diff --git a/specification/json/sections/cper-arm-processor.json b/specification/json/sections/cper-arm-processor.json
index d4df6dd..bc733c9 100644
--- a/specification/json/sections/cper-arm-processor.json
+++ b/specification/json/sections/cper-arm-processor.json
@@ -106,6 +106,7 @@
                         "additionalProperties": false,
                         "minProperties": 1,
                         "maxProperties": 1,
+                        "required": [],
                         "properties": {
                             "cacheError": {
                                 "type": "object",