- Under 1332(c) a corporation shall be deemed to be a citizens of every state and foreign state by which it has been incorporated and of the state or foreign state where it has its principal place of business - Can be a citizen of more than one state (state of incorporation and state where it has its principal place of business -- only one state for PPB) - Hertz defined 'principal place of business' as the corporation's nerve center -- where the corporation's officers direct, control, and coordinate the corporation's activities