diff --git a/etc/default_data.json b/etc/default_data.json
index 403d74a54..4b10d3b4c 100644
--- a/etc/default_data.json
+++ b/etc/default_data.json
@@ -20834,7 +20834,7 @@
             ],
             "user_name": "Mateusz Kowalski",
             "github_id": "mkowalski",
-            "emails": ["mateusz@mkowalski.com"]
+            "emails": ["mateusz@mkowalski.com", "m@kowalski.xyz", "mateusz.kowalski@alumni.cern"]
         },
         {
             "launchpad_id": "maksimov",