According to the Visa Department of the Consular Section of the Embassy of the United States in Ottawa, as communicated to the IRBDC by telephone on 11 April 1990, I-509 is the code name for an application for permanent residence in the United States for persons holding type A or G occupations within the United States. That is, foreigners working in the U.S. for foreign diplomatic representations or international organizations such as, for example, the United Nations. For an I-509 application to be fully processed the applicant will be required to sign a waiver for his/her diplomatic immunity. If this is not done, the diplomatic immunity will be suspended by the authorities before the person is granted permanent residence. The stamp saying "I-509 filed Nov 16 1988" would indicate the I-509 application was filed on November 16, 1988.

The same source added that I-589 is the code name of an application for asylum.