diff --git a/lib/icinga/checkable-comment.cpp b/lib/icinga/checkable-comment.cpp
index 29fc65563..71cfac619 100644
--- a/lib/icinga/checkable-comment.cpp
+++ b/lib/icinga/checkable-comment.cpp
@@ -19,7 +19,7 @@ void Checkable::RemoveAllComments()
 	}
 }
 
-void Checkable::RemoveAckComments(const String& removedBy)
+void Checkable::RemoveAckComments(const String& removedBy, double createdBefore)
 {
 	for (const Comment::Ptr& comment : GetComments()) {
 		if (comment->GetEntryType() == CommentAcknowledgement) {
@@ -28,6 +28,10 @@ void Checkable::RemoveAckComments(const String& removedBy)
 				continue;
 			}
 
+			if (comment->GetEntryTime() > createdBefore) {
+				continue;
+			}
+
 			{
 				ObjectLock oLock (comment);
 				comment->SetRemovedBy(removedBy);
diff --git a/lib/icinga/checkable.hpp b/lib/icinga/checkable.hpp
index 96df5bd47..3d48b1445 100644
--- a/lib/icinga/checkable.hpp
+++ b/lib/icinga/checkable.hpp
@@ -17,6 +17,7 @@
 #include <condition_variable>
 #include <cstdint>
 #include <functional>
+#include <limits>
 
 namespace icinga
 {
@@ -156,7 +157,7 @@ public:
 
 	/* Comments */
 	void RemoveAllComments();
-	void RemoveAckComments(const String& removedBy = String());
+	void RemoveAckComments(const String& removedBy = String(), double createdBefore = std::numeric_limits<double>::max());
 
 	std::set<Comment::Ptr> GetComments() const;
 	Comment::Ptr GetLastComment() const;