diff --git a/keyserver/src/creators/invite-link-creator.js b/keyserver/src/creators/invite-link-creator.js
--- a/keyserver/src/creators/invite-link-creator.js
+++ b/keyserver/src/creators/invite-link-creator.js
@@ -8,6 +8,7 @@
 } from 'lib/types/link-types.js';
 import { threadPermissions } from 'lib/types/thread-permission-types.js';
 import { ServerError } from 'lib/utils/errors.js';
+import { reservedUsernamesSet } from 'lib/utils/reserved-users.js';
 
 import createIDs from './id-creator.js';
 import {
@@ -33,6 +34,9 @@
   if (badWordsFilter.isProfane(request.name)) {
     throw new ServerError('offensive_words');
   }
+  if (reservedUsernamesSet.has(request.name)) {
+    throw new ServerError('link_reserved');
+  }
 
   const permissionPromise = checkThreadPermission(
     viewer,
diff --git a/lib/shared/invite-links.js b/lib/shared/invite-links.js
--- a/lib/shared/invite-links.js
+++ b/lib/shared/invite-links.js
@@ -1,9 +1,12 @@
 // @flow
 
-const inviteLinkErrorMessages = {
+const inviteLinkErrorMessages: { +[string]: string } = {
   invalid_characters: 'Link cannot contain any spaces or special characters',
   offensive_words: 'No offensive or abusive words allowed',
   already_in_use: 'Public link URL already in use',
+  link_reserved:
+    'This public link is currently reserved. Please contact support@' +
+    'comm.app if you would like to claim this link.',
 };
 
 const defaultErrorMessage = 'unknown error';