Mark Heising founded Medley Partners, a private market investment firm, in 2004. Previously he was the Founder of VLSI Cores, which designed and licensed cryptographic integrated circuits. He holds six U.S. Patents in cryptography, compression and data communications. Mark is Chair of the Environmental Defense Fund. He is a Trustee for the Institute for Advanced Study and a Board member for the Heising-Simons Foundation and the Heising-Simons Action Fund. Mark and his wife, Liz Simons, took the Giving Pledge in 2016, publicly committing the majority of their wealth to philanthropic causes. Mark earned a BS in Physics and a MS in Electrical Engineering and Computer Sciences from the University of California at Berkeley.

Mark Heising and Liz Simons founded the Foundation in 2007 . You can read the letter they wrote about why they joined the Giving Pledge here.