law: Constitution of India, 1949 
    7. Rights of citizenship of certain migrants
  
  to Pakistan – 
  Notwithstanding anything in Articles 5 and 6,
  
  a person who has after the first day of March, 1947,migrated from the territory
  
  of India to the territory now included in Pakistan shall not be deemed to be a
  
  citizen of India:
  Provided  that nothing in this article shall
  
  apply to a person who, after having so migrated to the territory now included
  
  in Pakistan, has returned to the territory of India under a permit for
  
  resettlement or permanent return issued by or under the authority of any law
  
  and every such person shall for the purposes of clause (b) of Article 6 be
  
  deemed to have migrated to the territory of India after the nineteenth day of
  
  July, 1948.