This excerpt taken from the WDC DEF 14A filed Sep 24, 2007.
In certain cases, the Compensation Committee may approve the payment of a sign-on bonus in connection with the hiring of a key executive. The Compensation Committee approves these bonuses in circumstances in which it believes they are necessary to attract and motivate a potential key hire to accept employment with us, especially in light of other compensation the individual may relinquish by accepting employment with us. In April 2007, the Compensation Committee approved a sign-on bonus of $75,000 for Mr. Leyden in connection with the commencement of his employment with us. Mr. Leyden is required to repay this sign-on bonus in the event he voluntarily terminates his employment with us prior to being employed for twelve full months.