Foothill Ranch-based mortgage lender loanDepot Inc. has filed for an initial public offering with the Securities and Exchange Commission.

The number of shares of its common stock and the price range for the proposed offering have not been determined.

LoanDepot was founded in 2010 by Anthony Hsieh and is among the biggest nonbank mortgage lenders in the U.S.

The company has about 4,000 employees, including more than 1,000 in its Orange County operations. It has about 130 branches nationwide.

LoanDepot had $13.2 billion in loan volume last year and $8.4 billion in 2013. It has told the Business Journal that its estimated loan volume for 2015 is between $23 billion and $25 billion.

It recently doubled its OC office space to more than 238,000 square feet.