have also adopted other restrictions on whom one can marry, such as prohibitions of marrying persons with the same surname, or persons with the same sacred animal. Anthropologists refer to these sorts of restrictions as exogamy. One example is South Korea's general taboo against a man marrying a woman with the same family name. The most common surname in South Korea is Kim (almost 20%); however, there are several branches (or clans) in the Kim surname. (Korean family names are divided into one or more clans.) Only intra-clan marriages are prohibited, as they are considered one type of endogamy. Thus, many "Kim-Kim" couples can be found. Societies have also at times required marriage from within a certain group. Anthropologists refer to these restrictions as endogamy. An example of such restrictions would be a requirement to marry someone from the same tribe. Racist laws adopted by some societies in the past—such as Nazi-era Germany, apartheid-era South Africa, and most of the United States in the nineteenth and the first half of the 20th century—and which prohibited marriage between persons of different races could also be considered examples of endogamy. In modern Israel, the status of marriage is the same as it was historically under the Ottoman Empire and the British mandate, where civil marriage does not exist and authority for marriage is given by the state solely to the recognized religious denominations (Orthodox Judaism, Islam, Druze, and ten Christian denominations (primarily Orthodox Christianity and Catholicism, but also including the Episcopal Church). Israeli couples who wish to contract a marriage that are not allowed under the auspices of any of these religious denominations (including same-sex marriages, marriages involving Israelis of Jewish descent who are not recognized by the state as Jewish and marriages between non-Jewish Arab citizens of Israel and Israeli Jews) or simply wish to get legally married outside the auspices of one of these institutions cannot do so in Israel itself. However, Israel does recognize civil marriages between Israeli citizens that are contracted abroad, including same-sex marriage, so couples in these situations will often hold a non-binding ceremony in Israel and fly abroad (often to nearby Cyprus) to contract a legal marriage that is then recognized in Israel. In the U.S., many laws banning interracial marriage, which were state laws, were gradually repealed between 1948 and 1967. The U.S. Supreme Court declared all such laws unconstitutional in the case of