diff --git a/keyserver/src/scripts/generate-converter-from-validator.js b/keyserver/src/scripts/generate-converter-from-validator.js
--- a/keyserver/src/scripts/generate-converter-from-validator.js
+++ b/keyserver/src/scripts/generate-converter-from-validator.js
@@ -7,7 +7,7 @@
   mediaValidator,
 } from 'lib/types/media-types.js';
 import { threadPermissionInfoValidator } from 'lib/types/thread-permission-types.js';
-import { legacyRawThreadInfoValidator } from 'lib/types/thread-types.js';
+import { legacyThinRawThreadInfoValidator } from 'lib/types/thread-types.js';
 import { ashoatKeyserverID, tID } from 'lib/utils/validation-utils.js';
 
 import { main } from './utils.js';
@@ -213,7 +213,7 @@
 }
 
 // Input arguments:
-const validator = legacyRawThreadInfoValidator;
+const validator = legacyThinRawThreadInfoValidator;
 const typeName = 'RawThreadInfo';
 const validatorToBeConverted = tID;
 const conversionExpressionString = (inputName: string) =>
diff --git a/keyserver/src/shared/state-sync/threads-state-sync-spec.js b/keyserver/src/shared/state-sync/threads-state-sync-spec.js
--- a/keyserver/src/shared/state-sync/threads-state-sync-spec.js
+++ b/keyserver/src/shared/state-sync/threads-state-sync-spec.js
@@ -1,6 +1,6 @@
 // @flow
 
-import { mixedRawThreadInfoValidator } from 'lib/permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from 'lib/permissions/minimally-encoded-raw-thread-info-validators.js';
 import { threadsStateSyncSpec as libSpec } from 'lib/shared/state-sync/threads-state-sync-spec.js';
 import type { RawThreadInfo } from 'lib/types/minimally-encoded-thread-permissions-types.js';
 import type { ClientThreadInconsistencyReportCreationRequest } from 'lib/types/report-types.js';
@@ -47,6 +47,10 @@
 }
 
 async function getServerInfoHash(info: LegacyRawThreadInfo | RawThreadInfo) {
-  const output = await validateOutput(null, mixedRawThreadInfoValidator, info);
+  const output = await validateOutput(
+    null,
+    mixedThinRawThreadInfoValidator,
+    info,
+  );
   return hash(output);
 }
diff --git a/lib/permissions/minimally-encoded-raw-thread-info-validators.js b/lib/permissions/minimally-encoded-raw-thread-info-validators.js
--- a/lib/permissions/minimally-encoded-raw-thread-info-validators.js
+++ b/lib/permissions/minimally-encoded-raw-thread-info-validators.js
@@ -10,18 +10,18 @@
 import type {
   MemberInfoWithPermissions,
   ThreadCurrentUserInfo,
-  RawThreadInfo,
+  ThinRawThreadInfo,
   RoleInfo,
   RoleInfoWithoutSpecialRole,
-  RawThreadInfoWithoutSpecialRole,
+  ThinRawThreadInfoWithoutSpecialRole,
   MinimallyEncodedThickMemberInfo,
   MemberInfoSansPermissions,
 } from '../types/minimally-encoded-thread-permissions-types.js';
 import { threadSubscriptionValidator } from '../types/subscription-types.js';
 import {
-  type LegacyRawThreadInfo,
+  type LegacyThinRawThreadInfo,
   legacyMemberInfoValidator,
-  legacyRawThreadInfoValidator,
+  legacyThinRawThreadInfoValidator,
   legacyThreadCurrentUserInfoValidator,
 } from '../types/thread-types.js';
 import { tBool, tID, tShape, tUserID } from '../utils/validation-utils.js';
@@ -90,9 +90,9 @@
     subscription: threadSubscriptionValidator,
   });
 
-const rawThreadInfoValidator: TInterface<RawThreadInfo> = tShape<RawThreadInfo>(
-  {
-    ...legacyRawThreadInfoValidator.meta.props,
+const thinRawThreadInfoValidator: TInterface<ThinRawThreadInfo> =
+  tShape<ThinRawThreadInfo>({
+    ...legacyThinRawThreadInfoValidator.meta.props,
     minimallyEncoded: tBool(true),
     members: t.union([
       t.list(memberInfoWithPermissionsValidator),
@@ -100,8 +100,7 @@
     ]),
     roles: t.dict(tID, roleInfoValidator),
     currentUser: threadCurrentUserInfoValidator,
-  },
-);
+  });
 
 const roleInfoWithoutSpecialRolesValidator: TInterface<RoleInfoWithoutSpecialRole> =
   tShape<RoleInfoWithoutSpecialRole>({
@@ -109,18 +108,20 @@
     isDefault: t.maybe(t.Boolean),
   });
 
-const rawThreadInfoWithoutSpecialRoles: TInterface<RawThreadInfoWithoutSpecialRole> =
-  tShape<RawThreadInfoWithoutSpecialRole>({
-    ...rawThreadInfoValidator.meta.props,
+const thinRawThreadInfoWithoutSpecialRolesValidator: TInterface<ThinRawThreadInfoWithoutSpecialRole> =
+  tShape<ThinRawThreadInfoWithoutSpecialRole>({
+    ...thinRawThreadInfoValidator.meta.props,
     roles: t.dict(tID, roleInfoWithoutSpecialRolesValidator),
   });
 
-const mixedRawThreadInfoValidator: TUnion<
-  LegacyRawThreadInfo | RawThreadInfo | RawThreadInfoWithoutSpecialRole,
+const mixedThinRawThreadInfoValidator: TUnion<
+  | LegacyThinRawThreadInfo
+  | ThinRawThreadInfo
+  | ThinRawThreadInfoWithoutSpecialRole,
 > = t.union([
-  legacyRawThreadInfoValidator,
-  rawThreadInfoValidator,
-  rawThreadInfoWithoutSpecialRoles,
+  legacyThinRawThreadInfoValidator,
+  thinRawThreadInfoValidator,
+  thinRawThreadInfoWithoutSpecialRolesValidator,
 ]);
 
 export {
@@ -130,6 +131,6 @@
   roleInfoValidator,
   persistedRoleInfoValidator,
   threadCurrentUserInfoValidator,
-  rawThreadInfoValidator,
-  mixedRawThreadInfoValidator,
+  thinRawThreadInfoValidator,
+  mixedThinRawThreadInfoValidator,
 };
diff --git a/lib/permissions/minimally-encoded-thread-permissions.test.js b/lib/permissions/minimally-encoded-thread-permissions.test.js
--- a/lib/permissions/minimally-encoded-thread-permissions.test.js
+++ b/lib/permissions/minimally-encoded-thread-permissions.test.js
@@ -3,7 +3,7 @@
 import {
   memberInfoWithPermissionsValidator,
   persistedRoleInfoValidator,
-  rawThreadInfoValidator,
+  thinRawThreadInfoValidator,
   roleInfoValidator,
   threadCurrentUserInfoValidator,
 } from './minimally-encoded-raw-thread-info-validators.js';
@@ -513,7 +513,7 @@
 describe('minimallyEncodedRawThreadInfoValidator', () => {
   it('should validate correctly formed MinimallyEncodedRawThreadInfo', () => {
     expect(
-      rawThreadInfoValidator.is(exampleMinimallyEncodedRawThreadInfoA),
+      thinRawThreadInfoValidator.is(exampleMinimallyEncodedRawThreadInfoA),
     ).toBe(true);
   });
 });
@@ -521,7 +521,7 @@
 describe('minimallyEncodeRawThreadInfo', () => {
   it('should correctly encode RawThreadInfo', () => {
     expect(
-      rawThreadInfoValidator.is(
+      thinRawThreadInfoValidator.is(
         minimallyEncodeRawThreadInfoWithMemberPermissions(
           exampleRawThreadInfoA,
         ),
diff --git a/lib/shared/updates/join-thread-spec.js b/lib/shared/updates/join-thread-spec.js
--- a/lib/shared/updates/join-thread-spec.js
+++ b/lib/shared/updates/join-thread-spec.js
@@ -5,7 +5,7 @@
 import t from 'tcomb';
 
 import type { UpdateInfoFromRawInfoParams, UpdateSpec } from './update-spec.js';
-import { mixedRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
 import {
   type RawEntryInfo,
   rawEntryInfoValidator,
@@ -173,7 +173,7 @@
     type: tNumber(updateTypes.JOIN_THREAD),
     id: t.String,
     time: t.Number,
-    threadInfo: mixedRawThreadInfoValidator,
+    threadInfo: mixedThinRawThreadInfoValidator,
     rawMessageInfos: t.list(rawMessageInfoValidator),
     truncationStatus: messageTruncationStatusValidator,
     rawEntryInfos: t.list(rawEntryInfoValidator),
diff --git a/lib/shared/updates/update-thread-spec.js b/lib/shared/updates/update-thread-spec.js
--- a/lib/shared/updates/update-thread-spec.js
+++ b/lib/shared/updates/update-thread-spec.js
@@ -5,7 +5,7 @@
 import t from 'tcomb';
 
 import type { UpdateInfoFromRawInfoParams, UpdateSpec } from './update-spec.js';
-import { mixedRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
 import type { RawThreadInfos } from '../../types/thread-types.js';
 import { updateTypes } from '../../types/update-types-enum.js';
 import type {
@@ -117,7 +117,7 @@
     type: tNumber(updateTypes.UPDATE_THREAD),
     id: t.String,
     time: t.Number,
-    threadInfo: mixedRawThreadInfoValidator,
+    threadInfo: mixedThinRawThreadInfoValidator,
   }),
   getUpdatedThreadInfo(update: ThreadUpdateInfo) {
     return update.threadInfo;
diff --git a/lib/types/minimally-encoded-thread-permissions-types.js b/lib/types/minimally-encoded-thread-permissions-types.js
--- a/lib/types/minimally-encoded-thread-permissions-types.js
+++ b/lib/types/minimally-encoded-thread-permissions-types.js
@@ -242,8 +242,8 @@
   +isDefault?: boolean,
 }>;
 
-export type RawThreadInfoWithoutSpecialRole = $ReadOnly<{
-  ...RawThreadInfo,
+export type ThinRawThreadInfoWithoutSpecialRole = $ReadOnly<{
+  ...ThinRawThreadInfo,
   +roles: { +[id: string]: RoleInfoWithoutSpecialRole },
 }>;
 
diff --git a/lib/types/request-types.js b/lib/types/request-types.js
--- a/lib/types/request-types.js
+++ b/lib/types/request-types.js
@@ -32,7 +32,7 @@
   type AccountUserInfo,
   accountUserInfoValidator,
 } from './user-types.js';
-import { mixedRawThreadInfoValidator } from '../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../permissions/minimally-encoded-raw-thread-info-validators.js';
 import {
   tNumber,
   tShape,
@@ -164,7 +164,7 @@
     ),
     stateChanges: t.maybe(
       tShape<StateChanges>({
-        rawThreadInfos: t.maybe(t.list(mixedRawThreadInfoValidator)),
+        rawThreadInfos: t.maybe(t.list(mixedThinRawThreadInfoValidator)),
         rawEntryInfos: t.maybe(t.list(rawEntryInfoValidator)),
         currentUserInfo: t.maybe(currentUserInfoValidator),
         userInfos: t.maybe(t.list(accountUserInfoValidator)),
diff --git a/lib/types/socket-types.js b/lib/types/socket-types.js
--- a/lib/types/socket-types.js
+++ b/lib/types/socket-types.js
@@ -54,7 +54,7 @@
   type LoggedOutUserInfo,
   loggedOutUserInfoValidator,
 } from './user-types.js';
-import { mixedRawThreadInfoValidator } from '../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../permissions/minimally-encoded-raw-thread-info-validators.js';
 import { values } from '../utils/objects.js';
 import { tShape, tNumber, tID } from '../utils/validation-utils.js';
 
@@ -224,7 +224,7 @@
 }>;
 const serverFullStateSyncValidator = tShape<ServerFullStateSync>({
   ...baseFullStateSyncValidator.meta.props,
-  threadInfos: t.dict(tID, mixedRawThreadInfoValidator),
+  threadInfos: t.dict(tID, mixedThinRawThreadInfoValidator),
   currentUserInfo: currentUserInfoValidator,
 });
 
diff --git a/lib/types/thread-types-enum.js b/lib/types/thread-types-enum.js
--- a/lib/types/thread-types-enum.js
+++ b/lib/types/thread-types-enum.js
@@ -97,6 +97,10 @@
   return threadType;
 }
 
+export const thinThreadTypeValidator: TRefinement<number> = tNumEnum(
+  values(thinThreadTypes),
+);
+
 export function assertThickThreadType(threadType: number): ThickThreadType {
   invariant(
     threadType === 13 ||
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
@@ -34,7 +34,7 @@
 import {
   type ThinThreadType,
   type ThickThreadType,
-  threadTypeValidator,
+  thinThreadTypeValidator,
 } from './thread-types-enum.js';
 import type { ClientUpdateInfo, ServerUpdateInfo } from './update-types.js';
 import type { UserInfo, UserInfos } from './user-types.js';
@@ -180,10 +180,10 @@
 export type LegacyRawThreadInfos = {
   +[id: string]: LegacyRawThreadInfo,
 };
-export const legacyRawThreadInfoValidator: TInterface<LegacyRawThreadInfo> =
-  tShape<LegacyRawThreadInfo>({
+export const legacyThinRawThreadInfoValidator: TInterface<LegacyThinRawThreadInfo> =
+  tShape<LegacyThinRawThreadInfo>({
     id: tID,
-    type: threadTypeValidator,
+    type: thinThreadTypeValidator,
     name: t.maybe(t.String),
     avatar: t.maybe(clientAvatarValidator),
     description: t.maybe(t.String),
diff --git a/lib/types/validation.test.js b/lib/types/validation.test.js
--- a/lib/types/validation.test.js
+++ b/lib/types/validation.test.js
@@ -22,7 +22,7 @@
   serverUpdatesServerSocketMessageValidator,
 } from './socket-types.js';
 import { threadTypes } from './thread-types-enum.js';
-import { legacyRawThreadInfoValidator } from './thread-types.js';
+import { legacyThinRawThreadInfoValidator } from './thread-types.js';
 import { updateTypes } from './update-types-enum.js';
 import { messageSpecs } from '../shared/messages/message-specs.js';
 import { updateSpecs } from '../shared/updates/update-specs.js';
@@ -633,11 +633,14 @@
 
 describe('thread validation', () => {
   it('should validate correct thread', () => {
-    expect(legacyRawThreadInfoValidator.is(thread)).toBe(true);
+    expect(legacyThinRawThreadInfoValidator.is(thread)).toBe(true);
   });
   it('should not validate incorrect thread', () => {
     expect(
-      legacyRawThreadInfoValidator.is({ ...thread, creationTime: undefined }),
+      legacyThinRawThreadInfoValidator.is({
+        ...thread,
+        creationTime: undefined,
+      }),
     ).toBe(false);
   });
 });
diff --git a/lib/types/validators/redux-state-validators.js b/lib/types/validators/redux-state-validators.js
--- a/lib/types/validators/redux-state-validators.js
+++ b/lib/types/validators/redux-state-validators.js
@@ -2,7 +2,7 @@
 
 import t, { type TInterface } from 'tcomb';
 
-import { mixedRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
 import { tShape, tID } from '../../utils/validation-utils.js';
 import { entryStoreValidator } from '../entry-types.js';
 import { inviteLinksStoreValidator } from '../link-types.js';
@@ -22,7 +22,7 @@
 
 export const threadStoreValidator: TInterface<ThreadStore> =
   tShape<ThreadStore>({
-    threadInfos: t.dict(tID, mixedRawThreadInfoValidator),
+    threadInfos: t.dict(tID, mixedThinRawThreadInfoValidator),
   });
 
 export const initialReduxStateValidator: TInterface<ServerWebInitialReduxStateResponse> =
diff --git a/lib/types/validators/thread-validators.js b/lib/types/validators/thread-validators.js
--- a/lib/types/validators/thread-validators.js
+++ b/lib/types/validators/thread-validators.js
@@ -3,7 +3,7 @@
 import t from 'tcomb';
 import type { TInterface } from 'tcomb';
 
-import { mixedRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
 import { tShape, tID } from '../../utils/validation-utils.js';
 import { mediaValidator } from '../media-types.js';
 import {
@@ -69,7 +69,7 @@
 
 export const roleModificationResultValidator: TInterface<RoleModificationResult> =
   tShape<RoleModificationResult>({
-    threadInfo: t.maybe(mixedRawThreadInfoValidator),
+    threadInfo: t.maybe(mixedThinRawThreadInfoValidator),
     updatesResult: tShape({
       newUpdates: t.list(serverUpdateInfoValidator),
     }),
@@ -77,7 +77,7 @@
 
 export const roleDeletionResultValidator: TInterface<RoleDeletionResult> =
   tShape<RoleDeletionResult>({
-    threadInfo: t.maybe(mixedRawThreadInfoValidator),
+    threadInfo: t.maybe(mixedThinRawThreadInfoValidator),
     updatesResult: tShape({
       newUpdates: t.list(serverUpdateInfoValidator),
     }),
diff --git a/lib/types/validators/user-validators.js b/lib/types/validators/user-validators.js
--- a/lib/types/validators/user-validators.js
+++ b/lib/types/validators/user-validators.js
@@ -3,7 +3,7 @@
 import t, { type TInterface, type TUnion, type TEnums } from 'tcomb';
 
 import { policyTypeValidator } from '../../facts/policies.js';
-import { mixedRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../../permissions/minimally-encoded-raw-thread-info-validators.js';
 import { tShape, tID, tUserID } from '../../utils/validation-utils.js';
 import type {
   LogOutResponse,
@@ -38,7 +38,7 @@
     rawMessageInfos: t.list(rawMessageInfoValidator),
     currentUserInfo: loggedInUserInfoValidator,
     cookieChange: tShape({
-      threadInfos: t.dict(tID, mixedRawThreadInfoValidator),
+      threadInfos: t.dict(tID, mixedThinRawThreadInfoValidator),
       userInfos: t.list(userInfoValidator),
     }),
   });
@@ -57,7 +57,7 @@
     rawEntryInfos: t.maybe(t.list(rawEntryInfoValidator)),
     serverTime: t.Number,
     cookieChange: tShape({
-      threadInfos: t.dict(tID, mixedRawThreadInfoValidator),
+      threadInfos: t.dict(tID, mixedThinRawThreadInfoValidator),
       userInfos: t.list(userInfoValidator),
     }),
     notAcknowledgedPolicies: t.maybe(t.list<TEnums>(policyTypeValidator)),
diff --git a/lib/utils/user-info-extraction-utils.js b/lib/utils/user-info-extraction-utils.js
--- a/lib/utils/user-info-extraction-utils.js
+++ b/lib/utils/user-info-extraction-utils.js
@@ -5,7 +5,7 @@
 
 import { processNewUserIDsActionType } from '../actions/user-actions.js';
 import type { CallSingleKeyserverEndpointResponse } from '../keyserver-conn/call-single-keyserver-endpoint.js';
-import { mixedRawThreadInfoValidator } from '../permissions/minimally-encoded-raw-thread-info-validators.js';
+import { mixedThinRawThreadInfoValidator } from '../permissions/minimally-encoded-raw-thread-info-validators.js';
 import type { Endpoint } from '../types/endpoints.js';
 import type { Dispatch } from '../types/redux-types.js';
 import type { MixedRawThreadInfos } from '../types/thread-types.js';
@@ -33,7 +33,7 @@
 const additionalResponseFieldsValidator = tShape<AdditionalResponseFields>({
   cookieChange: t.maybe(
     tShape<AdditionalCookieChange>({
-      threadInfos: t.dict(tID, mixedRawThreadInfoValidator),
+      threadInfos: t.dict(tID, mixedThinRawThreadInfoValidator),
       userInfos: t.list(userInfoValidator),
       cookieInvalidated: t.maybe(t.Boolean),
       sessionID: t.maybe(t.String),