lockup option.A defense against a corporate takeover, in which a friendly party is entitled to buy parts of a corporation for a set price when a person or group acquires a certain percentage of the corporation’s shares. • An agreement of this kind may be illegal, to the extent it is not undertaken to serve the best interests of the shareholders. — Often shortened to lockup. [Cases: Corporations  312(5). C.J.S. Corporations §§ 500–501, 503, 524.]
[Blacks Law 8th]