http://en.wikipedia.org/wiki/National_Do_Not_Call_Registry
Exceptions to the do-not-call rule
Known exceptions
Placing one's number on the National Do Not Call Registry will stop most, but not all, unsolicited calls. The following are exceptions granted by existing laws and regulations.
* The registry only applies to residential lines, not to business lines.[4]
* A person may still receive calls from political organizations.
o The organization Citizens for Civil Discourse has lobbied Congress to close this loophole by developing a National Political Do Not Call Registry where voters can register their phone numbers and ask politicians to take the "Do Not Contact Pledge". Its database is not backed by the force of law and as of November 2008, only 3 politicians running for office signed the pledge.[5]
* A person may still receive calls from charities.
* A person may still receive calls from those conducting surveys.
* A person may still receive calls from companies with which he or she has an existing business relationship for up to 18 months after his or her last purchase, payment, or delivery from it, unless person specifically asks the company not to call again.
* A person may still receive calls from a company up to 31 days[6] after submitting an application or inquiry to that company, unless the company is specifically asked not to call.
* A person may still receive calls from bill collectors (either primary creditors or collection agencies). These callers are, however, regulated by other laws, such as those limiting them to calling during "reasonable hours." Some creditors may not call debtors who file for bankruptcy protection.
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Do-Not-Call Improvement Act of 2007
On February 15, 2008, U.S President George W. Bush signed into law the H.R Bill 3541: Do-Not-Call Improvement Act of 2007. Two major changes were enacted through this law:
* While originally required to renew their phone numbers every five years,
consumers need now only register once to maintain their phone numbers on the Do Not Call Registry.
* The frequency with which the FTC must purge the registry of disconnected and reassigned numbers has also been increased to several times a month. However, the Do-Not-Call Improvement Act prohibits removing numbers from the do-not-call registry unless the number is invalid, disconnected, or reassigned; or the individual to whom the number is assigned so requests.[11]