Portrait of Marc Greisen

Marc Greisen

Principal Development Manager


Marc Greisen is a Principal Development Manager in the New Security Ventures group. He joined Microsoft in 2006. He is currently leading the REST API Fuzz Testing project which incorporates New Security Ventures RESTler project as a primary API fuzzing tool.

Prior to joining Microsoft Research, Marc worked on the Azure guest VM agent, a critical component that runs in every virtual machine in the Azure cloud. Before joining Microsoft, Marc worked for Physio Control a medical device company, working on the first public access defibrillator as an intern. This turned into a number of firsts over the following 15 years, including being a part of the transition to digital recording of data in medical devices and computer systems deployed as medical devices in emergency departments.

Marc also was a principle at a startup that developed a new way of delivering training content to the fire service. Prior to this work, training consisted of watching videos demonstrating situational problems. With the ability to use networked machines, the startup made it possible for training officers to develop, deploy, and interact with fireman while on shift. Allowing for the development of unique scenarios particular to a fire district while making it possible for the training to happen at the fire station instead of requiring firemen to gather at the central administration building.