Nothing has been approved yet, but the rooftop owners are worried more signs could hurt their business, which could end up hurting the Cubs and the City of Chicago.
With the Cubs out of town, crews are busy assembling the stage for concerts that will take over Wrigley Field this weekend.
From the rooftop over Murphy's Bleachers you can get a good look at the work and a good idea of how the view of the field could be blocked if the Cubs erected a Jumbotron or advertising signs above the outfield walls.
It would kill the rooftop business. That's why rooftop owners have been talking to the Cubs about their plans to try to increase revenue.
"We're concerned that we're going to be blocked out," said Beth Murphy.
To make their point rooftop owners are opening their books to ABC7 News.
They say the combined rooftop revenue has an economic impact that includes royalties to Cubs, $3.5 million, city and county state taxes, $2.9 million, and a payroll of $2.5 million for approximately 250 employees.
The Cubs and Mayor Rahm Emanuel have been negotiating a deal that could potentially relax Wrigley Field's landmark status to allow for more advertising.
It could also allow the Cubs to close Sheffield Avenue on game days for street festivals.
Coincidently, this stretch of Sheffield was closed Wednesday while crews work on the stage inside.
A spokesperson for Mayor Emanuel says the city will do what is in the best interest of taxpayers.
Alderman Tom Tunney said there is no deal is in place.
"I believe we can work together to find a compromise that will allow Wrigley Field to expand and improve while keeping an inviting and safe environment within our neighborhood that protects property values for homeowners," Tunney said.
Murphy hopes that is true.
"People have invested millions," she said. "We employ people. So you wouldn't want to eliminate the rooftops from the equation."
The Cubs have yet to reveal any changes they'd like to make at Wrigley Field. When we asked them for a response to concerns from rooftop owners, they declined.