After December 10, 1930, no person shall at any time carry on the business of a commission merchant, dealer, or broker without a license valid and effective at such time. Any person who violates any provision of this subsection shall be liable to a penalty of not more than $1,000 for each such offense and not more than $250 for each day it continues, which shall accrue to the United States and may be recovered in a civil suit brought by the United States.

Any person violating this provision may, upon a showing satisfactory to the Secretary of Agriculture, or his authorized representative, that such violation was not willful but was due to inadvertence, be permitted by the Secretary, or such representative, to settle his liability in the matter by the payment of the fees due for the period covered by such violation and an additional sum, not in excess of $250, to be fixed by the Secretary of Agriculture or his authorized representative. Such payment shall be deposited in the Treasury of the United States in the same manner as regular license fees.