Jonathan Kellner photo

Jonathan Kellner


Members Exchange


Jonathan Kellner is the CEO of Members Exchange (MEMX), a recently launched venture that intends to be an independent U.S. securities exchange. The venture is backed by a diverse group of market participants, including some of the industry’s largest broker-dealers, banks, and market makers. Mr. Kellner is responsible for MEMX’s strategic vision, with an initial focus on assembling the staff, establishing and maintaining a positive workplace culture, and guiding the company through the build-out of its technology platform and the exchange approval process with the SEC.


Prior to accepting the role as MEMX CEO, Mr. Kellner was the CEO of Instinet Incorporated, an institutional agency-only broker and independent equity trading arm of its parent company, Nomura Holdings, Inc. In this role, he led a global organization of 800 team members, including registered broker-dealers in six separate regulatory jurisdictions. During his tenure, Instinet strengthened its leadership position as a global agency broker through the delivery of market-leading execution technology and customer-centric trading innovations. He also led the company through its successful acquisition of BlockCross ATS from State Street, and through periods of significant regulatory change, including Dodd-Frank and MiFID II.


Mr. Kellner spent 11 years at Instinet, serving in a number of different leadership capacities. He began his career in the financial services industry working in a variety of technology and equity trading roles at global financial services firms, including Charles Schwab and Morgan Stanley. He holds a Bachelor of Science degree in mechanical engineering from the University of Michigan.