The $3.1 billion Oklahoma Public Employees Retirement System, Oklahoma City, selected Bankers Trust as its new master custodian and securities lending agent. Bankers replaces Northern Trust, which was among the three finalists. The other finalist was Bank of New York. Steve Edmonds, executive director, said Bankers was hired based on its overall technological capabilities, which fit best with the fund's requirements. The state requires contracts to be rebid at the end of each five-year contract period.