An affiliate of Santa Ana’s First American Corp. said Wednesday it reached an agreement to buy the title company’s credit information unit for $570 million in an all stock deal.

St. Petersburg, Fla.-based First Advantage Corp. said the deal is valued at $20.50 per share.

First American, the largest shareholder in First Advantage, announced the deal in March at a price of $550 million.

First American and another of its affiliates, First American Real Estate Solutions, are selling their mortgage, automotive, consumer and subprime credit businesses to First Advantage in exchange for 28 million shares of First Advantage class B common stock. When the sale closes, First American will own nearly 80 percent of First Advantage, up from 67 percent now.

First Advantage was formed two years ago when First American combined a unit with US Search.com Inc. The company provides employment background checks, substance abuse testing, resident screening, automobile record reporting and investigative services to corporate customers.

*Mathew Padilla of the Orange County Business Journal contributed to this story.