ADP said it gave personal data on tens of thousands of brokerage customers to someone who impersonated company officials. The information included names, addresses and the number of shares owned by individual investors, but did not include account numbers or Social Security numbers and would not allow unauthorized people to trade in the accounts. The security breach did, however, include confidential shareholder information for brokerage houses that ADP serves as part of its business, as well as information on an undisclosed number of public companies. Reportedly this breach covered investors with Fidelity Investments (125,000), Morgan Stanley (3,800) and UBS (10,000).