The US Library of Congress has approved the use of 'jail-breaking' procedures on mobile phones.
The practice of removing restrictions on third-party applications falls under 'fair use' guidelines that allow limited public use of copyrighted content, according to the US Copyright Office, which is part of the Library of Congress.
The ruling (PDF) singled out a case involving Apple's iPhone, which has been a popular target for jail-breaking since its release. The procedure has been most commonly used to install third-party apps not offered through the App Store.
Apple has long argued that the use of such procedures is a violation of copyright law, but the Copyright Office ruled that individual users have the right to modify their handsets.
"The user is not engaging in any commercial exploitation of the firmware," the Library of Congress wrote in its decision. "At least not when the jail-breaking is done for the user's own private use of the device."
The ruling was hailed as a victory by the Electronic Frontier Foundation (EFF) and other advocacy groups.
"The Copyright Office and Librarian of Congress have taken three important steps today to mitigate some of the harms caused by the Digital Millennium Copyright Act," said EFF civil liberties director Jennifer Granick.
"We are thrilled to have helped free jail-breakers, unlockers and vidders from this law's overbroad reach."
Rights group Public Knowledge also threw its support behind the decision, suggesting that such matters should be reviewed more frequently.
"We are pleased that the Copyright Office will allow consumers the freedom to have more choice of applications for their iPhones," wrote Sherwin Siy, deputy legal director at Public Knowledge. "This type of decision is long overdue."
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