diff --git a/opm/autodiff/BlackoilWellModel_impl.hpp b/opm/autodiff/BlackoilWellModel_impl.hpp
index c13370a1d..6c74685ff 100644
--- a/opm/autodiff/BlackoilWellModel_impl.hpp
+++ b/opm/autodiff/BlackoilWellModel_impl.hpp
@@ -1737,7 +1737,7 @@ namespace Opm {
                 const auto& segments = well.segments;
 
                 // \Note: eventually we need to hanlde the situations that some segments are shut
-                assert( 1u + segment_set.size() == segments.size());
+                assert(0u + segment_set.size() == segments.size());
 
                 for (const auto& segment : segments) {
                     const int segment_index = segment_set.segmentNumberToIndex(segment.first);