Through the new “10+2” rule, also known as the Importer Security Filing (ISF) program, U.S. Customs & Border Protection seeks to improve its knowledge about the content, origin and destination of international containers, and identify potential terrorist threats prior to departure from an overseas port. 10+2 requires importers or their agents to provide CBP with 10 data elements before a vessel departs the overseas port. Two additional data elements must be filed to the agency by the vessel operators.