Who is Anton Birnbaum from Black Friday and what is their importance?

Birnbaum is a member of the NY Stock Exchange steering committee and Caitlin's mentor. It's Anton who tells Caitlin of the existence of the Committee of Twelve and their role in various activities. Anton is elderly and an accepted financial genius of the day. It's Anton who outlines the fact that the Committee of Twelve began their plans in response to a plot hatched by Monserrat to gain control of the Western stock market. Anton meets with Caitlin and Carroll to discuss ways to put an end to Green Band and is killed on his way home.