The family is paying about $800 million to acquire a 95% interest in the team, Wrigley Field and Tribune Co.'s 25% stake in Comcast SportsNet Chicago, which broadcasts many Cubs games on cable television.
Tribune will retain a 5% ownership stake in the joint venture.
The announcement is somewhat anticlimactic because in January Tribune had selected the Ricketts family as the winner of a protracted auction for the franchise. There were nine other prospective buyers.
But negotiations took much longer than anyone expected to seal the deal. Ultimately, though, Tribune came to terms with the Ricketts family.
Joe Ricketts hails from Omaha, but three of his four children live in the Chicago area. One of his sons, Tom Ricketts, an investment banker, led the family's pursuit of the team and is a die-hard Cubs fan.
The transaction would represent a return to family ownership for the team known as lovable losers because the Cubs last won the World Series in 1908. Before Tribune bought the team in 1981, the Wrigley family, founders of the chewing-gum company, owned the team for 65 years.
The Cubs have a national following because the games have been broadcast for years on Tribune Co.'s WGN cable superstation.
Tribune, which owns The Times, has been in Chapter 11 bankruptcy since December, and a major disposition of assets requires the court's blessing. As part of the court's approval process, Tribune said it will place the Cubs in Chapter 11 bankruptcy so that the franchise can "emerge free and clear" of the company's financial obligations.
The company said that the Cubs' bankruptcy will not interrupt team operations.
Court approval is expected because Tribune kept creditors informed throughout the sale. Major League Baseball owners also have to approve the deal.