Exhibit 99
December 29, 2000
This will confirm the agreement by and between the undersigned that the
Schedule 13D filed on or about this date, and any amendments thereto, with
respect to the beneficial ownership of the undersigned of shares of the Class A
Common Stock of TeleCorp PCS, Inc. is being filed on behalf of each of the
undersigned. This agreement may be executed in two or more counterparts, each of
which shall be deemed an original, but all of which together shall constitute
one and the same instrument.
/s/ Thomas H. Sullivan
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Thomas H. Sullivan
/s/ Gerald T. Vento
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Gerald T. Vento
