK with using copyright as an excuse to inhibit certain business models, even if the business isn't actually infringing anyone's copyright; and (2) that Congress still doesn't understand the collateral damage Section 1201 [of the DMCA] is causing. For example, bulk unlocking not only benefits consumers, it's good for the environment -- unlocking allows re-use, and that means less electronic waste."

Senate Judiciary Chairman Patrick Leahy has already introduced his own unlocking bill, although his support for the bulk unlocking prohibition is uncertain.

The five major US wireless carriers reached a deal late last year with the Federal Communications Commission to unlock customers' handsets, but only after the terms of their contract had been fulfilled. The deal also states that carriers can charge non-customers a fee for unlocking a phone.