Section 453 — Sale — definition
Statutory text (Thai original)
อันว่าซื้อขายนั้น คือสัญญาซึ่งบุคคลฝ่ายหนึ่ง เรียกว่าผู้ขาย โอนกรรมสิทธิ์แห่งทรัพย์สินให้แก่บุคคลอีกฝ่ายหนึ่ง เรียกว่าผู้ซื้อ และผู้ซื้อตกลงว่าจะใช้ราคาทรัพย์สินนั้นให้แก่ผู้ขาย
Verbatim from the Royal Gazette / Office of the Council of State
English translation
Sale is a contract whereby a person, called the seller, transfers to another person, called the buyer, the ownership of property, and the buyer agrees to pay to the seller a price for it.
This English translation is provided for reference only and has not yet been firm-verified — always rely on the Thai original.
Firm annotation
Section 453 is the master definition of every sale transaction in Thailand. Three requirements: (a) the seller has and transfers ownership; (b) the price is in money (not barter — that's §518 exchange); (c) there is consensual agreement. For immovables and certain movables (cars, ships, condos), additional formalities apply — see §456 (registered writing for land).