diff --git a/machofile.py b/machofile.py
index 1d3d28f..0b0726e 100644
--- a/machofile.py
+++ b/machofile.py
@@ -371,6 +371,7 @@ def __init__(self, file_path=None, data=None):
             self.fh.close()
         else:
             self.data = data
+            self.file_path = None
 
         self.f = io.BytesIO(self.data)