Original: The twelve U.S. trials are collectively known as the "Subsequent Nuremberg Trials" or, more formally, as the "Trials of War Criminals before the Nuremberg Military Tribunals" (NMT).
Simplified: These twelve trials are known as the "Subsequent Nuremberg Trials" or, more formally, as the "Trials of War Criminals before the Nuremberg Military Tribunals" (NMT).