Colwell Banker is a large real estate franchise owned by Realogy, which also owns Century 21 Real Estate and ERA Real Estate. The company was founded in 1906 in San Francisco after the 1906 San Francisco Earthquake by Colbert Coldwell as Tucker, Lynch, and Coldwell and is thus the oldest real estate company in the United States. In 1914 Benjamin Arthur Banker was invited to become a principal. In 1920 the company became Coldwell, Cornwell, and Banker. Bruce Cornwell resigned in 1940 and the company took its present name. The company expanded throughout, and in 1952 opened its first office outside California.