diff --git a/src/things/abstract/user-groups.ts b/src/things/abstract/user-groups.ts
new file mode 100644
index 00000000..1750cb8c
--- /dev/null
+++ b/src/things/abstract/user-groups.ts
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2021 StApps
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+/**
+ * Types of data consumers
+ */
+export type SCUserGroup =
+  'students'
+  | 'employees'
+  | 'guests';
diff --git a/src/things/message.ts b/src/things/message.ts
index d7ff9113..cf4f6da8 100644
--- a/src/things/message.ts
+++ b/src/things/message.ts
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2019 StApps
+ * Copyright (C) 2019-2021 StApps
  * This program is free software: you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the Free
  * Software Foundation, version 3.
@@ -22,6 +22,7 @@ import {
 } from './abstract/creative-work';
 import {SCThingMeta, SCThingType} from './abstract/thing';
 import {SCThingThatCanBeOfferedTranslatableProperties} from './abstract/thing-that-can-be-offered';
+import {SCUserGroup} from './abstract/user-groups';
 import {SCOrganizationWithoutReferences} from './organization';
 
 /**
@@ -39,7 +40,7 @@ export interface SCMessageWithoutReferences
    *
    * @filterable
    */
-  audiences: SCMessageAudience[];
+  audiences: SCUserGroup[];
 
   /**
    * When the message was created
@@ -90,14 +91,6 @@ export interface SCMessage
   type: SCThingType.Message;
 }
 
-/**
- * Audiences for messages
- */
-export type SCMessageAudience =
-  'students'
-  | 'employees'
-  | 'guests';
-
 /**
  * Translatable properties of a message
  */