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John Koudounis

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John Koudounis

President and CEO, Calamos Investments
John Koudounis

John Koudounis joined Calamos Investments as Chief Executive Officer in 2016. He became the firm’s first designated CEO hired by Founder John Calamos, Sr., as part of Calamos’ succession plan. A driving force behind improving strategic initiatives, Mr. Koudounis plays a critical role in delivering innovative solutions to business development and expanding product breadth for the firm’s global base of clients. Under his leadership, firm profitability and AUM growth have increased substantially. Mr. Koudounis has over 30 years of financial services experience including executive leadership in the global securities business and a deep background in global capital markets. Most recently, he served as President and CEO of Mizuho Securities USA, one of the world’s largest full-service financial institutions. During his tenure at Mizuho Securities, he built the firm into a full-service investment bank, expanding its debt and equity capital markets teams. Because of his leadership, the firm also grew in profitability, number of clients, and product diversification, allowing Mizuho to be considered globally as a top tier investment bank. Prior to joining Mizuho in 2008, he was Managing Director and Head of Fixed Income for ABN AMRO Americas where he played a critical role in that firm’s successful growth. Mr. Koudounis, often sought after for his thought leadership, serves as a speaker at conferences worldwide and appears frequently on financial news programs including CNN, Fox Business, CNBC, Bloomberg TV, TD Ameritrade Network, Yahoo Finance Live, and others.