diff --git a/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.cpp b/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.cpp
index 95afd5115c8563d5de220585c003f958b35d6a3c..f4e31dc2700a401330c00cc47ec8a0f76bedc792 100644
--- a/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.cpp
+++ b/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.cpp
@@ -16,7 +16,7 @@ namespace MaterialPropertyLib
 {
 std::unique_ptr<MaterialSpatialDistributionMap>
 createMaterialSpatialDistributionMap(
-    std::map<int, std::unique_ptr<Medium>> const& media,
+    std::map<int, std::shared_ptr<Medium>> const& media,
     MeshLib::Mesh const& mesh)
 {
     auto const material_ids = materialIDs(mesh);
diff --git a/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.h b/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.h
index 8d60b9c5f6db8fd0f3681b41f5401295ee2e38dd..2062e86fe5821a38bf383675313002eb1d2fdaab 100644
--- a/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.h
+++ b/MaterialLib/MPL/CreateMaterialSpatialDistributionMap.h
@@ -26,6 +26,6 @@ class Medium;
 
 std::unique_ptr<MaterialSpatialDistributionMap>
 createMaterialSpatialDistributionMap(
-    std::map<int, std::unique_ptr<Medium>> const& media,
+    std::map<int, std::shared_ptr<Medium>> const& media,
     MeshLib::Mesh const& mesh);
 }  // namespace MaterialPropertyLib
diff --git a/MaterialLib/MPL/MaterialSpatialDistributionMap.h b/MaterialLib/MPL/MaterialSpatialDistributionMap.h
index 06c86509e764abec5daf135f82cf5edf0175898c..f51f94a0d3d4b5d0132b369edfd74f03ac2454f1 100644
--- a/MaterialLib/MPL/MaterialSpatialDistributionMap.h
+++ b/MaterialLib/MPL/MaterialSpatialDistributionMap.h
@@ -29,7 +29,7 @@ class MaterialSpatialDistributionMap
 {
 public:
     MaterialSpatialDistributionMap(
-        std::map<int, std::unique_ptr<Medium>> const& media,
+        std::map<int, std::shared_ptr<Medium>> const& media,
         MeshLib::PropertyVector<int> const* const material_ids)
         : _media(media), _material_ids(material_ids)
     {
@@ -38,7 +38,7 @@ public:
     Medium* getMedium(std::size_t element_id);
 
 private:
-    std::map<int, std::unique_ptr<Medium>> const& _media;
+    std::map<int, std::shared_ptr<Medium>> const& _media;
     MeshLib::PropertyVector<int> const* const _material_ids;
 };
 }  // namespace MaterialPropertyLib