Nathan typically uses this alias when he needs to be clearly a dirty business man. He will usually attach himself to "The Mark" as either "The Inside Man" or "The Outside Man". He often talks in a modified southern throaty drawl. In both mentions, Bob Gibson is not an expert of the particular industry surrounding the con, but rather an outside investor looking to make money, usually from the Mark.
- "The Underground Job" - Bob Gibson appears, first as "The Outside Man", and when the plan changes, he shifts to "The Inside Man", in The Skagway Shuffle.
Bob Gibson is a former major league baseball pitcher who played for the St. Louis Cardinals.