Bankmail
  
Think: Blackmail...only for bank acquisitions. It has nothing to do with what the union postal worker delivers to your door each day.
Big Bucks Bank buys out Little Bucks Bank. To protect the deal and prevent Little Bucks from financing the bid of any other potential acquirer, Big Bucks has Little Bucks sign a Bankmail agreement. Now, Little Bucks has guaranteed they will only finance Big Bucks' bid, or no bid at all.