diff --git a/source/RobotAPI/drivers/WeissHapticSensor/WeissHapticSensor.h b/source/RobotAPI/drivers/WeissHapticSensor/WeissHapticSensor.h
index 52d63ca275d6e09bfc42056d23bb0a52ec41ae08..c81fe5df11bf1c144663c13b46b673f7c2182b03 100644
--- a/source/RobotAPI/drivers/WeissHapticSensor/WeissHapticSensor.h
+++ b/source/RobotAPI/drivers/WeissHapticSensor/WeissHapticSensor.h
@@ -7,6 +7,7 @@
 #include "TactileSensor.h"
 #include <RobotAPI/interface/units/HapticUnit.h>
 #include <Core/util/variants/eigen3/Eigen3VariantObjectFactories.h>
+#include <Core/util/variants/eigen3/Eigen3LibRegistry.h>
 #include "TextWriter.h"
 #include <Core/observers/variant/TimestampVariant.h>
 #include <Core/util/variants/eigen3/MatrixVariant.h>
diff --git a/source/RobotAPI/units/HapticObserver.h b/source/RobotAPI/units/HapticObserver.h
index 90edb9b7931d22c858797ad0bc40edb55346d1b6..9b8fa165507e35d268662dfb415f5aa962994de7 100644
--- a/source/RobotAPI/units/HapticObserver.h
+++ b/source/RobotAPI/units/HapticObserver.h
@@ -27,6 +27,7 @@
 #include <RobotAPI/interface/units/HapticUnit.h>
 #include <Core/observers/Observer.h>
 #include <Core/util/variants/eigen3/MatrixVariant.h>
+#include <Core/util/variants/eigen3/Eigen3LibRegistry.h>
 #include <Core/util/variants/eigen3/Eigen3VariantObjectFactories.h>
 #include <Core/core/services/tasks/PeriodicTask.h>