diff --git a/script/static-checks/check-copyright.py b/script/static-checks/check-copyright.py
index 39863c7..d99aa5d 100755
--- a/script/static-checks/check-copyright.py
+++ b/script/static-checks/check-copyright.py
@@ -180,7 +180,7 @@
 only files that are modified by the latest patch(es).""",
                         action="store_true")
 
-    (rc, stdout, stderr) = utils.shell_command(['git', 'merge-base', 'HEAD', 'master'])
+    (rc, stdout, stderr) = utils.shell_command(['git', 'merge-base', 'HEAD', 'origin/master'])
     if rc:
         print("Git merge-base command failed. Cannot determine base commit.")
         sys.exit(rc)