diff --git a/specification/json/sections/cper-ia32x64-processor.json b/specification/json/sections/cper-ia32x64-processor.json
index fd9a13e..371e19f 100644
--- a/specification/json/sections/cper-ia32x64-processor.json
+++ b/specification/json/sections/cper-ia32x64-processor.json
@@ -46,6 +46,7 @@
                 "properties": {
                     "type": {
                         "type": "object",
+                        "additionalProperties": false,
                         "required": ["guid", "name"],
                         "properties": {
                             "guid": {