IMC is quietly turning Willis Tower into its Midwest command center. The Amsterdam-based trading firm is expanding its Chicago footprint again with a fresh block of office space at the city's most famous skyscraper. It is the firm's second significant expansion inside the Loop high-rise in less than four years, a reminder that some fast-growing finance and trading shops still want a serious downtown hub. The move keeps IMC among the building's largest tenants and extends a recent streak of leasing wins at the tower.
According to CoStar, which reported the deal on February 3, 2026, the Dutch firm is adding a large block of space at Willis Tower, and the outlet describes it as IMC's second sizable expansion there in under four years. CoStar lists brokerage and leasing contacts tied to the transaction but keeps many of the deal specifics behind its subscriber paywall. Its item is the first public notice of this latest expansion.
IMC's own materials show the firm has been deeply rooted in the building for years. The company lists its Chicago operation at Willis Tower and says the office now hosts more than 650 employees, which helps explain why the firm keeps enlarging its footprint. According to IMC, the Loop office serves as a major North American base for its market-making and trading technology teams, reinforcing the logic of doubling down on the same location.
Why Willis Tower Keeps Landing Big Tenants
The latest expansion comes after the building's owner poured hundreds of millions of dollars into repositioning the property, reworking space and amenities to woo new and growing tenants. Building Design + Construction detailed a roughly $500 million modernization that reconfigured hundreds of thousands of square feet into tenant amenities and added new retail at the tower's base. IMC's earlier move, a 2022 expansion that increased its space by about 50 percent to roughly 160,000 rentable square feet, already made the firm a major player in the building's recovery, according to REjournals.
That leasing momentum matters as Blackstone and EQ Office weigh strategic options for Willis Tower in the middle of a complicated financing picture. Local coverage has indicated that the owner is quietly testing investor interest while pointing to recent leasing wins. Blackstone eyes Willis Tower exit and has been highlighting fresh tenant commitments as part of its case for the asset. Another expansion by a tech-driven market maker gives the landlord more evidence that premium, amenity-heavy office space downtown can still draw demand.
Full lease size and term for IMC's newest addition had not been disclosed publicly at the time of reporting, and CoStar remains the first published source on the deal. As filings and property reports surface, more precise figures and broker credits are likely to emerge. For now, the expansion stands as another vote of confidence in a renovated Willis Tower from one of its most important tenants.
