Arthur J. Gallagher & Co. (AJG) recently acquired Cornerstone Commercial & Personal Insurance Services, Inc. The terms of the transaction have not been revealed yet. Rancho Cucamonga, CA-based Cornerstone is a retail insurance agency that serves commercial and personal clients. It caters to its services across San Bernardino and Riverside counties. The company remains focused on commercial real estate, construction and homeowners associations. With this acquisition, AJG will leverage the expertise of Corner ...