diff --git a/schema/defs-image.json b/schema/defs-image.json
index ad584dac0..c2623c053 100644
--- a/schema/defs-image.json
+++ b/schema/defs-image.json
@@ -83,14 +83,7 @@
     },
     "annotations": {
       "id": "https://opencontainers.org/schema/image/annotations",
-      "oneOf": [
-        {
-          "$ref": "defs.json#/definitions/mapStringString"
-        },
-        {
-          "type": "null"
-        }
-      ]
+      "$ref": "defs.json#/definitions/mapStringString"
     }
   }
 }