David Oliver Sacks (born May 25, 1972) is an entrepreneur and investor in internet technology firms. He is general partner of Craft Ventures, a venture capital fund he co-founded in late 2017. Previously as an entrepreneur, Sacks was the founding COO and product leader of PayPal (acquired by eBay in 2002 for $1.5 billion) and Founder/CEO of Yammer (acquired by Microsoft in 2012 for $1.2 billion). In 2016, he led the turnaround of Zenefits as interim CEO. In 2017, Sacks co-founded blockchain startup Harbor as an incubation of Craft Ventures. His angel investments include Facebook, Uber, SpaceX, Palantir Technologies, Airbnb and Houzz.