Important Additional Information Will be Filed with the SEC In connection with the proposed transaction, American Tower plans to file with the SEC a Registration Statement on Form S-4 containing a Joint Proxy Statement/Prospectus. INVESTORS AND SECURITY HOLDERS OF AMERICAN TOWER AND SPECTRASITE ARE URGED TO READ THE REGISTRATION STATEMENT AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, INCLUDING THE JOINT PROXY STATEMENT/PROSPECTUS THAT WILL BE PART OF THE REGISTRATION STATEMENT WHEN THEY ARE AVAILABLE, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT AMERICAN TOWER, SPECTRASITE, THE PROPOSED TRANSACTION AND RELATED MATTERS. The final Joint Proxy Statement/Prospectus will be mailed to shareholders of American Tower and SpectraSite. Investors and security holders of American Tower and SpectraSite will be able to obtain copies of the Registration Statement and the Joint Proxy Statement/Prospectus, when they become available, as well as other filings with the SEC that will be incorporated by reference into such documents, containing information about American Tower and SpectraSite, without charge, at the SEC's website http://www.sec.gov. These documents may also be obtained for free from American Tower by directing a request to American Tower Corporation, Investor Relations, 116 Huntington Ave, Boston, MA 02116 or for free from SpectraSite by directing a request to SpectraSite at SpectraSite, Inc., 400 Regency Forest Drive, Cary, NC 27511, Attention: Secretary. Participants in Solicitation American Tower, SpectraSite and their respective directors and executive officers and other members of management and employees may be deemed to be participants in the solicitation of proxies from American Tower and SpectraSite shareholders in respect of the proposed transaction. Information regarding American Tower's participants is available in American Tower's Annual Report on Form 10-K for the year ended December 31, 2004, and the proxy statement, dated April 27, 2005, for its 2005 annual meeting of stockholders, which are filed with the SEC. Information regarding SpectraSite's participants is available in SpectraSite's Annual Report on Form 10-K for the year ended December 31, 2004 and the proxy statement, dated March 31, 2005, for its 2005 annual meeting of shareholders, which are filed with the SEC. Additional information regarding the interests of such participants will be included in the Registration Statement containing the Joint Proxy Statement/Prospectus to be filed with the SEC. |