Film prexy defends practice of "block booking." Washington, D.C., April 6. Sidney R. Kent, President of the 20th Century Fox Film Corp., testifying before the Senate Interstate Commerce Subcommittee today, defended block booking of Motion Pictures as legitimate and traditional business practices. The producers right to sell their merchandise in their own way, Kent said, is sacred so long as they are "In free and open competition." 4-6-39