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Cynthia Julien Warner

Cynthia (CJ) Warner is the president and CEO of Renewable Energy Group Inc., a leading provider of cleaner, lower carbon intensity products and services. Operating internationally, REG is North America’s largest producer of advanced biofuels, utilizing an integrated procurement, distribution and logistics network to convert natural fats, oils, greases and sugars into lower carbon intensity products. She joined the company in 2019, bringing nearly 40 years of experience in energy, oil refining and marketing, renewable fuels commercialization and related technology development.

Prior to REG, CJ served as executive vice president, operations for Andeavor (formerly Tesoro) where she oversaw Andeavor’s 10-refinery, 1.2 million barrels/day production system; extensive logistics system; and environment, health, safety and security groups. During her four-year tenure at Andeavor, the company grew from a market capitalization of less than $10 billion to over $23 billion.

Prior to Andeavor, CJ held executive leadership roles at several global energy companies including Sapphire Energy, British Petroleum, UOP and Amoco. She is a featured leader in the 2008 book Becoming a Resonant Leader: Develop Your Emotional Intelligence (Harvard Business Press) and was named one of Fast Company’s 100 most creative people in business in 2010.

In addition to REG, CJ serves as a member of the Board of Directors for IDEX Corporation. She is a member of the National Petroleum Council and the Board of Visitors of the Vanderbilt University School of Engineering. CJ is also a noteworthy philanthropic supporter of Vanderbilt.

CJ earned a bachelor’s degree in chemical engineering from Vanderbilt University and an MBA from Illinois Institute of Technology.