Topps Co. said Monday that it has postponed a shareholder vote on a proposed $385 million buyout from a group led by former Walt Disney Co. Chief Executive Michael Eisner.

The New York-based sports card and bubble gum maker said the move is an effort to give investors more time to consider the offer. The Topps vote on the purchase was moved to Sept. 19 so stockholders “can evaluate recent developments,” Topps said in a statement.

The bid from Eisner’s Beverly Hills-based Tornante Co. and Chicago-based Madison Dearborn Partners LLC “would likely not receive the support” of most investors if the meeting were held as originally planned on Aug. 30, Topps said.

The sale to Eisner and his Madison was agreed to by a majority Topps’ board in June, but several investors, including two board members, opposed the deal, saying it undervalued the company.

Rival card maker Upper Deck Inc. made a $416-million offer in August. Topps’ board quickly expressed concerns over the Carlsbad-based baseball card maker being able to acquire adequate financing as well as clear regulatory hurdles. Upper Deck dropped its bid last week.