diff --git a/ProcessLib/RichardsFlow/RichardsFlowMaterialProperties.h b/ProcessLib/RichardsFlow/RichardsFlowMaterialProperties.h
index 19bdecc51ca7f2e059c3a4048d6847c6d450a9af..4021072673e2c053e34da6915d3caa00b8a061d1 100644
--- a/ProcessLib/RichardsFlow/RichardsFlowMaterialProperties.h
+++ b/ProcessLib/RichardsFlow/RichardsFlowMaterialProperties.h
@@ -42,7 +42,7 @@ namespace RichardsFlow
 * flow.
 */
 
-class RichardsFlowMaterialProperties
+class RichardsFlowMaterialProperties final
 {
 public:
     using ArrayType = MaterialLib::Fluid::FluidProperty::ArrayType;