diff --git a/keyserver/src/creators/role-creator.js b/keyserver/src/creators/role-creator.js
--- a/keyserver/src/creators/role-creator.js
+++ b/keyserver/src/creators/role-creator.js
@@ -95,6 +95,7 @@
   const openTopLevelDescendantJoinThread =
     OPEN_TOP_LEVEL_DESCENDANT + threadPermissions.JOIN_THREAD;
   const openChildJoinThread = OPEN_CHILD + threadPermissions.JOIN_THREAD;
+  const openChildAddMembers = OPEN_CHILD + threadPermissions.ADD_MEMBERS;
 
   const genesisMemberPermissions = {
     [threadPermissions.KNOW_OF]: true,
@@ -107,7 +108,9 @@
     ...genesisMemberPermissions,
     [threadPermissions.LEAVE_THREAD]: true,
     [threadPermissions.CREATE_SIDEBARS]: true,
+    [threadPermissions.ADD_MEMBERS]: true,
     [openChildJoinThread]: true,
+    [openChildAddMembers]: true,
   };
 
   let memberPermissions;
diff --git a/keyserver/src/database/migration-config.js b/keyserver/src/database/migration-config.js
--- a/keyserver/src/database/migration-config.js
+++ b/keyserver/src/database/migration-config.js
@@ -203,6 +203,7 @@
       );
     },
   ],
+  [18, updateRolesAndPermissionsForAllThreads],
 ]);
 const newDatabaseVersion: number = Math.max(...migrations.keys());