diff --git a/mortgageAPI.yaml b/mortgageAPI.yaml
index 94540c0..94e89a0 100644
--- a/mortgageAPI.yaml
+++ b/mortgageAPI.yaml
@@ -1,6 +1,6 @@
 openapi: 3.0.0
 info:
-  version: 3.6.0
+  version: 4.0.0
   title: Common Mortgage API (Public)
   description: >
     This specification defines a common mortgage API for mortgages as used in Switzerland.