This industry comprises establishments primarily engaged in acting as principals (except investment bankers, securities dealers, and commodity contracts dealers) in buying or selling of financial contracts generally on a spread basis. Principals are investors that buy or sell for their own account. Establishments primarily engaged in investment banking, securities dealing, securities brokering, commodity contracts dealing, or commodity contracts brokering are classified in Industry Group 5231, Securities and Commodity Contracts Intermediation and Brokerage.