North American Free Trade Agreement, Article 1110
Article 1110: Expropriation and Compensation #
1 No Party may directly or indirectly nationalize or expropriate an investment of an investor of another Party in its territory or take a measure tantamount to nationalization or expropriation of such an investment (“expropriation”), except:
(a) for a public purpose;
(b) on a non-discriminatory basis;
(c) in accordance with due process of law and Article 1105(1); and
(d) on payment of compensation in accordance with paragraphs 2 through 6.