diff --git a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableBeginDragTrigger.cs b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableBeginDragTrigger.cs
index fefc213b..1523556e 100644
--- a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableBeginDragTrigger.cs
+++ b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableBeginDragTrigger.cs
@@ -8,6 +8,7 @@
 namespace UniRx.Triggers
 {
     [DisallowMultipleComponent]
+    [RequireComponent(typeof(ObservableDragTrigger))]
     public class ObservableBeginDragTrigger : ObservableTriggerBase, IEventSystemHandler, IBeginDragHandler
     {
         Subject<PointerEventData> onBeginDrag;
diff --git a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableEndDragTrigger.cs b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableEndDragTrigger.cs
index 8d68135f..7fbbb852 100644
--- a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableEndDragTrigger.cs
+++ b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservableEndDragTrigger.cs
@@ -8,6 +8,7 @@
 namespace UniRx.Triggers
 {
     [DisallowMultipleComponent]
+    [RequireComponent(typeof(ObservableDragTrigger))]
     public class ObservableEndDragTrigger : ObservableTriggerBase, IEventSystemHandler, IEndDragHandler
     {
         Subject<PointerEventData> onEndDrag;
diff --git a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservablePointerUpTrigger.cs b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservablePointerUpTrigger.cs
index 877e63aa..b6cff4ba 100644
--- a/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservablePointerUpTrigger.cs
+++ b/Assets/Plugins/UniRx/Scripts/UnityEngineBridge/Triggers/ObservablePointerUpTrigger.cs
@@ -8,6 +8,7 @@
 namespace UniRx.Triggers
 {
     [DisallowMultipleComponent]
+    [RequireComponent(typeof(ObservablePointerDownTrigger))]
     public class ObservablePointerUpTrigger : ObservableTriggerBase, IEventSystemHandler, IPointerUpHandler
     {
         Subject<PointerEventData> onPointerUp;