Mercury Securities LLC, a brokerage firm located in San Rafael, California, was censured and fined $5,000.00 by Financial Industry Regulatory Authority (FINRA) based upon consenting to findings that the firm failed to supervise registered representatives’ private securities transactions. Letter of Acceptance, Waiver and Consent, No. 2015043459301 (July 12, 2017). According to the AWC, three of…