Litchfield Cavo, a law firm specializing in civil litigations for the insurance industry, renewed its lease by expanding 12,231 square feet on the fourth floor of 303 W. Madison St. in Chicago. With two years left on the previous lease, the firm extended for an additional eight years and four months. Litchfield Cavo currently occupies the second and third floors, totaling 34,993 square feet, making it the largest tenant in the building.