The Seventh Schedule of the Constitution of India demarcates legislative powers between the Union and State governments. Entry 21 of the Union List (List I) specifically empowers the Union government to legislate on 'Inter-state quarantine, that is to say, the administration of plague requirements of ports and airports outside such ports and airports'. Conversely, inter-state trade and commerce falls under Entry 42 of the Concurrent List, and corporation tax is exclusively a Union subject under Entry 85 of the Union List, while migration is generally a state subject under Entry 17 of the State List.