Michael Spencer began his career in 1976, as an investment analyst at Simon and Coates. In 1980, he joined Drexel Burnham Lambert where he spent three years broking futures.
Between 1983 and 1986, Spencer was a director at money broker Charles Fulton, until his involvement in the new interest rate swaps market led him to set up Intercapital in 1986. Intercapital grew over 10 years from four original staffers to over 300 employees with offices in London, New York and Sydney.
In October 1998, Intercapital merged with EXCO, a listed money broker. The following year it merged again with Garban to form ICAP and named Spencer as its chief executive. In 2016, ICAP sold its global hybrid voice broking business to Tullett Prebon and the remaining ICAP businesses formed a new company called NEX Group where Spencer remained as chief executive.
In 2018, NEX reached an agreement to be acquired by CME Group. After completion of the transaction, Spencer joined the CME Board in addition to working as a special adviser focused on integrating the business and evolving its client offerings.
Spencer was named the Ernst & Young World Entrepreneur of the Year 2010.