CHICAGO—Back in April 2012, when GlenStar Properties, LLC and the USAA Real Estate Co. purchased the Chicago Board of Trade building for $151 million, the new owners set a goal of transforming the 84-year-old landmark into a true player in the downtown office market. At the time, the 1.3-million-square-foot building at 141 W. Jackson was only 61% occupied, with most of the space occupied by trading firms, many of which had been there for decades.

The partners' first step was to preserve this existing tenant base, and they successfully renewed 123 leases, which accounted for a total of about 250,000-square-feet. But in the last six months, they also finished $25 million in capital improvements and brought in a host of new tenants that include software, engineering, public relations, investment and data center firms.

“To be successful, you need to be as attractive to as many people as possible,” Christian Domin, GlenStar's managing director, tells GlobeSt.com. The occupancy rate has hit about 70%, and within a little more than a year, the partners expect to have a stable property that will attract interest from the deep-pocketed investors currently hunting for acquisitions in the CBD's vibrant office market. “You just can't do that with one industry.”