This excerpt taken from the CCO DEF 14A filed Apr 7, 2008.
Stockholders interested in submitting a proposal for inclusion in the proxy materials for the annual meeting of stockholders in 2009 may do so by following the procedures prescribed in SEC Rule 14a-8. To be eligible for inclusion, stockholder proposals must be received by the Secretary of Clear Channel Outdoor no later than December 8, 2008. Proposals should be sent to Secretary, Clear Channel Outdoor Holdings, Inc., P.O. Box 659512, San Antonio, Texas 78265-9512.