E-Trading Firm Locks in Chicago West Loop Office Lease

Hines and La Caisse’s 10 South Riverside may have landed its next big fish.

Interactive Brokers Group is closing in on a lease at 10 South Riverside Plaza, seeking to consolidate its Chicago offices after a previous deal fell apart in late-stage negotiations, Crain’s reported.

The electronic trading firm is in advanced talks to lease roughly 60,000 square feet at the tower, which recently underwent a $75 million renovation. If finalized, the move would combine Interactive Brokers’ current offices — 60,000 square feet at 209 South LaSalle and a 40,000-square-foot sublease at 300 South Riverside — into a single West Loop location ahead of its lease expirations next year.

CBRE is representing both sides in the deal, with Mark Cassata and Bill Sheehy repping the tenant and Kelsey Scheive and Kelsey Morgan handling leasing for La Caisse.

The pivot comes after a failed lease at 300 South Riverside, where the company had been negotiating for a 53,000-square-foot space before talks collapsed.

That building’s financial distress may have played a role. The land beneath 300 South Riverside is owned separately, and the ground lease holder, World Wide Group, recently missed a payment deadline on a $167 million mortgage tied to the parcel, according to CoStar. The building’s owner, Third Millennium Group, also holds a $175 million loan from Shinhan Bank on the tower itself.

Such capital stack complexity has become increasingly common as building owners navigate devalued assets, tight credit and expensive tenant build-outs in the post-pandemic market. In some cases, like R.M. Chin’s cancelling a lease at 801 South Canal, landlords have failed to deliver promised tenant improvement allowances or have even floated converting office buildings to data centers.

The pending lease at 10 South Riverside offers a win for its owners, who are trying to backfill space at a time when the building is only 65 percent leased, well below the downtown average.

Landing a publicly traded tenant like Interactive Brokers, which reported nearly $5.2 billion in 2024 revenue, would validate the recent renovation and stabilize occupancy in what’s been a challenging office leasing environment.

— Judah Duke