diff --git a/definitions/3.0.0/messageObject.json b/definitions/3.0.0/messageObject.json
index f8cd37bb..1903dc7b 100644
--- a/definitions/3.0.0/messageObject.json
+++ b/definitions/3.0.0/messageObject.json
@@ -46,6 +46,10 @@
       "type": "string",
       "description": "A brief summary of the message."
     },
+    "version": {
+      "type": "string",
+      "description": "A version for the message."
+    },
     "name": {
       "type": "string",
       "description": "Name of the message."
diff --git a/test/definitions/3.0.0/models/channel/message.test.mjs b/test/definitions/3.0.0/models/channel/message.test.mjs
index 99426546..b92e4639 100644
--- a/test/definitions/3.0.0/models/channel/message.test.mjs
+++ b/test/definitions/3.0.0/models/channel/message.test.mjs
@@ -20,6 +20,7 @@ const data = new JsonSchemaTestSuiteData(
     {
       "name": "UserSignup",
       "title": "User signup",
+      "version": "1.0.0",
       "summary": "Action to sign a user up.",
       "description": "A longer description",
       "contentType": "application/json",