diff --git a/quads.py b/quads.py
index 74bec9a..1c173ba 100644
--- a/quads.py
+++ b/quads.py
@@ -799,7 +799,8 @@ def insert(self, point, data=None):
             bool: `True` if insertion succeeded, otherwise `False`.
         """
         pnt = self.convert_to_point(point)
-        pnt.data = data
+        if pnt.data is None or data is not None: 
+            pnt.data = data
         return self._root.insert(pnt)
 
     def find(self, point):