Major carriers in the US compete against each other by offering huge discounts on handsets and at times even providing them for free of cost, but in exchange they lock down the handset to their carrier and expect their customers to sign a contract for a period of 2 years. But the recent rule set by the Library of Congress makes cell phone unlocking illegal even after the 2 year contract period if it is done by the users directly and not by the carriers. A recent bill proposed by the Senators of various states against the ban on cell phone unlocking has been supported by many small carriers in the US and the association of small carriers. It is generally very difficult for small carriers to offer wide range of smartphones on their networks to attract new customers but with a bill that makes cell phone unlocking legal again they aim to attract new customers on to their networks.
The small carriers association says that locking down a cell phone to a particular carrier even after contract period basically restricts the choices a customer has. Many location in the US have fairly poor cellular service where small carriers try to capture the customers with much better service but the only problem seems to be with lack of good range of cell phone options that they provide.
With the successful 100000 signatures that the petition filed on the White House website, support from the Obama government and many other Senators fighting for cell phone unlocking we might soon witness some good news by the courts in the US ruling against the Library of Congress and unjustified use of DMCA.