By the RBI definition a PIO (Person of Indian Origin) means an individual (not being a citizen of Pakistan or Bangladesh or Sri Lanka or Afghanistan or China or Iran or Nepal or Bhutan) who
(i) at any time, held an Indian Passport or (ii) who or either of whose father or mother or whose grandfather or grandmother was a citizen of India by virtue of the Constitution of India or the Citizenship Act, 1955 (57 of 1955); or (c) the person is a spouse of an Indian citizen or a person referred to in sub-clause (a) or (b).