CopperPoint Mutual Insurance Co. on Wednesday announced its acquisition of Pacific Compensation Insurance Co., a Thousand Oaks subsidiary of Alleghany Corp.

The Arizona-based insurance company said it acquired PacificComp, a worker’s compensation carrier, for $150 million in cash, which is less than it sold for 10 years ago. The acquisition will be CopperPoint’s first entrance to the California market.

PacificComp formerly operated under the name Employers Direct Insurance Co., which was established in 2002. In 2007, the company was acquired by Alleghany, a publicly traded insurance company based in New York, for $195 million. At the time, the company wrote workers compensation insurance for about 740 California businesses.

CopperPoint said the combined book of business for the two companies will be around $400 million in premiums.

“In joining CopperPoint we have found an ideal strategic and cultural fit for our employees, broker partners and policyholders that will allow us to continue our service to the market without interruption and provide us with the ability to expand the products and services we offer,” said Jan Frank, chief executive of PacificComp in a statement.

Shares of Alleghany (Y) closed up $2.89, or less than 1 percent, to $596.61 on the New York Stock Exchange.