The shadow of the John Hancock Building can be seen in this snapshot of the Signature Room, taken from the 96th-floor lounge. View Full Caption Flickr/vxla

MAGNIFICENT MILE — The owner of the Signature Room & Lounge atop the John Hancock Center has sued its landlord, alleging changes to the tower's lobby have cost the penthouse bar more than $1 million in lost business.

In the complaint filed late Thursday in Cook County Circuit Court, Infusion Management Group said a temporary wall erected in the Michigan Avenue tower's ground-floor lobby has denied Signature Room patrons direct access to the 95th-floor bar's elevators, congesting the lobby to the point where the wall is a customer deterrent.

"It's just like at Great America. You walk up and see a long line, you go to the next ride," said lawyer Brian Garelli, who represents Infusion Management Group.

Infusion estimates it has lost at least $1 million in potential business due to the wall, which was installed in December 2013.

Dave Matthews explains why the Signature Room feels the door repels potential patrons:

Infusion leases the 95th and 96th floors of the Hancock Center, 875. N. Michigan Ave., which was sold to a group of investors for $410 million in 2013. The new owners, including Chicago-based Hearn Co., plan extensive renovations to the tower, and erected the temporary wall as part of a plan to eventually separate the office and retail components of the tower, according to the complaint.

Yet Hearn has not told the Signature Lounge when those renovations will occur, and has refused to take down the temporary wall or negotiate a settlement, Garelli said. The Signature Room recently exercised a five-year lease extension for its space, he said.

"The building's current owners have taken steps that seem to serve no purpose other than to hurt the businesses that have been in this building for decades," Infusion CEO Richard Roman said.

Hearn President and CEO Stephen G. Hearn declined to comment through a company representative. A spokesman for another defendant, Prudential Real Estate Investors, which owns the Signature Lounge, also declined to comment.

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