diff --git a/keyserver/src/responders/thread-responders.js b/keyserver/src/responders/thread-responders.js
--- a/keyserver/src/responders/thread-responders.js
+++ b/keyserver/src/responders/thread-responders.js
@@ -25,7 +25,6 @@
   type ThreadFetchMediaRequest,
   type ToggleMessagePinRequest,
   type ToggleMessagePinResult,
-  rawThreadInfoValidator,
 } from 'lib/types/thread-types.js';
 import { serverUpdateInfoValidator } from 'lib/types/update-types.js';
 import { userInfosValidator } from 'lib/types/user-types.js';
@@ -102,8 +101,6 @@
 export const changeThreadSettingsResultValidator: TInterface<ChangeThreadSettingsResult> =
   tShape<ChangeThreadSettingsResult>({
     newMessageInfos: t.list(rawMessageInfoValidator),
-    threadInfo: t.maybe(rawThreadInfoValidator),
-    threadInfos: t.maybe(t.dict(tID, rawThreadInfoValidator)),
     updatesResult: tShape({
       newUpdates: t.list(serverUpdateInfoValidator),
     }),
diff --git a/keyserver/src/updaters/thread-permission-updaters.js b/keyserver/src/updaters/thread-permission-updaters.js
--- a/keyserver/src/updaters/thread-permission-updaters.js
+++ b/keyserver/src/updaters/thread-permission-updaters.js
@@ -36,7 +36,6 @@
 import {
   fetchServerThreadInfos,
   rawThreadInfosFromServerThreadInfos,
-  type FetchThreadInfosResult,
 } from '../fetchers/thread-fetchers.js';
 import { rescindPushNotifs } from '../push/rescind.js';
 import { createScriptViewer } from '../session/scripts.js';
@@ -975,7 +974,6 @@
 // only needs to be specified if a JOIN_THREAD update will be generated for the
 // viewer, in which case it's necessary for knowing the set of entries to fetch.
 type ChangesetCommitResult = {
-  ...FetchThreadInfosResult,
   ...CreateUpdatesResult,
 };
 async function commitMembershipChangeset(
@@ -1054,10 +1052,9 @@
     rescindPushNotifsForMemberDeletion(toRescindPushNotifs),
   ]);
 
-  // We fetch all threads here because old clients still expect the full list of
-  // threads on most thread operations. Once verifyClientSupported gates on
-  // codeVersion 62, we can add a WHERE clause on changedThreadIDs here
-  const serverThreadInfoFetchResult = await fetchServerThreadInfos();
+  const serverThreadInfoFetchResult = await fetchServerThreadInfos(
+    SQL`t.id IN (${[...changedThreadIDs]})`,
+  );
   const { threadInfos: serverThreadInfos } = serverThreadInfoFetchResult;
 
   const time = Date.now();
@@ -1117,7 +1114,6 @@
   });
 
   return {
-    ...threadInfoFetchResult,
     userInfos,
     viewerUpdates,
   };
diff --git a/keyserver/src/updaters/thread-updaters.js b/keyserver/src/updaters/thread-updaters.js
--- a/keyserver/src/updaters/thread-updaters.js
+++ b/keyserver/src/updaters/thread-updaters.js
@@ -10,7 +10,6 @@
   getThreadTypeParentRequirement,
   validChatNameRegex,
 } from 'lib/shared/thread-utils.js';
-import { hasMinCodeVersion } from 'lib/shared/version-utils.js';
 import type { Shape } from 'lib/types/core.js';
 import { messageTypes } from 'lib/types/message-types-enum.js';
 import { threadPermissions } from 'lib/types/thread-permission-types.js';
@@ -138,10 +137,7 @@
   }
 
   const changeset = await changeRole(request.threadID, memberIDs, request.role);
-  const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
-    viewer,
-    changeset,
-  );
+  const { viewerUpdates } = await commitMembershipChangeset(viewer, changeset);
 
   const messageData = {
     type: messageTypes.CHANGE_ROLE,
@@ -153,18 +149,7 @@
   };
   const newMessageInfos = await createMessages(viewer, [messageData]);
 
-  if (hasMinCodeVersion(viewer.platformDetails, { native: 62 })) {
-    return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
-  }
-
-  return {
-    threadInfo: threadInfos[request.threadID],
-    threadInfos,
-    updatesResult: {
-      newUpdates: viewerUpdates,
-    },
-    newMessageInfos,
-  };
+  return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
 }
 
 async function removeMembers(
@@ -224,10 +209,7 @@
   }
 
   const changeset = await changeRole(request.threadID, actualMemberIDs, 0);
-  const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
-    viewer,
-    changeset,
-  );
+  const { viewerUpdates } = await commitMembershipChangeset(viewer, changeset);
 
   const newMessageInfos = await (async () => {
     if (actualMemberIDs.length === 0) {
@@ -243,18 +225,7 @@
     return await createMessages(viewer, [messageData]);
   })();
 
-  if (hasMinCodeVersion(viewer.platformDetails, { native: 62 })) {
-    return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
-  }
-
-  return {
-    threadInfo: threadInfos[request.threadID],
-    threadInfos,
-    updatesResult: {
-      newUpdates: viewerUpdates,
-    },
-    newMessageInfos,
-  };
+  return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
 }
 
 async function leaveThread(
@@ -752,18 +723,14 @@
   }
 
   const changeset = { membershipRows, relationshipChangeset };
-  const { threadInfos, viewerUpdates } = await commitMembershipChangeset(
-    viewer,
-    changeset,
-    {
-      // This forces an update for this thread,
-      // regardless of whether any membership rows are changed
-      changedThreadIDs:
-        Object.keys(sqlUpdate).length > 0
-          ? new Set([request.threadID])
-          : new Set(),
-    },
-  );
+  const { viewerUpdates } = await commitMembershipChangeset(viewer, changeset, {
+    // This forces an update for this thread,
+    // regardless of whether any membership rows are changed
+    changedThreadIDs:
+      Object.keys(sqlUpdate).length > 0
+        ? new Set([request.threadID])
+        : new Set(),
+  });
 
   let newMessageInfos = [];
   if (!silenceMessages) {
@@ -792,18 +759,7 @@
     newMessageInfos = await createMessages(viewer, messageDatas);
   }
 
-  if (hasMinCodeVersion(viewer.platformDetails, { native: 62 })) {
-    return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
-  }
-
-  return {
-    threadInfo: threadInfos[request.threadID],
-    threadInfos,
-    updatesResult: {
-      newUpdates: viewerUpdates,
-    },
-    newMessageInfos,
-  };
+  return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
 }
 
 async function joinThread(
diff --git a/lib/types/thread-types.js b/lib/types/thread-types.js
--- a/lib/types/thread-types.js
+++ b/lib/types/thread-types.js
@@ -282,8 +282,6 @@
 };
 
 export type ChangeThreadSettingsResult = {
-  +threadInfo?: RawThreadInfo,
-  +threadInfos?: { +[id: string]: RawThreadInfo },
   +updatesResult: {
     +newUpdates: $ReadOnlyArray<ServerUpdateInfo>,
   },