diff --git a/lib/types/message-types.js b/lib/types/message-types.js
index d702fc7f7..f3bf3bf72 100644
--- a/lib/types/message-types.js
+++ b/lib/types/message-types.js
@@ -1,518 +1,519 @@
 // @flow
 
 import invariant from 'invariant';
 
 import type { FetchResultInfoInterface } from '../utils/fetch-json';
 import { type ClientDBMediaInfo } from './media-types';
 import type {
   AddMembersMessageData,
   AddMembersMessageInfo,
   RawAddMembersMessageInfo,
 } from './messages/add-members';
 import type {
   ChangeRoleMessageData,
   ChangeRoleMessageInfo,
   RawChangeRoleMessageInfo,
 } from './messages/change-role';
 import type {
   ChangeSettingsMessageData,
   ChangeSettingsMessageInfo,
   RawChangeSettingsMessageInfo,
 } from './messages/change-settings';
 import type {
   CreateEntryMessageData,
   CreateEntryMessageInfo,
   RawCreateEntryMessageInfo,
 } from './messages/create-entry';
 import type {
   CreateSidebarMessageData,
   CreateSidebarMessageInfo,
   RawCreateSidebarMessageInfo,
 } from './messages/create-sidebar';
 import type {
   CreateSubthreadMessageData,
   CreateSubthreadMessageInfo,
   RawCreateSubthreadMessageInfo,
 } from './messages/create-subthread';
 import type {
   CreateThreadMessageData,
   CreateThreadMessageInfo,
   RawCreateThreadMessageInfo,
 } from './messages/create-thread';
 import type {
   DeleteEntryMessageData,
   DeleteEntryMessageInfo,
   RawDeleteEntryMessageInfo,
 } from './messages/delete-entry';
 import type {
   EditEntryMessageData,
   EditEntryMessageInfo,
   RawEditEntryMessageInfo,
 } from './messages/edit-entry';
 import type {
   ImagesMessageData,
   ImagesMessageInfo,
   RawImagesMessageInfo,
 } from './messages/images';
 import type {
   JoinThreadMessageData,
   JoinThreadMessageInfo,
   RawJoinThreadMessageInfo,
 } from './messages/join-thread';
 import type {
   LeaveThreadMessageData,
   LeaveThreadMessageInfo,
   RawLeaveThreadMessageInfo,
 } from './messages/leave-thread';
 import type {
   MediaMessageData,
   MediaMessageInfo,
   RawMediaMessageInfo,
 } from './messages/media';
 import type {
   RawRemoveMembersMessageInfo,
   RemoveMembersMessageData,
   RemoveMembersMessageInfo,
 } from './messages/remove-members';
 import type {
   RawRestoreEntryMessageInfo,
   RestoreEntryMessageData,
   RestoreEntryMessageInfo,
 } from './messages/restore-entry';
 import type {
   RawTextMessageInfo,
   TextMessageData,
   TextMessageInfo,
 } from './messages/text';
 import type {
   RawUnsupportedMessageInfo,
   UnsupportedMessageInfo,
 } from './messages/unsupported';
 import type {
   RawUpdateRelationshipMessageInfo,
   UpdateRelationshipMessageData,
   UpdateRelationshipMessageInfo,
 } from './messages/update-relationship';
 import { type RelativeUserInfo, type UserInfos } from './user-types';
 
 export const messageTypes = Object.freeze({
   TEXT: 0,
   CREATE_THREAD: 1,
   ADD_MEMBERS: 2,
   CREATE_SUB_THREAD: 3,
   CHANGE_SETTINGS: 4,
   REMOVE_MEMBERS: 5,
   CHANGE_ROLE: 6,
   LEAVE_THREAD: 7,
   JOIN_THREAD: 8,
   CREATE_ENTRY: 9,
   EDIT_ENTRY: 10,
   DELETE_ENTRY: 11,
   RESTORE_ENTRY: 12,
   // When the server has a message to deliver that the client can't properly
   // render because the client is too old, the server will send this message
   // type instead. Consequently, there is no MessageData for UNSUPPORTED - just
   // a RawMessageInfo and a MessageInfo. Note that native/persist.js handles
   // converting these MessageInfos when the client is upgraded.
   UNSUPPORTED: 13,
   IMAGES: 14,
   MULTIMEDIA: 15,
   UPDATE_RELATIONSHIP: 16,
   SIDEBAR_SOURCE: 17,
   CREATE_SIDEBAR: 18,
 });
 export type MessageType = $Values<typeof messageTypes>;
 export function assertMessageType(ourMessageType: number): MessageType {
   invariant(
     ourMessageType === 0 ||
       ourMessageType === 1 ||
       ourMessageType === 2 ||
       ourMessageType === 3 ||
       ourMessageType === 4 ||
       ourMessageType === 5 ||
       ourMessageType === 6 ||
       ourMessageType === 7 ||
       ourMessageType === 8 ||
       ourMessageType === 9 ||
       ourMessageType === 10 ||
       ourMessageType === 11 ||
       ourMessageType === 12 ||
       ourMessageType === 13 ||
       ourMessageType === 14 ||
       ourMessageType === 15 ||
       ourMessageType === 16 ||
       ourMessageType === 17 ||
       ourMessageType === 18,
     'number is not MessageType enum',
   );
   return ourMessageType;
 }
 
 const composableMessageTypes = new Set([
   messageTypes.TEXT,
   messageTypes.IMAGES,
   messageTypes.MULTIMEDIA,
 ]);
 export function isComposableMessageType(ourMessageType: MessageType): boolean {
   return composableMessageTypes.has(ourMessageType);
 }
 export function assertComposableMessageType(
   ourMessageType: MessageType,
 ): MessageType {
   invariant(
     isComposableMessageType(ourMessageType),
     'MessageType is not composed',
   );
   return ourMessageType;
 }
 export function assertComposableRawMessage(
   message: RawMessageInfo,
 ): RawComposableMessageInfo {
   invariant(
     message.type === messageTypes.TEXT ||
       message.type === messageTypes.IMAGES ||
       message.type === messageTypes.MULTIMEDIA,
     'Message is not composable',
   );
   return message;
 }
 export function messageDataLocalID(messageData: MessageData): ?string {
   if (
     messageData.type !== messageTypes.TEXT &&
     messageData.type !== messageTypes.IMAGES &&
     messageData.type !== messageTypes.MULTIMEDIA
   ) {
     return null;
   }
   return messageData.localID;
 }
 
 const mediaMessageTypes = new Set([
   messageTypes.IMAGES,
   messageTypes.MULTIMEDIA,
 ]);
 export function isMediaMessageType(ourMessageType: MessageType): boolean {
   return mediaMessageTypes.has(ourMessageType);
 }
 export function assetMediaMessageType(
   ourMessageType: MessageType,
 ): MessageType {
   invariant(isMediaMessageType(ourMessageType), 'MessageType is not media');
   return ourMessageType;
 }
 
 // *MessageData = passed to createMessages function to insert into database
 // Raw*MessageInfo = used by server, and contained in client's local store
 // *MessageInfo = used by client in UI code
 
 export type SidebarSourceMessageData = {
   +type: 17,
   +threadID: string,
   +creatorID: string,
   +time: number,
   +sourceMessage?: RawComposableMessageInfo | RawRobotextMessageInfo,
 };
 export type MessageData =
   | TextMessageData
   | CreateThreadMessageData
   | AddMembersMessageData
   | CreateSubthreadMessageData
   | ChangeSettingsMessageData
   | RemoveMembersMessageData
   | ChangeRoleMessageData
   | LeaveThreadMessageData
   | JoinThreadMessageData
   | CreateEntryMessageData
   | EditEntryMessageData
   | DeleteEntryMessageData
   | RestoreEntryMessageData
   | ImagesMessageData
   | MediaMessageData
   | UpdateRelationshipMessageData
   | SidebarSourceMessageData
   | CreateSidebarMessageData;
 
 export type MultimediaMessageData = ImagesMessageData | MediaMessageData;
 
 export type RawMultimediaMessageInfo =
   | RawImagesMessageInfo
   | RawMediaMessageInfo;
 export type RawComposableMessageInfo =
   | RawTextMessageInfo
   | RawMultimediaMessageInfo;
 
 export type RawRobotextMessageInfo =
   | RawCreateThreadMessageInfo
   | RawAddMembersMessageInfo
   | RawCreateSubthreadMessageInfo
   | RawChangeSettingsMessageInfo
   | RawRemoveMembersMessageInfo
   | RawChangeRoleMessageInfo
   | RawLeaveThreadMessageInfo
   | RawJoinThreadMessageInfo
   | RawCreateEntryMessageInfo
   | RawEditEntryMessageInfo
   | RawDeleteEntryMessageInfo
   | RawRestoreEntryMessageInfo
   | RawUpdateRelationshipMessageInfo
   | RawCreateSidebarMessageInfo
   | RawUnsupportedMessageInfo;
 export type RawSidebarSourceMessageInfo = {
   ...SidebarSourceMessageData,
   id: string,
 };
 export type RawMessageInfo =
   | RawComposableMessageInfo
   | RawRobotextMessageInfo
   | RawSidebarSourceMessageInfo;
 
 export type LocallyComposedMessageInfo =
   | ({
       ...RawImagesMessageInfo,
       +localID: string,
     } & RawImagesMessageInfo)
   | ({
       ...RawMediaMessageInfo,
       +localID: string,
     } & RawMediaMessageInfo)
   | ({
       ...RawTextMessageInfo,
       +localID: string,
     } & RawTextMessageInfo);
 
 export type MultimediaMessageInfo = ImagesMessageInfo | MediaMessageInfo;
 export type ComposableMessageInfo = TextMessageInfo | MultimediaMessageInfo;
 
 export type RobotextMessageInfo =
   | CreateThreadMessageInfo
   | AddMembersMessageInfo
   | CreateSubthreadMessageInfo
   | ChangeSettingsMessageInfo
   | RemoveMembersMessageInfo
   | ChangeRoleMessageInfo
   | LeaveThreadMessageInfo
   | JoinThreadMessageInfo
   | CreateEntryMessageInfo
   | EditEntryMessageInfo
   | DeleteEntryMessageInfo
   | RestoreEntryMessageInfo
   | UnsupportedMessageInfo
   | UpdateRelationshipMessageInfo
   | CreateSidebarMessageInfo;
 export type PreviewableMessageInfo =
   | RobotextMessageInfo
   | MultimediaMessageInfo;
 export type SidebarSourceMessageInfo = {
   +type: 17,
   +id: string,
   +threadID: string,
   +creator: RelativeUserInfo,
   +time: number,
   +sourceMessage: ComposableMessageInfo | RobotextMessageInfo,
 };
 
 export type MessageInfo =
   | ComposableMessageInfo
   | RobotextMessageInfo
   | SidebarSourceMessageInfo;
 
 export type ThreadMessageInfo = {
   messageIDs: string[],
   startReached: boolean,
   lastNavigatedTo: number, // millisecond timestamp
   lastPruned: number, // millisecond timestamp
 };
 
 // Tracks client-local information about a message that hasn't been assigned an
 // ID by the server yet. As soon as the client gets an ack from the server for
 // this message, it will clear the LocalMessageInfo.
 export type LocalMessageInfo = {
   +sendFailed?: boolean,
 };
 
 export type MessageStore = {
   +messages: { +[id: string]: RawMessageInfo },
   +threads: { +[threadID: string]: ThreadMessageInfo },
   +local: { +[id: string]: LocalMessageInfo },
   +currentAsOf: number,
 };
 
 export type RemoveMessageOperation = {
   +type: 'remove',
   +payload: { +ids: $ReadOnlyArray<string> },
 };
 
 export type RemoveMessagesForThreadsOperation = {
   +type: 'remove_messages_for_threads',
   +payload: { +threadIDs: $ReadOnlyArray<string> },
 };
 
 export type ReplaceMessageOperation = {
   +type: 'replace',
   +payload: { +id: string, +messageInfo: RawMessageInfo },
 };
 
 export type RekeyMessageOperation = {
   +type: 'rekey',
   +payload: { +from: string, +to: string },
 };
 
 export type RemoveAllMessagesOperation = {
   +type: 'remove_all',
 };
 
 export type ClientDBMessageInfo = {
   +id: string,
   +local_id: ?string,
   +thread: string,
   +user: string,
   +type: string,
   +future_type: ?string,
   +content: ?string,
   +time: string,
   +media_infos: ?$ReadOnlyArray<ClientDBMediaInfo>,
 };
 
 export type ClientDBReplaceMessageOperation = {
   +type: 'replace',
   +payload: ClientDBMessageInfo,
 };
 
 export type MessageStoreOperation =
   | RemoveMessageOperation
   | ReplaceMessageOperation
   | RekeyMessageOperation
   | RemoveMessagesForThreadsOperation
   | RemoveAllMessagesOperation;
 
 export type ClientDBMessageStoreOperation =
   | RemoveMessageOperation
   | ClientDBReplaceMessageOperation
   | RekeyMessageOperation
   | RemoveMessagesForThreadsOperation
   | RemoveAllMessagesOperation;
 
 export const messageTruncationStatus = Object.freeze({
   // EXHAUSTIVE means we've reached the start of the thread. Either the result
   // set includes the very first message for that thread, or there is nothing
   // behind the cursor you queried for. Given that the client only ever issues
   // ranged queries whose range, when unioned with what is in state, represent
   // the set of all messages for a given thread, we can guarantee that getting
   // EXHAUSTIVE means the start has been reached.
   EXHAUSTIVE: 'exhaustive',
   // TRUNCATED is rare, and means that the server can't guarantee that the
   // result set for a given thread is contiguous with what the client has in its
   // state. If the client can't verify the contiguousness itself, it needs to
   // replace its Redux store's contents with what it is in this payload.
   //  1) getMessageInfosSince: Result set for thread is equal to max, and the
   //     truncation status isn't EXHAUSTIVE (ie. doesn't include the very first
   //     message).
   //  2) getMessageInfos: MessageSelectionCriteria does not specify cursors, the
   //     result set for thread is equal to max, and the truncation status isn't
   //     EXHAUSTIVE. If cursors are specified, we never return truncated, since
   //     the cursor given us guarantees the contiguousness of the result set.
   // Note that in the reducer, we can guarantee contiguousness if there is any
   // intersection between messageIDs in the result set and the set currently in
   // the Redux store.
   TRUNCATED: 'truncated',
   // UNCHANGED means the result set is guaranteed to be contiguous with what the
   // client has in its state, but is not EXHAUSTIVE. Basically, it's anything
   // that isn't either EXHAUSTIVE or TRUNCATED.
   UNCHANGED: 'unchanged',
 });
 export type MessageTruncationStatus = $Values<typeof messageTruncationStatus>;
 export function assertMessageTruncationStatus(
   ourMessageTruncationStatus: string,
 ): MessageTruncationStatus {
   invariant(
     ourMessageTruncationStatus === 'truncated' ||
       ourMessageTruncationStatus === 'unchanged' ||
       ourMessageTruncationStatus === 'exhaustive',
     'string is not ourMessageTruncationStatus enum',
   );
   return ourMessageTruncationStatus;
 }
 export type MessageTruncationStatuses = {
   [threadID: string]: MessageTruncationStatus,
 };
 
 export type ThreadCursors = { +[threadID: string]: ?string };
 
 export type MessageSelectionCriteria = {
   +threadCursors?: ?ThreadCursors,
   +joinedThreads?: ?boolean,
   +newerThan?: ?number,
 };
 
 export type FetchMessageInfosRequest = {
   +cursors: ThreadCursors,
   +numberPerThread?: ?number,
 };
 export type FetchMessageInfosResponse = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatuses: MessageTruncationStatuses,
   +userInfos: UserInfos,
 };
 export type FetchMessageInfosResult = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatuses: MessageTruncationStatuses,
 };
 export type FetchMessageInfosPayload = {
   +threadID: string,
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatus: MessageTruncationStatus,
 };
 export type MessagesResponse = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +truncationStatuses: MessageTruncationStatuses,
   +currentAsOf: number,
 };
 export const defaultNumberPerThread = 20;
+export const defaultMaxMessageAge = 14 * 24 * 60 * 60 * 1000; // 2 weeks
 
 export type SendMessageResponse = {
   +newMessageInfo: RawMessageInfo,
 };
 export type SendMessageResult = {
   +id: string,
   +time: number,
   +interface: FetchResultInfoInterface,
 };
 export type SendMessagePayload = {
   +localID: string,
   +serverID: string,
   +threadID: string,
   +time: number,
   +interface: FetchResultInfoInterface,
 };
 
 export type SendTextMessageRequest = {
   +threadID: string,
   +localID?: string,
   +text: string,
 };
 export type SendMultimediaMessageRequest = {
   +threadID: string,
   +localID: string,
   +mediaIDs: $ReadOnlyArray<string>,
 };
 
 // Used for the message info included in log-in type actions
 export type GenericMessagesResult = {
   +messageInfos: RawMessageInfo[],
   +truncationStatus: MessageTruncationStatuses,
   +watchedIDsAtRequestTime: $ReadOnlyArray<string>,
   +currentAsOf: number,
 };
 
 export type SaveMessagesPayload = {
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   +updatesCurrentAsOf: number,
 };
 
 export type NewMessagesPayload = {
   +messagesResult: MessagesResponse,
 };
 
 export type MessageStorePrunePayload = {
   +threadIDs: $ReadOnlyArray<string>,
 };
diff --git a/server/src/fetchers/message-fetchers.js b/server/src/fetchers/message-fetchers.js
index 9b6763208..845b34ab0 100644
--- a/server/src/fetchers/message-fetchers.js
+++ b/server/src/fetchers/message-fetchers.js
@@ -1,624 +1,633 @@
 // @flow
 
 import invariant from 'invariant';
 
 import {
   sortMessageInfoList,
   shimUnsupportedRawMessageInfos,
 } from 'lib/shared/message-utils';
 import { messageSpecs } from 'lib/shared/messages/message-specs';
 import { notifCollapseKeyForRawMessageInfo } from 'lib/shared/notif-utils';
 import {
   type RawMessageInfo,
   type RawComposableMessageInfo,
   type RawRobotextMessageInfo,
   messageTypes,
   type MessageType,
   assertMessageType,
   type MessageSelectionCriteria,
   type MessageTruncationStatus,
   messageTruncationStatus,
   type FetchMessageInfosResult,
+  defaultMaxMessageAge,
 } from 'lib/types/message-types';
 import { threadPermissions } from 'lib/types/thread-types';
 import { ServerError } from 'lib/utils/errors';
 
 import {
   dbQuery,
   SQL,
   mergeOrConditions,
   mergeAndConditions,
 } from '../database/database';
 import type { PushInfo } from '../push/send';
 import type { Viewer } from '../session/viewer';
 import { creationString, localIDFromCreationString } from '../utils/idempotent';
 import { mediaFromRow } from './upload-fetchers';
 
 export type CollapsableNotifInfo = {
   collapseKey: ?string,
   existingMessageInfos: RawMessageInfo[],
   newMessageInfos: RawMessageInfo[],
 };
 export type FetchCollapsableNotifsResult = {
   [userID: string]: CollapsableNotifInfo[],
 };
 
 const visibleExtractString = `$.${threadPermissions.VISIBLE}.value`;
 
 // This function doesn't filter RawMessageInfos based on what messageTypes the
 // client supports, since each user can have multiple clients. The caller must
 // handle this filtering.
 async function fetchCollapsableNotifs(
   pushInfo: PushInfo,
 ): Promise<FetchCollapsableNotifsResult> {
   // First, we need to fetch any notifications that should be collapsed
   const usersToCollapseKeysToInfo = {};
   const usersToCollapsableNotifInfo = {};
   for (const userID in pushInfo) {
     usersToCollapseKeysToInfo[userID] = {};
     usersToCollapsableNotifInfo[userID] = [];
     for (const rawMessageInfo of pushInfo[userID].messageInfos) {
       const collapseKey = notifCollapseKeyForRawMessageInfo(rawMessageInfo);
       if (!collapseKey) {
         const collapsableNotifInfo = {
           collapseKey,
           existingMessageInfos: [],
           newMessageInfos: [rawMessageInfo],
         };
         usersToCollapsableNotifInfo[userID].push(collapsableNotifInfo);
         continue;
       }
       if (!usersToCollapseKeysToInfo[userID][collapseKey]) {
         usersToCollapseKeysToInfo[userID][collapseKey] = {
           collapseKey,
           existingMessageInfos: [],
           newMessageInfos: [],
         };
       }
       usersToCollapseKeysToInfo[userID][collapseKey].newMessageInfos.push(
         rawMessageInfo,
       );
     }
   }
 
   const sqlTuples = [];
   for (const userID in usersToCollapseKeysToInfo) {
     const collapseKeysToInfo = usersToCollapseKeysToInfo[userID];
     for (const collapseKey in collapseKeysToInfo) {
       sqlTuples.push(
         SQL`(n.user = ${userID} AND n.collapse_key = ${collapseKey})`,
       );
     }
   }
 
   if (sqlTuples.length === 0) {
     return usersToCollapsableNotifInfo;
   }
 
   const collapseQuery = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type,
       m.user AS creatorID, stm.permissions AS subthread_permissions, n.user,
       n.collapse_key, up.id AS uploadID, up.type AS uploadType,
       up.secret AS uploadSecret, up.extra AS uploadExtra
     FROM notifications n
     LEFT JOIN messages m ON m.id = n.message
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = n.user
     LEFT JOIN memberships stm
       ON m.type = ${messageTypes.CREATE_SUB_THREAD}
         AND stm.thread = m.content AND stm.user = n.user
     WHERE n.rescinded = 0 AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE AND
   `;
   collapseQuery.append(mergeOrConditions(sqlTuples));
   collapseQuery.append(SQL`ORDER BY m.time DESC`);
   const [collapseResult] = await dbQuery(collapseQuery);
 
   const rowsByUser = new Map();
   for (const row of collapseResult) {
     const user = row.user.toString();
     const currentRowsForUser = rowsByUser.get(user);
     if (currentRowsForUser) {
       currentRowsForUser.push(row);
     } else {
       rowsByUser.set(user, [row]);
     }
   }
 
   const derivedMessages = await fetchDerivedMessages(collapseResult);
   for (const userRows of rowsByUser.values()) {
     const messages = parseMessageSQLResult(userRows, derivedMessages);
     for (const message of messages) {
       const { rawMessageInfo, rows } = message;
       const [row] = rows;
       const info = usersToCollapseKeysToInfo[row.user][row.collapse_key];
       info.existingMessageInfos.push(rawMessageInfo);
     }
   }
 
   for (const userID in usersToCollapseKeysToInfo) {
     const collapseKeysToInfo = usersToCollapseKeysToInfo[userID];
     for (const collapseKey in collapseKeysToInfo) {
       const info = collapseKeysToInfo[collapseKey];
       usersToCollapsableNotifInfo[userID].push({
         collapseKey: info.collapseKey,
         existingMessageInfos: sortMessageInfoList(info.existingMessageInfos),
         newMessageInfos: sortMessageInfoList(info.newMessageInfos),
       });
     }
   }
 
   return usersToCollapsableNotifInfo;
 }
 
 type MessageSQLResult = $ReadOnlyArray<{
   rawMessageInfo: RawMessageInfo,
   rows: $ReadOnlyArray<Object>,
 }>;
 function parseMessageSQLResult(
   rows: $ReadOnlyArray<Object>,
   derivedMessages: $ReadOnlyMap<
     string,
     RawComposableMessageInfo | RawRobotextMessageInfo,
   >,
   viewer?: Viewer,
 ): MessageSQLResult {
   const rowsByID = new Map();
   for (const row of rows) {
     const id = row.id.toString();
     const currentRowsForID = rowsByID.get(id);
     if (currentRowsForID) {
       currentRowsForID.push(row);
     } else {
       rowsByID.set(id, [row]);
     }
   }
 
   const messages = [];
   for (const messageRows of rowsByID.values()) {
     const rawMessageInfo = rawMessageInfoFromRows(
       messageRows,
       viewer,
       derivedMessages,
     );
     if (rawMessageInfo) {
       messages.push({ rawMessageInfo, rows: messageRows });
     }
   }
 
   return messages;
 }
 
 function assertSingleRow(rows: $ReadOnlyArray<Object>): Object {
   if (rows.length === 0) {
     throw new Error('expected single row, but none present!');
   } else if (rows.length !== 1) {
     const messageIDs = rows.map(row => row.id.toString());
     console.warn(
       `expected single row, but there are multiple! ${messageIDs.join(', ')}`,
     );
   }
   return rows[0];
 }
 
 function mostRecentRowType(rows: $ReadOnlyArray<Object>): MessageType {
   if (rows.length === 0) {
     throw new Error('expected row, but none present!');
   }
   return assertMessageType(rows[0].type);
 }
 
 function rawMessageInfoFromRows(
   rows: $ReadOnlyArray<Object>,
   viewer?: Viewer,
   derivedMessages: $ReadOnlyMap<
     string,
     RawComposableMessageInfo | RawRobotextMessageInfo,
   >,
 ): ?RawMessageInfo {
   const type = mostRecentRowType(rows);
   const messageSpec = messageSpecs[type];
 
   if (type === messageTypes.IMAGES || type === messageTypes.MULTIMEDIA) {
     const media = rows.filter(row => row.uploadID).map(mediaFromRow);
     const [row] = rows;
     const localID = localIDFromCreationString(viewer, row.creation);
     invariant(
       messageSpec.rawMessageInfoFromServerDBRow,
       `multimedia message spec should have rawMessageInfoFromServerDBRow`,
     );
     return messageSpec.rawMessageInfoFromServerDBRow(row, {
       media,
       derivedMessages,
       localID,
     });
   }
 
   const row = assertSingleRow(rows);
   const localID = localIDFromCreationString(viewer, row.creation);
   invariant(
     messageSpec.rawMessageInfoFromServerDBRow,
     `message spec ${type} should have rawMessageInfoFromServerDBRow`,
   );
   return messageSpec.rawMessageInfoFromServerDBRow(row, {
     derivedMessages,
     localID,
   });
 }
 
 async function fetchMessageInfos(
   viewer: Viewer,
   criteria: MessageSelectionCriteria,
   numberPerThread: number,
 ): Promise<FetchMessageInfosResult> {
   const selectionClause = messageSelectionCriteriaToSQLClause(criteria);
   const truncationStatuses = {};
 
   const viewerID = viewer.id;
   const query = SQL`
     SELECT * FROM (
       SELECT x.id, x.content, x.time, x.type, x.user AS creatorID,
         x.creation, x.subthread_permissions, x.uploadID, x.uploadType,
         x.uploadSecret, x.uploadExtra,
         @num := if(
           @thread = x.thread,
           if(@message = x.id, @num, @num + 1),
           1
         ) AS number,
         @message := x.id AS messageID,
         @thread := x.thread AS threadID
       FROM (SELECT @num := 0, @thread := '', @message := '') init
       JOIN (
         SELECT m.id, m.thread, m.user, m.content, m.time, m.type,
           m.creation, stm.permissions AS subthread_permissions,
           up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret,
           up.extra AS uploadExtra
         FROM messages m
         LEFT JOIN uploads up
           ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
             AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
         LEFT JOIN memberships mm
           ON mm.thread = m.thread AND mm.user = ${viewerID}
         LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
           AND stm.thread = m.content AND stm.user = ${viewerID}
         WHERE JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE AND
   `;
   query.append(selectionClause);
   query.append(SQL`
         ORDER BY m.thread, m.time DESC
       ) x
     ) y
     WHERE y.number <= ${numberPerThread}
   `);
   const [result] = await dbQuery(query);
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   const messages = parseMessageSQLResult(result, derivedMessages, viewer);
 
   const rawMessageInfos = [];
   const threadToMessageCount = new Map();
   for (const message of messages) {
     const { rawMessageInfo } = message;
     rawMessageInfos.push(rawMessageInfo);
     const { threadID } = rawMessageInfo;
     const currentCountValue = threadToMessageCount.get(threadID);
     const currentCount = currentCountValue ? currentCountValue : 0;
     threadToMessageCount.set(threadID, currentCount + 1);
   }
 
   for (const [threadID, messageCount] of threadToMessageCount) {
     // If there are fewer messages returned than the max for a given thread,
     // then our result set includes all messages in the query range for that
     // thread
     truncationStatuses[threadID] =
       messageCount < numberPerThread
         ? messageTruncationStatus.EXHAUSTIVE
         : messageTruncationStatus.TRUNCATED;
   }
 
   for (const rawMessageInfo of rawMessageInfos) {
     if (messageSpecs[rawMessageInfo.type].startsThread) {
       truncationStatuses[rawMessageInfo.threadID] =
         messageTruncationStatus.EXHAUSTIVE;
     }
   }
 
   for (const threadID in criteria.threadCursors) {
     const truncationStatus = truncationStatuses[threadID];
     if (truncationStatus === null || truncationStatus === undefined) {
       // If nothing was returned for a thread that was explicitly queried for,
       // then our result set includes all messages in the query range for that
       // thread
       truncationStatuses[threadID] = messageTruncationStatus.EXHAUSTIVE;
     } else if (truncationStatus === messageTruncationStatus.TRUNCATED) {
       // If a cursor was specified for a given thread, then the result is
       // guaranteed to be contiguous with what the client has, and as such the
       // result should never be TRUNCATED
       truncationStatuses[threadID] = messageTruncationStatus.UNCHANGED;
     }
   }
 
   const shimmedRawMessageInfos = shimUnsupportedRawMessageInfos(
     rawMessageInfos,
     viewer.platformDetails,
   );
 
   return {
     rawMessageInfos: shimmedRawMessageInfos,
     truncationStatuses,
   };
 }
 
 function messageSelectionCriteriaToSQLClause(
   criteria: MessageSelectionCriteria,
 ) {
+  const minMessageTime = Date.now() - defaultMaxMessageAge;
+
+  let globalTimeFilter;
+  if (criteria.newerThan) {
+    globalTimeFilter = SQL`m.time > ${criteria.newerThan}`;
+  } else if (!criteria.threadCursors) {
+    globalTimeFilter = SQL`m.time > ${minMessageTime}`;
+  }
+
   const threadConditions = [];
-  if (criteria.joinedThreads === true) {
+  if (criteria.joinedThreads === true && !globalTimeFilter) {
+    threadConditions.push(SQL`(mm.role > 0 AND m.time > ${minMessageTime})`);
+  } else if (criteria.joinedThreads === true) {
     threadConditions.push(SQL`mm.role > 0`);
   }
   if (criteria.threadCursors) {
     for (const threadID in criteria.threadCursors) {
       const cursor = criteria.threadCursors[threadID];
       if (cursor) {
         threadConditions.push(
           SQL`(m.thread = ${threadID} AND m.id < ${cursor})`,
         );
       } else {
         threadConditions.push(SQL`m.thread = ${threadID}`);
       }
     }
   }
   if (threadConditions.length === 0) {
     throw new ServerError('internal_error');
   }
   const threadClause = mergeOrConditions(threadConditions);
 
-  const conditions = [threadClause];
-  if (criteria.newerThan) {
-    conditions.push(SQL`m.time > ${criteria.newerThan}`);
-  }
+  const conditions = [globalTimeFilter, threadClause].filter(Boolean);
   return mergeAndConditions(conditions);
 }
 
 function messageSelectionCriteriaToInitialTruncationStatuses(
   criteria: MessageSelectionCriteria,
   defaultTruncationStatus: MessageTruncationStatus,
 ) {
   const truncationStatuses = {};
   if (criteria.threadCursors) {
     for (const threadID in criteria.threadCursors) {
       truncationStatuses[threadID] = defaultTruncationStatus;
     }
   }
   return truncationStatuses;
 }
 
 async function fetchMessageInfosSince(
   viewer: Viewer,
   criteria: MessageSelectionCriteria,
   maxNumberPerThread: number,
 ): Promise<FetchMessageInfosResult> {
   const selectionClause = messageSelectionCriteriaToSQLClause(criteria);
   const truncationStatuses = messageSelectionCriteriaToInitialTruncationStatuses(
     criteria,
     messageTruncationStatus.UNCHANGED,
   );
 
   const viewerID = viewer.id;
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type,
       m.creation, m.user AS creatorID, stm.permissions AS subthread_permissions,
       up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret,
       up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewerID}
     LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
       AND stm.thread = m.content AND stm.user = ${viewerID}
     WHERE JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE AND
   `;
   query.append(selectionClause);
   query.append(SQL`
     ORDER BY m.thread, m.time DESC
   `);
   const [result] = await dbQuery(query);
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   const messages = parseMessageSQLResult(result, derivedMessages, viewer);
 
   const rawMessageInfos = [];
   let currentThreadID = null;
   let numMessagesForCurrentThreadID = 0;
   for (const message of messages) {
     const { rawMessageInfo } = message;
     const { threadID } = rawMessageInfo;
     if (threadID !== currentThreadID) {
       currentThreadID = threadID;
       numMessagesForCurrentThreadID = 1;
       truncationStatuses[threadID] = messageTruncationStatus.UNCHANGED;
     } else {
       numMessagesForCurrentThreadID++;
     }
     if (numMessagesForCurrentThreadID <= maxNumberPerThread) {
       if (messageSpecs[rawMessageInfo.type].startsThread) {
         truncationStatuses[threadID] = messageTruncationStatus.EXHAUSTIVE;
       }
       rawMessageInfos.push(rawMessageInfo);
     } else if (numMessagesForCurrentThreadID === maxNumberPerThread + 1) {
       truncationStatuses[threadID] = messageTruncationStatus.TRUNCATED;
     }
   }
 
   const shimmedRawMessageInfos = shimUnsupportedRawMessageInfos(
     rawMessageInfos,
     viewer.platformDetails,
   );
 
   return {
     rawMessageInfos: shimmedRawMessageInfos,
     truncationStatuses,
   };
 }
 
 function getMessageFetchResultFromRedisMessages(
   viewer: Viewer,
   rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
 ): FetchMessageInfosResult {
   const truncationStatuses = {};
   for (const rawMessageInfo of rawMessageInfos) {
     truncationStatuses[rawMessageInfo.threadID] =
       messageTruncationStatus.UNCHANGED;
   }
   const shimmedRawMessageInfos = shimUnsupportedRawMessageInfos(
     rawMessageInfos,
     viewer.platformDetails,
   );
   return {
     rawMessageInfos: shimmedRawMessageInfos,
     truncationStatuses,
   };
 }
 
 async function fetchMessageInfoForLocalID(
   viewer: Viewer,
   localID: ?string,
 ): Promise<?RawMessageInfo> {
   if (!localID || !viewer.hasSessionInfo) {
     return null;
   }
   const creation = creationString(viewer, localID);
   const viewerID = viewer.id;
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation,
       m.user AS creatorID, stm.permissions AS subthread_permissions,
       up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret,
       up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewerID}
     LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
       AND stm.thread = m.content AND stm.user = ${viewerID}
     WHERE m.user = ${viewerID} AND m.creation = ${creation} AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE
   `;
 
   const [result] = await dbQuery(query);
   if (result.length === 0) {
     return null;
   }
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   return rawMessageInfoFromRows(result, viewer, derivedMessages);
 }
 
 const entryIDExtractString = '$.entryID';
 async function fetchMessageInfoForEntryAction(
   viewer: Viewer,
   messageType: MessageType,
   entryID: string,
   threadID: string,
 ): Promise<?RawMessageInfo> {
   const viewerID = viewer.id;
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation,
       m.user AS creatorID, up.id AS uploadID, up.type AS uploadType,
       up.secret AS uploadSecret, up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewerID}
     WHERE m.user = ${viewerID} AND m.thread = ${threadID} AND
       m.type = ${messageType} AND
       JSON_EXTRACT(m.content, ${entryIDExtractString}) = ${entryID} AND
       JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE
   `;
 
   const [result] = await dbQuery(query);
   if (result.length === 0) {
     return null;
   }
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   return rawMessageInfoFromRows(result, viewer, derivedMessages);
 }
 
 async function fetchMessageRowsByIDs(messageIDs: $ReadOnlyArray<string>) {
   const query = SQL`
     SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation, 
       m.user AS creatorID, stm.permissions AS subthread_permissions,
       up.id AS uploadID, up.type AS uploadType, up.secret AS uploadSecret, 
       up.extra AS uploadExtra
     FROM messages m
     LEFT JOIN uploads up
       ON m.type IN (${[messageTypes.IMAGES, messageTypes.MULTIMEDIA]})
         AND JSON_CONTAINS(m.content, CAST(up.id as JSON), '$')
     LEFT JOIN memberships stm ON m.type = ${messageTypes.CREATE_SUB_THREAD}
       AND stm.thread = m.content AND stm.user = m.user
     WHERE m.id IN (${messageIDs})
   `;
   const [result] = await dbQuery(query);
   return result;
 }
 
 async function fetchDerivedMessages(
   rows: $ReadOnlyArray<Object>,
   viewer?: Viewer,
 ): Promise<
   $ReadOnlyMap<string, RawComposableMessageInfo | RawRobotextMessageInfo>,
 > {
   const requiredIDs = new Set<string>();
   for (const row of rows) {
     if (row.type === messageTypes.SIDEBAR_SOURCE) {
       const content = JSON.parse(row.content);
       requiredIDs.add(content.sourceMessageID);
     }
   }
 
   const messagesByID = new Map<
     string,
     RawComposableMessageInfo | RawRobotextMessageInfo,
   >();
   if (requiredIDs.size === 0) {
     return messagesByID;
   }
 
   const result = await fetchMessageRowsByIDs([...requiredIDs]);
   const messages = parseMessageSQLResult(result, new Map(), viewer);
 
   for (const message of messages) {
     const { rawMessageInfo } = message;
     if (rawMessageInfo.id) {
       invariant(
         rawMessageInfo.type !== messageTypes.SIDEBAR_SOURCE,
         'SIDEBAR_SOURCE should not point to a SIDEBAR_SOURCE',
       );
       messagesByID.set(rawMessageInfo.id, rawMessageInfo);
     }
   }
   return messagesByID;
 }
 
 async function fetchMessageInfoByID(
   viewer?: Viewer,
   messageID: string,
 ): Promise<?RawMessageInfo> {
   const result = await fetchMessageRowsByIDs([messageID]);
   if (result.length === 0) {
     return null;
   }
   const derivedMessages = await fetchDerivedMessages(result, viewer);
   return rawMessageInfoFromRows(result, viewer, derivedMessages);
 }
 
 export {
   fetchCollapsableNotifs,
   fetchMessageInfos,
   fetchMessageInfosSince,
   getMessageFetchResultFromRedisMessages,
   fetchMessageInfoForLocalID,
   fetchMessageInfoForEntryAction,
   fetchMessageInfoByID,
 };