diff --git a/services/real-time/app/js/AuthorizationManager.js b/services/real-time/app/js/AuthorizationManager.js
index a545594479..0c37ac1423 100644
--- a/services/real-time/app/js/AuthorizationManager.js
+++ b/services/real-time/app/js/AuthorizationManager.js
@@ -1,6 +1,8 @@
 /* eslint-disable
     camelcase,
 */
+const { NotAuthorizedError } = require('./Errors')
+
 let AuthorizationManager
 module.exports = AuthorizationManager = {
   assertClientCanViewProject(client, callback) {
@@ -23,7 +25,7 @@ module.exports = AuthorizationManager = {
     if (allowedLevels.includes(client.ol_context.privilege_level)) {
       callback(null)
     } else {
-      callback(new Error('not authorized'))
+      callback(new NotAuthorizedError())
     }
   },
 
@@ -49,7 +51,7 @@ module.exports = AuthorizationManager = {
     if (client.ol_context[`doc:${doc_id}`] === 'allowed') {
       callback(null)
     } else {
-      callback(new Error('not authorized'))
+      callback(new NotAuthorizedError())
     }
   },
 
diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 7a039c54c1..57190b75e5 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -21,6 +21,12 @@ class MissingSessionError extends OError {
   }
 }
 
+class NotAuthorizedError extends OError {
+  constructor() {
+    super('not authorized')
+  }
+}
+
 class NullBytesInOpError extends OError {
   constructor(jsonChange) {
     super('null bytes found in op', { jsonChange })
@@ -37,6 +43,7 @@ module.exports = {
   CodedError,
   DataTooLargeToParseError,
   MissingSessionError,
+  NotAuthorizedError,
   NullBytesInOpError,
   UpdateTooLargeError
 }