A Paris administrative court of appeal ordered LVMH CEO Bernard Arnault and his wife to pay nearly €22.5 million in additional taxes.
The total assessment equals approximately $25.7 million.
The ruling covers unpaid taxes and social contributions from 2010.
It also includes wealth solidarity taxes assessed for the period between 2012 and 2015.
The dispute stems from the complex shareholding structure of LVMH Moët Hennessy Louis Vuitton.
A spokesperson confirmed Arnault will appeal the decision to the Council of State, France's highest administrative court.
Arnault remains Europe's wealthiest person with an estimated net worth of $165 billion.