Interthink Inc., an Agoura Hills mortgage services company, has been acquired for $155 million by First American Financial Corp., a provider of real estate transaction services based in Santa Ana, the company announced Thursday.

Interthinx will beef up First American’s services providing fraud prevention, identity and income validation, and collateral adequacy on home mortgages.

First American Chief Executive Dennis Gilmore said the acquisition was prompted by market and regulatory changes that have stiffened mortgage-origination requirements.

“Our customers have expressed to us a desire for tighter integration between loan origination activities, loan quality verification processes, and title and settlement services,” said Gilmore, in a prepared statement.

The deal between Interthinx and First American is expected to close by March 31.