David Marcus is an American entrepreneur. He is the co-creator of Diem, a cryptocurrency project initiated by Facebook. He is the former president of PayPal and Vice President of Messaging Products at Facebook where he ran the Facebook Messenger unit from 2014 until 2018. In December 2017, Marcus was appointed to the Coinbase Board of Directors, from which he stepped down in 2018. In 2021, he stepped down from Facebook.