The John Buck Co. is also a minority owner, as well as manager and leasing agent for the building. The property is expected to sell for up to $160 million, sources say.

The building is being sold with an existing mortgage, says Jaime Fink, managing director with Holliday Fenoglio Fowler LP. "It is a core asset with attractive (and) assumable financing," he says. Fink said that he could not disclose the interest rate.

Fink, Jeff Bramson and Ken Glomb, all with Holliday Fenoglio Fowler, are marketing the building, which is in Chicago's River North neighborhood. The 29-story building was constructed in 1990 at the corner of State Street and Grand Avenue. The building is 94% leased. Major tenants include the American Medical Association and the Accredited Council for Graduate Medical Education, which signed a lease in late 2006 for two full floors. The building has an average lease term of eight years.