Who I Am
I’m a partner at Deloitte Legal and Head of the Greenille Private Client team, which I lead since 2017. As a lawyer I have over 20 years of relevant experience advising entrepreneurs and families on protecting, structuring and growing their businesses and wealth. I am active at our Zaventem office.
What I Do
- Advise families on wealth protection, structuring and risk management
- Design tax-efficient strategies for family businesses and high-net-worth individuals
- Structure private (art) collections, yachts and charitable giving
- Lead the Greenille Private Client team of 30+ lawyers and experts, delivering holistic services across tax, legal, family dynamics and conflict handling
Who I Work With
- High-net-worth individuals and entrepreneurial families
- Family offices in Belgium and internationally
- Deloitte Legal’s multidisciplinary teams and Deloitte’s global network
My Approach
- Combine technical excellence with a pragmatic, solution-oriented mindset
- Align legal and tax structuring with family values and long-term goals
- Focus on sensitive family matters with a human and empathetic approach
Credentials & Leadership
- Head of Deloitte Legal’s Greenille Private Client team since 2017
- Tax & Legal Private Leader for Deloitte Legal Belgium
- Member of STEP Benelux, IFA and BATL and the bar since 2002
Recognition
- Consistently ranked in Chambers High Net Worth annual guide
- Client testimonial: Deloitte Legal is recognised as having “a strong team, whose excellent, in-depth technical knowledge is combined with a very pragmatic and solution-oriented approach. Mathieu Ex is an absolute tier one private wealth adviser. His technical knowledge is impeccable, but it’s his human approach that sets him apart from other advisers.”
- Chambers High Net Worth (Private Wealth Law respondent): “Mathieu is technically brilliant and a very enjoyable person to work with. He has the gift of combining the human side with the technical side.”
Why Deloitte Legal
We bring together Belgium’s largest Private Client team, offering integrated advice that combines tax, legal and family dynamics expertise. Through Deloitte’s global network, we efficiently tackle cross-border challenges and deliver solutions inspired by international best practices.