diff --git a/keyserver/src/fetchers/message-fetchers.js b/keyserver/src/fetchers/message-fetchers.js
--- a/keyserver/src/fetchers/message-fetchers.js
+++ b/keyserver/src/fetchers/message-fetchers.js
@@ -21,6 +21,8 @@
   messageTruncationStatus,
   type FetchMessageInfosResult,
   defaultMaxMessageAge,
+  type FetchPinnedMessagesRequest,
+  type FetchPinnedMessagesResult,
 } from 'lib/types/message-types.js';
 import { threadPermissions } from 'lib/types/thread-types.js';
 import { ServerError } from 'lib/utils/errors.js';
@@ -659,6 +661,50 @@
   return result;
 }
 
+async function fetchPinnedMessageInfos(
+  viewer: Viewer,
+  request: FetchPinnedMessagesRequest,
+): Promise<?FetchPinnedMessagesResult> {
+  const messageRowsQuery = SQL`
+    SELECT m.id, m.thread AS threadID, m.content, m.time, m.type, m.creation,
+      m.user AS creatorID, m.target_message as targetMessageID,
+      NULL AS subthread_permissions, u.id AS uploadID,
+      u.type AS uploadType, u.secret AS uploadSecret, u.extra AS uploadExtra
+    FROM messages m
+    LEFT JOIN uploads u ON u.container = m.id
+    LEFT JOIN memberships mm ON mm.thread = m.thread AND mm.user = ${viewer.id}
+    WHERE m.thread = ${request.threadID} 
+      AND m.pinned = 1
+      AND JSON_EXTRACT(mm.permissions, ${visibleExtractString}) IS TRUE
+  `;
+  const [messageRows] = await dbQuery(messageRowsQuery);
+  if (messageRows.length === 0) {
+    return null;
+  }
+  const derivedMessages = await fetchDerivedMessages(messageRows, viewer);
+
+  const pinnedRawMessageInfos = [];
+  for (const messageRow of messageRows) {
+    const rawMessageInfo = rawMessageInfoFromRows(
+      [messageRow],
+      viewer,
+      derivedMessages,
+    );
+    if (rawMessageInfo) {
+      pinnedRawMessageInfos.push(rawMessageInfo);
+    }
+  }
+
+  const shimmedPinnedRawMessageInfos = shimUnsupportedRawMessageInfos(
+    pinnedRawMessageInfos,
+    viewer.platformDetails,
+  );
+
+  return {
+    pinnedMessages: shimmedPinnedRawMessageInfos,
+  };
+}
+
 async function fetchDerivedMessages(
   rows: $ReadOnlyArray<Object>,
   viewer?: Viewer,
@@ -729,4 +775,5 @@
   fetchMessageInfoForEntryAction,
   fetchMessageInfoByID,
   fetchThreadMessagesCount,
+  fetchPinnedMessageInfos,
 };
diff --git a/lib/types/message-types.js b/lib/types/message-types.js
--- a/lib/types/message-types.js
+++ b/lib/types/message-types.js
@@ -573,3 +573,11 @@
 export type MessageStorePrunePayload = {
   +threadIDs: $ReadOnlyArray<string>,
 };
+
+export type FetchPinnedMessagesRequest = {
+  +threadID: string,
+};
+
+export type FetchPinnedMessagesResult = {
+  +pinnedMessages: $ReadOnlyArray<RawMessageInfo>,
+};