Little study has been made about land tenure in the Ayutthayan period of Thai history, except the pioneering work of Robert Lingat in which the French savant presented the classical view of Siamese king as the sole owner of whole land. This note attempts to review the thesis critically by re-examining the texts of the Three Seals Law used by Lingat and tries to show, within the limited knowledge obtainable from often vague passages of the Corpus, that the royal title on land is nominal and that there existed some kind of right on land on the part of common people.