Marnix became Chief Legal Officer of Royal Philips and a member of the Executive Committee in 2014. In 2017, he was appointed a member of Philips’ Board of Management. Since 2021, he has been Co-Chair of Philips’ ESG Committee, with responsibility for driving Environmental, Social and Governance efforts across the company, including sustainability. Marnix is responsible for Legal, Intellectual Property & Standards, as well as Government & Public Affairs. In 2011, he was appointed Professor of International Corporate Governance at the Erasmus School of Law in Rotterdam.