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22 U.S. Code § 4414 - Requirements relating to the Endowment and its grantees

(a) Partisan politics
Funds may not be expended, either by the Endowment or by any of its grantees, to finance the campaigns of candidates for public office.
No funds granted by the Endowment may be used to finance activities of the Republican National Committee or the Democratic National Committee.
No grants may be made to any institute, foundation, or organization engaged in partisan activities on behalf of the Republican or Democratic National Committee, on behalf of any candidate for public office, or on behalf of any political party in the United States.
(b) Consultation with Department of State

The Endowment shall consult with the Department of State on any overseas program funded by the Endowment prior to the commencement of the activities of that program.