diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/TaskComponent.java b/ganttzk/src/main/java/org/zkoss/ganttz/TaskComponent.java
index 326751d62..1cdbdc555 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/TaskComponent.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/TaskComponent.java
@@ -320,7 +320,7 @@ public class TaskComponent extends Div implements AfterCompose {
 
     public boolean isMovingTasksEnabled() {
         return disabilityConfiguration.isMovingTasksEnabled()
-                && !task.isSubcontracted();
+                && task.canBeExplicitlyMoved();
     }
 
     void doUpdatePosition(String leftX, String topY) {
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/data/Milestone.java b/ganttzk/src/main/java/org/zkoss/ganttz/data/Milestone.java
index 35e71f44c..da1a24646 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/Milestone.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/Milestone.java
@@ -71,4 +71,9 @@ public class Milestone extends Task {
         return false;
     }
 
+    @Override
+    public boolean canBeExplicitlyMoved() {
+        return true;
+    }
+
 }
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java b/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java
index fc85a3214..b09460b93 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java
@@ -314,4 +314,5 @@ public abstract class Task implements ITaskFundamentalProperties {
         return fundamentalProperties.canBeExplicitlyResized();
     }
 
+    public abstract boolean canBeExplicitlyMoved();
 }
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskContainer.java b/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskContainer.java
index 08e0c863e..2aaf9c9ba 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskContainer.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskContainer.java
@@ -208,4 +208,9 @@ public class TaskContainer extends Task {
         return true;
     }
 
+    @Override
+    public boolean canBeExplicitlyMoved() {
+        return false;
+    }
+
 }
\ No newline at end of file
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskLeaf.java b/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskLeaf.java
index 1f3ce5a79..a6f0a805b 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskLeaf.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/TaskLeaf.java
@@ -52,4 +52,9 @@ public class TaskLeaf extends Task {
         return false;
     }
 
+    @Override
+    public boolean canBeExplicitlyMoved() {
+        return !isSubcontracted();
+    }
+
 }