The talk among real estate pros at water coolers and coffee shops across Chicago today is about McDonald's and its ongoing flirtations with a move from its longtime Oak Brook campus to Chicago. Only this time, all that's left is for McDonald's to put pen to paper.

The Golden Arches is close to sealing a deal with Sterling Bay to move its HQ to the former Harpo Studios campus in the West Loop, which Sterling Bay purchased for $32M last year. McDonald's would occupy 300k SF in a new building Sterling Bay has planned for the campus, Crain's reports.

McDonald's has been here before. The company was in the final stages of signing a 350k SF lease at Prudential Plaza last year, before having second thoughts. Earlier this year, Willis Tower was believed to be on the company's radar. The move would be another coup for the West Loop and Fulton Market office sector, which is already Chicago's hottest tech submarket, plus the irony of a fast food giant with a "billions and billions served" business philosophy calling Chicago's most popular restaurant district home is too rich to ignore.

The pending move would leave a major void, and new opportunities, in the Oak Brook office market, which is one of the strongest suburban office markets in the area thanks to its easy access to expressways and suburban rail. McDonald's current HQ, which CEO Steve Easterbrook says is becoming more expensive to maintain, would make for the highest-profile redevelopment since Motorola Mobility vacated its Libertyville campus for Merchandise Mart. [Crain's]