The project, which would become the world's second tallest building at opening, was conceived and owned by Jerry Wolman in late 1964. The project was financed by John Hancock Mutual Life Insurance Company. Construction of the tower was interrupted in 1967 due to a flaw in an innovative engineering method used to pour concrete in stages, that was discovered when the building was 20 stories high. The engineers were getting the same soil settlements for the 20 stories that had been built as what they had expected for the "entire" 99 stories. This forced the owner to stop development until the engineering problem could be resolved, resulting in a credit crunch. The situation is similar to the one faced during the construction of 111 West Wacker, then known as the Waterview Tower. Wolman's bankruptcy resulted in John Hancock taking over the project, which retained the original design, architect, engineer, and main contractor.