to place of birth and to parentage” which “are recorded through birth registration” (UN 2011, 6). For this reason, birth registration can be “crucial” to “realising the right to a nationality” (ibid.). In some cases, states do not deny nationality by force of law, but certain populations cannot register the birth of their children, which denies these children proof of nationality and its rights and entitlements. In other cases, as with members of Hill Tribes in northern Thailand, local officials refuse to register childbirths (Rijken et al. 2015). The United Nations Children’s Fund (UNICEF), which maintains a global database on birth registration (UNICEF 2017), reports lower than average rates of registration in some developing countries, for certain ethnic and religious minorities, in remote and rural areas, and for children from poor households and with uneducated mothers (UNICEF 2013). Some unregistered migrants may find themselves “doubly undocumented”; that is, without identity documents indicating their nationality in their home state or in their current state of residence. Exacerbating this problem, some countries also make it difficult to register births abroad by requiring a return visit, exorbitant fees, or registration within a short window of time (UNHCR and OSJI 2012; Price 2013). Similarly, some persons lack the documentation to prove their place of birth. This may occur due to weak civil registry systems, lack of access to government offices and services, extreme poverty, or rapid flight (Price 2013). Children born to refugees or asylum seekers may not be able to secure identity documents and to prove their nationality if they cannot return to their countries of origin or contact the government because they fear persecution (ibid.). The 1961 Convention on the Reduction of Statelessness requires Contracting States to prevent and reduce statelessness by addressing several of these situations. However, these problems persist in the United States, which for the reasons explained below, is home to stateless persons in most, if not all of these categories. Generous US citizenship policies—anchored by the Fourteenth Amendment of the US Constitution’s guarantee of citizenship to “All persons born or naturalized in the United States, and subject to the jurisdiction thereof”—operate as a strong check against statelessness for those born in the United States. For this reason, this report primarily covers US residents who migrated to the United States and are potentially stateless or potentially at risk of statelessness. As discussed, these persons have not yet become naturalized US citizens, whether due to the lack of an available legal avenue, the inability to meet the requirements for permanent residence or citizenship, extended processing delays or backlogs, or for other reasons. Some US residents may have lost their nationality while living in the United States. The US Refugee Act of 198022 sought to harmonize US law with the international standards for refugee protection set forth in the 1951 United Nations Convention Relating to the Status of Refugees and the 1967 Protocol Relating to the Status of Refugees.23 However, the United States has not ratified the 1954 Convention or the 1961 Convention, and it lacks a designated legal framework on statelessness (Baluarte 2015; Corgan 2012), including a facilitated path to citizenship. Stateless persons in the United States must instead meet the requirements of US immigration and naturalization law to secure nationality. Although generous in some respects, US 22 Refugee Act of 1980, Pub. L. No. 96-212, 94 Stat. 102 (1980). 23 Convention Relating to the Status of Refugees, July 28, 1951, 189 UNTS 150 (entered into force April 22, 1954); Protocol Relating to the Status of Refugees, January 31, 1967, 606 UNTS 267 (entered into force October 4, 1967). 11