Randall and Mr. Waternoose are the only villains of the film.
Not a third, and here's why
There have been several attempts to call Mr. Waternoose "Henry J. Waternoose III". This is based on him stating that the Monsters Inc. company had been in his family for three generations. However, for him to be HJW III, that would mean his father is Henry J. Waternoose, Jr. and his grandfather is Henry J. Waternoose, Sr.
Nowhere in the movie is Mr. Waternoose's father and grandfather named. His father could have been named Fred and his grandfather Barney for all we know.
A real-life example of a company that has been run by one family is the Ford Motor Company. It was founded by Henry Ford but was originally run by John S. Gray. After Gray left, Henry became the CEO until it was turned over to his son Edsel Ford. After Edsel's death, the company went back to Henry until it went to Edsel's son, whom Edsel had named Henry Ford II. After that Philip Caldwell was CEO until the time when Lee Iacocca was fired, and at that point, Philip also became the company president. Then you've got William Clay Ford Jr., who had been company president, CEO and COO until he turned those over to Alan Mulally and currently is executive chairman, but now the company president and CEO roles are held by Mark Fields.
So while the Ford Motor Company has been in the Ford family's control for over 100 years, not every person who has been in charge has been a part of the Ford family. While the Ford family does tend to name some of their sons after the fathers, nowhere are they required to do so. And if you look at how the company was founded, they already disproved what people are trying to put on Waternoose. The naming lineage was not Henry Ford, Sr. > Henry Ford, Jr. > Henry Ford III > Henry Ford IV > Henry Ford V > etc. It was broken when it went from Henry Ford to Edsel Ford.
Any attempt to call Waternoose "Henry J. Waternoose III" is an assumption that families that own a company through several generations are required to have a rigid naming lineage. Further, at the end of the movie, he is credited simply as "Waternoose" and in The Art of Monsters Inc., he is officially listed as "Henry J. Waternoose". —RRabbit42 (leave a message) 06:06, February 16, 2017 (UTC)