Siebert was born to a Jewish family in Cleveland, Ohio. Siebert began her career working at various brokerages. In 1967, she founded her own eponymous firm, Muriel Siebert & Co., Inc., beginning by doing research for institutions, and buying and selling financial analyses. That same year, she applied for a seat on the New York Stock Exchange. Of the first ten investors she asked to sponsor her application, nine denied her.

The NYSE itself insisted on a new condition before considering Siebert’s application. It insisted that Siebert obtain a letter from a bank offering loans of $300,000 at the near-record $445,000 seat price. But banks would not commit to lending her the money until the NYSE agreed to admit her. Siebert finally was elected to membership on December 28, 1967. In 1975, when the Securities and Exchange Commission first permitted broker commissions to be negotiable, she criticized the discount brokers vehemently; she ran numerous ads calling the discounters and the rates “low ball”.

In 1977, she was named Superintendent of Banks for the State of New York, with oversight of all of the banks in the state, regulating about $500 billion. Not one bank failed during her tenure, despite failures nationwide. When she learned Hugh Carey, New York Governor at the time, had appointed her to the position, Siebert recalled thinking, “Mickie, you know you’re a college dropout. You’ve done pretty well as a college dropout!”

Shortly after returning to her firm, she ran in the Republican primary for the Senate seat of Daniel Patrick Moynihan. She finished second behind State Assemblywoman Florence Sullivan, who went on to lose to Moynihan in November 1982. 

In the mid-1990s, Siebert & Co. reverse merged with a furniture holding company, J. Michael & Sons, that was liquidating, thereby, becoming a publicly-traded company. Siebert remained President of her eponymous firm and continued to be a sought-after commentator on phenomena in financial markets.

According to en.wikipedia.org. Source of photos: internet