diff --git a/lib/shacl/algebra/node_shape.rb b/lib/shacl/algebra/node_shape.rb
index a144993..89c5d5f 100644
--- a/lib/shacl/algebra/node_shape.rb
+++ b/lib/shacl/algebra/node_shape.rb
@@ -44,7 +44,7 @@ def conforms(node, depth: 0, **options)
             resultSeverity: options[:severity],
             component: RDF::Vocab::SHACL.ClosedConstraintComponent,
             **options)
-        end.compact
+        end.flatten.compact
       elsif @options[:ignoredProperties]
         raise SHACL::Error, "shape has ignoredProperties without being closed"
       end