diff --git a/lib/reducers/user-reducer.js b/lib/reducers/user-reducer.js
--- a/lib/reducers/user-reducer.js
+++ b/lib/reducers/user-reducer.js
@@ -430,9 +430,13 @@
     if (action.payload.keyserverID !== authoritativeKeyserverID()) {
       return [state, [], []];
     }
-    const newUserInfos = _keyBy(userInfo => userInfo.id)(
+    const keyserverUserInfos = _keyBy(userInfo => userInfo.id)(
       action.payload.userInfos,
     );
+    const newUserInfos = discardKeyserverUsernames(
+      keyserverUserInfos,
+      state.userInfos,
+    );
     const userStoreOps: $ReadOnlyArray<UserStoreOperation> = [
       { type: 'remove_all_users' },
       ...convertUserInfosToReplaceUserOps(newUserInfos),