All Medicare providers who enrolled prior to March 25, 2011 will be required to re-validate their enrollment information. The preferred method of re-validation is through the Internet based PECOS system at
https://pecos.cms.hhs.gov but a paper application will also be accepted. Providers are instructed to complete the re-validation process
once they have been notified by their MAC (Medicare Administrative Contractor). MAC's will be sending out notices to providers between now and 2015. Failure to complete the re-validation process within 60 days after being contacted will result in deactivation of provider billing privileges.