Marc Tarpenning is an American entrepreneur and business executive. He is best known for co-founding Tesla Motors with Elon Musk and Martin Eberhard in 2003. Tarpenning served as the Chief Financial Officer and Treasurer of Tesla until 2007, and he played a key role in the development and launch of the Tesla Roadster, the company's first electric sports car. After leaving Tesla, Tarpenning co-founded the energy storage company Aquion Energy, where he served as Chief Executive Officer until 2016. He has also served as a mentor to other entrepreneurs and startups through various programs and initiatives. It is likely that he continues to mentor and advise entrepreneurs and businesses in the tech and energy sectors.