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16 U.S. Code § 4223 - Prohibited acts

Except as provided in section 4222(e) of this title, it is unlawful for any person—
to import raw ivory from any country other than an ivory producing country;
to export raw ivory from the United States;
to import raw or worked ivory that was exported from an ivory producing country in violation of that country’s laws or of the CITES Ivory Control System;
to import worked ivory, other than personal effects, from any country unless that country has certified that such ivory was derived from legal sources; or
to import raw or worked ivory from a country for which a moratorium is in effect under section 4222 of this title.