engine - 4:01 pm on Jan 24, 2013 (gmt 0)
In October 2012, the Librarian of Congress, who determines exemptions to a strict anti-hacking law called the Digital Millennium Copyright Act (DMCA), decided that unlocking mobile phones would no longer be allowed. But the librarian provided a 90-day window during which people could still buy a phone and unlock it. That window closes on Jan. 26.
Cellphone Unlocking In The U.S.A. Becomes Illegal From January 26 [mashable.com]
The new rule against unlocking phones won't be a problem for everybody, though. For example, Verizon's iPhone 5 comes out of the box already unlocked, and AT&T will unlock a phone once it is out of contract.
You can also pay full-price for a phone, not the discounted price that comes with a two-year service contract, to receive the device unlocked from the get-go. Apple sells an unlocked iPhone 5 starting at $649, and Google sells its Nexus 4 unlocked for $300.