A "large number" of social media comments and hundreds of phone calls protested the billboard on a major highway not far from O'Hare Airport, the firm said.
The Milbank international corporate law firm, which pledged $1 million over five years for student group events at the law school, withdrew its support after a Justice for Palestine event.
The event to honor women survivors, represented by the Jewish pro-Palestinian activist Hedy Epstein, was nixed "in consideration for the concerns against some of the participants."