The Terrorist Identities Datamart Environment (TIDE) is the U.S. Government's central database on known or suspected international terrorists, and contains highly classified information provided by members of the Intelligence Community such as CIA, DIA, FBI, NSA, and many others.
There are about 745,000 names in TIDE. In 2008, more than 27,000 names were removed from the list when it was determined they no longer met the criteria for inclusion. According to the FBI, international terrorists include those persons who carry out terrorist activities under foreign direction. For this purpose, they may include U.S. persons (U.S. citizens and legal permanent residents). The Terrorist Identities Group (TIG), located in NCTC's Information Sharing & Knowledge Development Directorate (ISKD), is responsible for building and maintaining TIDE.