Double-Trigger Acceleration is a provision in a contract that allows for the acceleration of vesting of stock options or other equity-based compensation in the event of certain specified events. This type of acceleration typically occurs when there are two trigger events, such as a change in control of the company followed by the termination of the employee's employment.
For example, let's say an employee has stock options that vest over a period of four years. Under the terms of the employee's contract, the vesting of the options will accelerate if there is a change in control of the company and the employee is terminated within a certain period of time after the change in control.
In this case, the employee would be entitled to vest all of their remaining options immediately, rather than waiting for them to vest over the remaining vesting period. Double-Trigger Acceleration is often included in contracts to provide employees with additional protection in the event of a corporate change that could negatively impact their employment.