Three investors that owned the privately held forerunner of Lake Forest-based Del Taco Restaurants Inc. will sell up to 3.87 million shares in a secondary offering, the fast food chain said.

Affiliates of Goldman Sachs Mezzanine Partners, Charlesbank Capital Partners and Leonard Green & Partners now hold about 9.3% of the company and would, if all 3.87 million shares are sold, end their investment in the chain.

The offering is being priced at $12 a share and is expected to close Friday, Oct. 30. The owners sold most of their stake in the prior company, Del Taco Holdings Inc., for about $155 million, during a two-step purchase of the chain by a “blank check” company called Levy Acquisition Corp. in Chicago.

Levy’s purchase concluded on June 30 and the Del Taco chain became a public company.

Del Taco has about 38.8 million shares outstanding, excluding about 16 million shares that are unvested, unissued, or exercisable in the future by outstanding warrants.

The chain has about 550 restaurants in 16 states.

Shares in Del Taco closed Monday down about 4% in midday trading to $12.26 and a $475 million market cap.