diff --git a/maven/src/org/netbeans/modules/maven/NbMavenProjectImpl.java b/maven/src/org/netbeans/modules/maven/NbMavenProjectImpl.java
--- a/maven/src/org/netbeans/modules/maven/NbMavenProjectImpl.java
+++ b/maven/src/org/netbeans/modules/maven/NbMavenProjectImpl.java
@@ -329,6 +329,7 @@
         if (project == null) {
             project = loadOriginalMavenProject(true);
         }
+        assert project.getProjectBuildingRequest() == null;
         return project;
     }
 
@@ -434,6 +435,11 @@
             }
         }
         assert newproject != null;
+        { // #192155 - release some memory
+            newproject.getParent();
+            newproject.getDistributionManagementArtifactRepository();
+            newproject.setProjectBuildingRequest(null);
+        } // XXX apply to other places where a MavenProject might be created, e.g. reload online
         return newproject;
     }