From 2006 until 2014, Jack was Vice Chairman of the Supervisory Board of Evides. Prior to that, from 1986 to 2003, Jack worked for PricewaterhouseCoopers NV, where he fulfilled various management functions and was appointed Senior Partner in 1990 and Managing Partner & Territory Leader in 1998, responsible for the Transaction Services practice in the Netherlands. He was employed with the Dutch Ministry of Finance from 1980 to 1986.
Since 2011, Jack is a member of the Supervisory Board and acts as Chairman of the Audit Committee of Corbion NV. In 2018, Jack became a member of the Supervisory Board of Royal Boskalis Westminster NV and in April 2020, he became a member of the Supervisory Board and the Chairman of the Audit Committee of Wolters Kluwer NV. He also serves as a member of the Advisory Council of YGroup Companies since 2018 and became a Non-Executive Board Member of Oranje Fonds in May 2019.
Jack was first appointed to the TomTom Supervisory Board in January 2017. His current term runs until 2021.