According to a Chicago Sun-Times report that cited a baseball source, there was "zero chance" of Cuban taking over the Cubs.
The Sun-Times source said the Internet billionaire would meet with resistance in trying to get approval from Major League Baseball.
Cuban wouldn't comment on the report before the Mavericks played Denver on Friday night.
"There's no reason to comment on anonymous comments from unsolicited sources. I mean it's ridiculous," Cuban said.
Cuban is in the running to purchase the team from the Tribune Co. after reportedly bidding more than $1 billion.
Others believed to be interested are a group headed by John Canning, chairman of private equity firm Madison Dearborn Partners LLC; and the family of online brokerage Ameritrade founder Joe Ricketts.
"Nothing's changed," Cuban said. "I mean it's a great opportunity."