=Potbelly (PBPB) CEO leaving sandwich chain after nine years at helm

Aylwin Lewis, the CEO of the Potbelly sandwich chain, will part ways with the company in August.

The Chicago-based restaurant did not provide a reason behind the exit.

Lewis, 63, who serves as both CEO and chairman, joined the company in 2008 and led the chain through an expansion and IPO.

"We are grateful for Aylwin's leadership during his nine-year tenure at Potbelly. He is a world class restaurant leader and Potbelly benefited from his leadership," Peter Bassi, a Potbelly board member, said in a statement on Tuesday. “We have started the search process for a new CEO."