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
@@ -10,7 +10,10 @@
   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 type { ThinRawThreadInfo } from 'lib/types/minimally-encoded-thread-permissions-types.js';
@@ -305,6 +308,10 @@
       web: 88,
     },
   );
+  const stripMemberPermissions = !hasMinCodeVersion(viewer.platformDetails, {
+    native: FUTURE_CODE_VERSION,
+    web: FUTURE_CODE_VERSION,
+  });
 
   const threadInfos: {
     [string]: LegacyThinRawThreadInfo | ThinRawThreadInfo,
@@ -324,6 +331,7 @@
         allowAddingUsersToCommunityRoot: addingUsersToCommunityRootSupported,
         filterManageFarcasterChannelTagsPermission:
           manageFarcasterChannelTagsPermissionUnsupported,
+        stripMemberPermissions: stripMemberPermissions,
       },
     );
     if (threadInfo) {
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
@@ -101,6 +101,10 @@
   type ThreadEntity,
   type UserEntity,
 } from '../utils/entity-text.js';
+import {
+  stripMemberPermissionsFromRawThreadInfo,
+  type ThinRawThreadInfoWithPermissions,
+} from '../utils/member-info-utils.js';
 import { entries, values } from '../utils/objects.js';
 import { useSelector } from '../utils/redux-utils.js';
 import { usingOlmViaTunnelbrokerForDMs } from '../utils/services-utils.js';
@@ -703,6 +707,7 @@
   +includeSpecialRoleFieldInRoles?: boolean,
   +allowAddingUsersToCommunityRoot?: boolean,
   +filterManageFarcasterChannelTagsPermission?: boolean,
+  +stripMemberPermissions?: boolean,
 };
 
 function rawThreadInfoFromServerThreadInfo(
@@ -724,6 +729,7 @@
     options?.allowAddingUsersToCommunityRoot;
   const filterManageFarcasterChannelTagsPermission =
     options?.filterManageFarcasterChannelTagsPermission;
+  const stripMemberPermissions = options?.stripMemberPermissions;
 
   const filterThreadPermissions = (
     innerThreadPermissions: ThreadPermissionsInfo,
@@ -859,27 +865,49 @@
     return rawThreadInfo;
   }
 
-  const minimallyEncoded =
+  const minimallyEncodedRawThreadInfoWithMemberPermissions =
     deprecatedMinimallyEncodeRawThreadInfo(rawThreadInfo);
-  invariant(!minimallyEncoded.thick, 'ServerThreadInfo should be thin thread');
+  invariant(
+    !minimallyEncodedRawThreadInfoWithMemberPermissions.thick,
+    'ServerThreadInfo should be thin thread',
+  );
   if (shouldIncludeSpecialRoleFieldInRoles) {
-    return minimallyEncoded;
+    return minimallyEncodedRawThreadInfoWithMemberPermissions;
   }
 
   const minimallyEncodedRolesWithoutSpecialRoleField = Object.fromEntries(
-    entries(minimallyEncoded.roles).map(([key, role]) => [
-      key,
-      {
-        ..._omit('specialRole')(role),
-        isDefault: roleIsDefaultRole(role),
-      },
-    ]),
+    entries(minimallyEncodedRawThreadInfoWithMemberPermissions.roles).map(
+      ([key, role]) => [
+        key,
+        {
+          ..._omit('specialRole')(role),
+          isDefault: roleIsDefaultRole(role),
+        },
+      ],
+    ),
   );
 
-  return {
-    ...minimallyEncoded,
-    roles: minimallyEncodedRolesWithoutSpecialRoleField,
-  };
+  if (!stripMemberPermissions) {
+    return {
+      ...minimallyEncodedRawThreadInfoWithMemberPermissions,
+      roles: minimallyEncodedRolesWithoutSpecialRoleField,
+    };
+  }
+
+  // The return value of `deprecatedMinimallyEncodeRawThreadInfo` is typed
+  // as `RawThreadInfo`, but still includes thread member permissions.
+  // This was to prevent introducing "Legacy" types that would need to be
+  // maintained going forward. This `any`-cast allows us to more precisely
+  // type the obj being passed to `stripMemberPermissionsFromRawThreadInfo`.
+  const rawThreadInfoWithMemberPermissions: ThinRawThreadInfoWithPermissions =
+    ({
+      ...minimallyEncodedRawThreadInfoWithMemberPermissions,
+      roles: minimallyEncodedRolesWithoutSpecialRoleField,
+    }: any);
+
+  return stripMemberPermissionsFromRawThreadInfo(
+    rawThreadInfoWithMemberPermissions,
+  );
 }
 
 function threadUIName(threadInfo: ThreadInfo): string | ThreadEntity {
diff --git a/lib/utils/member-info-utils.js b/lib/utils/member-info-utils.js
--- a/lib/utils/member-info-utils.js
+++ b/lib/utils/member-info-utils.js
@@ -1,11 +1,9 @@
 // @flow
 
-import invariant from 'invariant';
-
 import type {
   MemberInfoSansPermissions,
   MemberInfoWithPermissions,
-  RawThreadInfo,
+  ThinRawThreadInfo,
 } from '../types/minimally-encoded-thread-permissions-types.js';
 
 function stripPermissionsFromMemberInfo(
@@ -15,13 +13,14 @@
   return rest;
 }
 
+export type ThinRawThreadInfoWithPermissions = $ReadOnly<{
+  ...ThinRawThreadInfo,
+  +members: $ReadOnlyArray<MemberInfoWithPermissions>,
+}>;
+
 function stripMemberPermissionsFromRawThreadInfo(
-  rawThreadInfo: RawThreadInfo,
-): RawThreadInfo {
-  invariant(
-    !rawThreadInfo.thick,
-    'Expect ThinRawThreadInfo in stripMemberPermissionsFromRawThreadInfo',
-  );
+  rawThreadInfo: ThinRawThreadInfoWithPermissions,
+): ThinRawThreadInfo {
   return {
     ...rawThreadInfo,
     members: rawThreadInfo.members.map(stripPermissionsFromMemberInfo),