diff --git a/OpenRA.Mods.Common/Scripting/Properties/ConditionProperties.cs b/OpenRA.Mods.Common/Scripting/Properties/ConditionProperties.cs
index 71d7b22894..a55a5efa55 100644
--- a/OpenRA.Mods.Common/Scripting/Properties/ConditionProperties.cs
+++ b/OpenRA.Mods.Common/Scripting/Properties/ConditionProperties.cs
@@ -50,7 +50,8 @@ namespace OpenRA.Mods.Common.Scripting
 		public void RevokeCondition(int token)
 		{
 			foreach (var external in externalConditions)
-				external.TryRevokeCondition(Self, this, token);
+				if (external.TryRevokeCondition(Self, this, token))
+					break;
 		}
 
 		[Desc("Check whether this actor accepts a specific external condition.")]
diff --git a/OpenRA.Mods.Common/Traits/Conditions/ExternalCondition.cs b/OpenRA.Mods.Common/Traits/Conditions/ExternalCondition.cs
index 8e9c0ab91d..4a16e56a61 100644
--- a/OpenRA.Mods.Common/Traits/Conditions/ExternalCondition.cs
+++ b/OpenRA.Mods.Common/Traits/Conditions/ExternalCondition.cs
@@ -130,10 +130,20 @@ namespace OpenRA.Mods.Common.Traits
 			if (conditionManager == null || source == null)
 				return false;
 
-			var removed = permanentTokens.GetOrAdd(source).Remove(token) ||
-				timedTokens.GetOrAdd(source).RemoveWhere(t => t.Token == token) > 0;
+			HashSet<int> permanentTokensForSource;
+			if (permanentTokens.TryGetValue(source, out permanentTokensForSource))
+			{
+				if (!permanentTokensForSource.Remove(token))
+					return false;
+			}
+			else
+			{
+				HashSet<TimedToken> timedTokensForSource = null;
+				if (timedTokens.TryGetValue(source, out timedTokensForSource) && timedTokensForSource.RemoveWhere(t => t.Token == token) == 0)
+					return false;
+			}
 
-			if (removed && conditionManager.TokenValid(self, token))
+			if (conditionManager.TokenValid(self, token))
 				conditionManager.RevokeCondition(self, token);
 
 			return true;
diff --git a/OpenRA.Mods.Common/Traits/Conditions/LineBuildSegmentExternalCondition.cs b/OpenRA.Mods.Common/Traits/Conditions/LineBuildSegmentExternalCondition.cs
index c78414ef0d..ddd1d368b2 100644
--- a/OpenRA.Mods.Common/Traits/Conditions/LineBuildSegmentExternalCondition.cs
+++ b/OpenRA.Mods.Common/Traits/Conditions/LineBuildSegmentExternalCondition.cs
@@ -56,7 +56,8 @@ namespace OpenRA.Mods.Common.Traits
 				return;
 
 			foreach (var external in segment.TraitsImplementing<ExternalCondition>())
-				external.TryRevokeCondition(segment, self, token);
+				if (external.TryRevokeCondition(segment, self, token))
+					break;
 		}
 
 		void INotifyLineBuildSegmentsChanged.SegmentAdded(Actor self, Actor segment)
diff --git a/OpenRA.Mods.Common/Traits/Conditions/ProximityExternalCondition.cs b/OpenRA.Mods.Common/Traits/Conditions/ProximityExternalCondition.cs
index f38322ca78..d6057fbd9d 100644
--- a/OpenRA.Mods.Common/Traits/Conditions/ProximityExternalCondition.cs
+++ b/OpenRA.Mods.Common/Traits/Conditions/ProximityExternalCondition.cs
@@ -156,7 +156,8 @@ namespace OpenRA.Mods.Common.Traits
 
 			tokens.Remove(a);
 			foreach (var external in a.TraitsImplementing<ExternalCondition>())
-				external.TryRevokeCondition(a, self, token);
+				if (external.TryRevokeCondition(a, self, token))
+					break;
 		}
 	}
 }