diff --git a/keyserver/src/fetchers/thread-fetchers.js b/keyserver/src/fetchers/thread-fetchers.js
--- a/keyserver/src/fetchers/thread-fetchers.js
+++ b/keyserver/src/fetchers/thread-fetchers.js
@@ -9,14 +9,17 @@
   getContainingThreadID,
   getCommunity,
 } from 'lib/shared/thread-utils.js';
-import { hasMinCodeVersion } from 'lib/shared/version-utils.js';
+import {
+  FUTURE_CODE_VERSION,
+  hasMinCodeVersion,
+} from 'lib/shared/version-utils.js';
 import type { AvatarDBContent, ClientAvatar } from 'lib/types/avatar-types.js';
 import type { RawMessageInfo, MessageInfo } from 'lib/types/message-types.js';
 import { threadTypes, type ThreadType } from 'lib/types/thread-types-enum.js';
 import {
-  type LegacyRawThreadInfos,
   type ServerThreadInfo,
-  type LegacyRawThreadInfo,
+  type RawThreadInfos,
+  type RawThreadInfo,
 } from 'lib/types/thread-types.js';
 import { ServerError } from 'lib/utils/errors.js';
 
@@ -245,7 +248,7 @@
 }
 
 export type FetchThreadInfosResult = {
-  +threadInfos: LegacyRawThreadInfos,
+  +threadInfos: RawThreadInfos,
 };
 
 async function fetchThreadInfos(
@@ -277,8 +280,12 @@
   const codeVersionBelow283 = !hasMinCodeVersion(viewer.platformDetails, {
     native: 285,
   });
+  const minimallyEncodedPermissionsSupported = hasMinCodeVersion(
+    viewer.platformDetails,
+    { native: FUTURE_CODE_VERSION },
+  );
 
-  const threadInfos: { [string]: LegacyRawThreadInfo } = {};
+  const threadInfos: { [string]: RawThreadInfo } = {};
   for (const threadID in serverResult.threadInfos) {
     const serverThreadInfo = serverResult.threadInfos[threadID];
     const threadInfo = rawThreadInfoFromServerThreadInfo(
@@ -289,6 +296,7 @@
         excludePinInfo: codeVersionBelow209,
         filterManageInviteLinksPermission: codeVersionBelow221,
         filterVoicedInAnnouncementChannelsPermission: codeVersionBelow283,
+        minimallyEncodePermissions: minimallyEncodedPermissionsSupported,
       },
     );
     if (threadInfo) {
diff --git a/keyserver/src/responders/user-responders.js b/keyserver/src/responders/user-responders.js
--- a/keyserver/src/responders/user-responders.js
+++ b/keyserver/src/responders/user-responders.js
@@ -11,6 +11,7 @@
   policies,
   policyTypeValidator,
 } from 'lib/facts/policies.js';
+import { rawThreadInfoValidator } from 'lib/permissions/minimally-encoded-thread-permissions-validators.js';
 import { hasMinCodeVersion } from 'lib/shared/version-utils.js';
 import type {
   ResetPasswordRequest,
@@ -437,7 +438,7 @@
     rawEntryInfos: t.maybe(t.list(rawEntryInfoValidator)),
     serverTime: t.Number,
     cookieChange: tShape({
-      threadInfos: t.dict(tID, legacyRawThreadInfoValidator),
+      threadInfos: t.dict(tID, rawThreadInfoValidator),
       userInfos: t.list(userInfoValidator),
     }),
     notAcknowledgedPolicies: t.maybe(t.list<TEnums>(policyTypeValidator)),
diff --git a/lib/shared/thread-utils.js b/lib/shared/thread-utils.js
--- a/lib/shared/thread-utils.js
+++ b/lib/shared/thread-utils.js
@@ -65,6 +65,7 @@
 } from '../types/minimally-encoded-thread-permissions-types.js';
 import {
   decodeMinimallyEncodedRoleInfo,
+  minimallyEncodeRawThreadInfo,
   minimallyEncodeThreadInfo,
 } from '../types/minimally-encoded-thread-permissions-types.js';
 import { userRelationshipStatus } from '../types/relationship-types.js';
@@ -736,12 +737,13 @@
   +excludePinInfo?: boolean,
   +filterManageInviteLinksPermission?: boolean,
   +filterVoicedInAnnouncementChannelsPermission?: boolean,
+  +minimallyEncodePermissions?: boolean,
 };
 function rawThreadInfoFromServerThreadInfo(
   serverThreadInfo: ServerThreadInfo,
   viewerID: string,
   options?: RawThreadInfoOptions,
-): ?LegacyRawThreadInfo {
+): ?RawThreadInfo {
   const filterThreadEditAvatarPermission =
     options?.filterThreadEditAvatarPermission;
   const excludePinInfo = options?.excludePinInfo;
@@ -749,6 +751,7 @@
     options?.filterManageInviteLinksPermission;
   const filterVoicedInAnnouncementChannelsPermission =
     options?.filterVoicedInAnnouncementChannelsPermission;
+  const shouldMinimallyEncodePermissions = options?.minimallyEncodePermissions;
 
   const filterThreadPermissions = _omitBy(
     (v, k) =>
@@ -853,12 +856,14 @@
     rawThreadInfo = { ...rawThreadInfo, avatar: serverThreadInfo.avatar };
   }
   if (!excludePinInfo) {
-    return {
+    rawThreadInfo = {
       ...rawThreadInfo,
       pinnedCount: serverThreadInfo.pinnedCount,
     };
   }
-  return rawThreadInfo;
+  return shouldMinimallyEncodePermissions
+    ? minimallyEncodeRawThreadInfo(rawThreadInfo)
+    : rawThreadInfo;
 }
 
 function threadUIName(threadInfo: ThreadInfo): string | ThreadEntity {