In October 1940, the Germans issued an ordinance defining who was a Jew according to the Nuremberg Race Laws. An ordinance from 10 January 1941 stated that anyone defined a Jew had to register. This also applied to all non-Jewish Dutch persons from the age of 15. Everyone was required to carry a personal identification card. Persons registered as Jews had a ‘J' stamped in their personal identification card, making them immediately recognisable during checks of personal details. Almost all the Jews in the Netherlands registered. Refusal meant a five year jail sentence. In total, 160,820 persons registered: 140,552 Jews, 14,549 half-Jews, and 5,719 quarter-Jews.