EXHIBIT 21
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SUBSIDIARIES OF AMERICAN TOWER CORPORATION
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SUBSIDIARY JURISDICTION OF INCORPORATION OR
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ORGANIZATION
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American Tower Systems (Delaware), Inc. Delaware
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ATSC Operating Inc. Delaware
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ATSC LP Inc. Delaware
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ATSC Holding Inc. Delaware
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ATSC GP Inc. Delaware
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American Tower Systems, L.P. Delaware
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ATS Merger Corporation Delaware
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American Tower Rental Holding Corporation Delaware
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American Tower Rental, Inc. Delaware
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ATC Tower Corp. Delaware
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ATC-Prime I, L.L.C. Delaware
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ATC-Prime II, L.L.C. Delaware
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National Telecommunications Advisors, L.L.C. Massachusetts
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HHR, Inc. Kansas
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US Sitelease, Inc. Kansas
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Westark Towers, Incorporated Arkansas
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Gritz Tower Maintenance Company Texas
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ATS Needham, LLC* Delaware
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ATS/PCS, LLC* Delaware
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* ATS owns a 50.1% interest in this entity.
* ATS owns a 70.0% interest in this entity.
