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In land law, an option to purchase is a contractual arrangement by which the seller gives the prospective buyer a right to buy within a particular time. To be valid, an option must be supported by consideration, but the consideration may be nominal. An option is a type of estate contract and in order for it to bind a subsequent purchaser, it should be protected by an entry on the charges register against the registered title (if registered) or a class C(iv) land charge if not.