Rocket Hit With Investor Lawsuit Over Insider Trading Suspicions

An investor in Rocket Cos., corporate parent of Rocket Mortgage and Quicken Loans, sued the company in Delaware, seeking to investigate claims that its controlling stockholder, Cleveland Cavaliers owner Dan Gilbert, sold $500 million worth of stock based on inside information.

The lawsuit, filed late Thursday in Delaware Chancery Court, accuses Gilbert’s holding company, Rock Holding Inc., of dumping more than 20 million shares in late March, two days before the end of a fiscal quarter that saw the lender perform “well below” market expectations.

The move came while Rocket downplayed concerns about contracting sales margins and a price war ...