diff --git a/langgraph/graph/graph.py b/langgraph/graph/graph.py
index af9b7bc6c..7c91901c4 100644
--- a/langgraph/graph/graph.py
+++ b/langgraph/graph/graph.py
@@ -207,7 +207,7 @@ class Graph:
             )
         # coerce path_map to a dictionary
         if isinstance(path_map, dict):
-            pass
+            path_map = path_map.copy()
         elif isinstance(path_map, list):
             path_map = {name: name for name in path_map}
         elif rtn_type := get_type_hints(path).get("return"):