This Act shall not apply to—
(i) any property succession to which is regulated by the Indian Succession Act (39 of 1925), by reason of the provisions contained in section 21 of the Special Marriage Act (43 of 1954);
(ii) any estate which descends to a single heir by the terms of any covenant or agreement entered into by the Ruler of any Indian State with the Government of India or by the terms of any enactment passed before the commencement of this Act;
(iii) the Valiamma Thampuran Kovilagam Estate and the Palace Fund administered by the Palace Administration Board by reason of the powers conferred by Proclamation (IX of 1124) dated 29th June, 1949, promulgated by the Maharaja of Cochin.
Legal Commentary & Landmark Judgments: Section 5
Section 5 specifies statutory exemptions where the provisions of the Hindu Succession Act do not apply, covering Special Marriage Act successions and historic impartible estates.
In estate planning involving inter-faith marriages under the Special Marriage Act, verify whether Section 5 r/w Section 21 SMA applies to displace HSA. If both parties are Hindus, Section 21A SMA saves the application of HSA.