diff --git a/src/server/api/endpoints/users/groups/joined.ts b/src/server/api/endpoints/users/groups/joined.ts
index 853a2510d..97d168e52 100644
--- a/src/server/api/endpoints/users/groups/joined.ts
+++ b/src/server/api/endpoints/users/groups/joined.ts
@@ -32,7 +32,9 @@ export default define(meta, async (ps, me) => {
 
 	const joinings = await UserGroupJoinings.find({
 		userId: me.id,
-		userGroupId: Not(In(ownedGroups.map(x => x.id)))
+		...(ownedGroups.length > 0 ? {
+			userGroupId: Not(In(ownedGroups.map(x => x.id)))
+		} : {})
 	});
 
 	return await Promise.all(joinings.map(x => UserGroups.pack(x.userGroupId)));