Terms of the 10-year deal will give Winston & Strawn 50,000 sf of office space at MaguirePartners' 333. S. Grand office complex, commonly called Wells Fargo Center I. Though brokers involved in the transaction won't discuss financial terms, other sources tell GlobeSt.com that the pact is worth about $15 million.

The new lease more than doubles the 21,000 sf the firm has occupied at nearby 444 S. Flower. Winston & Strawn was represented by Nancy Packer of Chicago-based advisory firm U.S. Equities and by local Cushman & Wakefield broker Tom McDonald. An in-house MaguirePartners team led by Tony Morales represented the owner.

Though Downtown's vacancy factor still hovers around 20%, it has steadily been dropping as tenants are drawn to the area's relatively inexpensive space. Some major sales have also recently taken place, and others are expected to soon be announced.