SAN FRANCISCO (MarketWatch) -- United Technologies Corp. utx said Monday it withdrew its offer for Diebold Inc. DBD, +2.41% . In February, United Technologies offered $40-a-share for Diebold, which Diebold rebuffed in March. "We had hoped we could negotiate a transaction that would have created substantial value for both your and our shareholders," said United Technologies Chairman George David in a letter to Diebold Chairman John Lauer. "It's unfortunate this won't happen." Shares of Diebold rose 6.2% to $30.03, and shares of United Technologies rose 9.5% to $52.15 in recent trading.