diff --git a/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.cpp b/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.cpp
index 518e48ceb..7920d415d 100644
--- a/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.cpp
+++ b/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.cpp
@@ -574,6 +574,10 @@ namespace Opm {
         return static_cast<size_t>(ecl_grid_get_nactive( c_ptr() ));
     }
 
+    bool EclipseGrid::allActive( ) const {
+        return (getNumActive() == getCartesianSize());
+    }
+
     bool EclipseGrid::cellActive( size_t globalIndex ) const {
         assertGlobalIndex( globalIndex );
         return ecl_grid_cell_active1( c_ptr() , static_cast<int>(globalIndex));
diff --git a/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.hpp b/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.hpp
index 7942aeae2..ccf4f7e0b 100644
--- a/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.hpp
+++ b/opm/parser/eclipse/EclipseState/Grid/EclipseGrid.hpp
@@ -83,6 +83,7 @@ namespace Opm {
         static bool hasCornerPointKeywords(const Deck&);
         static bool hasCartesianKeywords(const Deck&);
         size_t  getNumActive( ) const;
+        bool allActive() const;
 
         size_t activeIndex(size_t i, size_t j, size_t k) const;
         size_t activeIndex(size_t globalIndex) const;