The company was founded roughly 80 years ago by Samuel Lemberg, an important early donor to Brandeis University in Waltham. An academic building on campus is named for him. Current Midwood president John Usdan, Lemberg's grandson, is a Brandeis trustee.
Davis, the company executive, said Midwood normally keeps properties it develops, rather than selling them to investors, and plans to do the same with the Downtown Crossing development.
In addition, Davis said Midwood hopes to work with several existing tenants, including CitySports and the Bromfield Pen Shop, to accommodate them in the new building. The new building will have 60,000 square feet of retail space.
"There will be new tenants, and there will be relocation of tenants," Davis said.
The city said it will try to assist any stores that are forced to move.
Mike Kennedy, cofounder and chief executive of CitySports, said he wasn't surprised by the announcement, because he knew Midwood had acquired the buildings. He said CitySports has been in Downtown Crossing for about 15 years and plans to remain there for the long term - either in the new building or nearby.
"There's plenty of time to work it all out. If it doesn't work out for us" to stay, Kennedy said, "we'll find something else."
Other businesses located there could not be reached for comment.