Keystone Property Group has tapped Richard S. Gottlieb to serve a president and chief operating after serving in management roles for the company over the last 12 years. Gottlieb will oversee all operations, development, management and leasing of the firm’s multi-million square foot portfolio. Prior to his time at Keystone, Gottlieb served as a senior vice president at Stoltz Management Co. and also served in various capacities with Prentiss Properties Trust and Pennsylvania Real Estate Investment Trust. Keystone has properties in Pennsylvania, New York, New Jersey and Connecticut.