On June 16, 1933 Franklin Delano Roosevelt (FDR) got ready to sign the bill that would restrain banks from selling Securities, as well as forcing the banks to choose between commercial and investment banking as a speciality. Stopping them from selling Securities stopped them from investing in the stock market. That day was a big in terms of the economic depression. In stopping the the sales of Securities and establishing the FDIC, it sought out to stop a future depression from banks being financially involved in the stock-market. 

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In the center FDR signs the Banking act of 1933; to the left is senator Carter Glass, to the right Harry B. Seagall.