A memorial service was held Thursday at Citizens Bank Park.
David's wife, Lyn Montgomery, attended Thursday's ceremony, along with a large group of former Phillies, including Jim Thome, Ryan Howard and Charlie Manuel.
Montgomery worked his way up from ticket salesman to the organization's chairman.
He put together a team that would go on to win the 2008 World Series.
Montgomery died last month following a 5-year battle with cancer.
He was 72-years-old.