Seems like once again we all have to stand up for what is users and buyers right to do what ever they want with their device. The exemption added to the DMCA by the US Copyright office in 2010 which fully legalized rooting, jailbreaking, unlocking and whatever else you do with your smartphone. This exemption will last for 3 years therefore must be renewed before expiring. Please do sign the petition to renew the exemtion. Cheers.
[Source: XDA Developers]