diff --git a/apps/client-asset-sg/src/app/i18n/de.ts b/apps/client-asset-sg/src/app/i18n/de.ts
index ab467b6a..1c45b2ac 100644
--- a/apps/client-asset-sg/src/app/i18n/de.ts
+++ b/apps/client-asset-sg/src/app/i18n/de.ts
@@ -124,6 +124,7 @@ export const deAppTranslations = {
         alternativeId: 'Alternativ-ID',
         alternativeIdDescription: 'Beschreibung Alternativ-ID',
         addNewAlternativeId: 'Neue Alternativ-ID hinzufügen',
+        referencesWarning: 'Um die Arbeitsgruppe zu ändern, müssen Sie erst alle Verweise entfernen.',
       },
       files: {
         tabName: 'Dateien',
diff --git a/apps/client-asset-sg/src/app/i18n/en.ts b/apps/client-asset-sg/src/app/i18n/en.ts
index 25516501..1b9194af 100644
--- a/apps/client-asset-sg/src/app/i18n/en.ts
+++ b/apps/client-asset-sg/src/app/i18n/en.ts
@@ -125,6 +125,7 @@ export const enAppTranslations: AppTranslations = {
         alternativeId: 'Alternative ID',
         alternativeIdDescription: 'Alternative ID Description',
         addNewAlternativeId: 'Add new alternative ID',
+        referencesWarning: 'In order to change the workgroup, you must first remove all references.',
       },
       files: {
         tabName: 'Files',
diff --git a/apps/client-asset-sg/src/app/i18n/fr.ts b/apps/client-asset-sg/src/app/i18n/fr.ts
index f758d055..4bee145e 100644
--- a/apps/client-asset-sg/src/app/i18n/fr.ts
+++ b/apps/client-asset-sg/src/app/i18n/fr.ts
@@ -126,6 +126,7 @@ export const frAppTranslations: AppTranslations = {
         alternativeId: 'ID alternative',
         alternativeIdDescription: "Description d'ID alternative",
         addNewAlternativeId: 'Ajouter une nouvelle ID alternative',
+        referencesWarning: 'Pour changer le groupe de travail, vous devez d’abord supprimer toutes les références.',
       },
       files: {
         tabName: 'Fichiers',
diff --git a/apps/client-asset-sg/src/app/i18n/it.ts b/apps/client-asset-sg/src/app/i18n/it.ts
index cd12fb43..5520d37b 100644
--- a/apps/client-asset-sg/src/app/i18n/it.ts
+++ b/apps/client-asset-sg/src/app/i18n/it.ts
@@ -125,6 +125,7 @@ export const itAppTranslations: AppTranslations = {
         alternativeId: 'IT Alternativ-ID',
         alternativeIdDescription: 'IT Beschreibung Alternativ-ID',
         addNewAlternativeId: 'IT Neue Alternativ-ID hinzufügen',
+        referencesWarning: 'IT Um die Arbeitsgruppe zu ändern, müssen Sie erst alle Verweise entfernen.',
       },
       files: {
         tabName: 'IT Dateien',
diff --git a/apps/client-asset-sg/src/app/i18n/rm.ts b/apps/client-asset-sg/src/app/i18n/rm.ts
index 45bfb3f9..7a678650 100644
--- a/apps/client-asset-sg/src/app/i18n/rm.ts
+++ b/apps/client-asset-sg/src/app/i18n/rm.ts
@@ -125,6 +125,7 @@ export const rmAppTranslations: AppTranslations = {
         alternativeId: 'RM Alternativ-ID',
         alternativeIdDescription: 'RM Beschreibung Alternativ-ID',
         addNewAlternativeId: 'RM Neue Alternativ-ID hinzufügen',
+        referencesWarning: 'RM Um die Arbeitsgruppe zu ändern, müssen Sie erst alle Verweise entfernen.',
       },
       files: {
         tabName: 'RM Dateien',
diff --git a/apps/server-asset-sg/src/app.module.ts b/apps/server-asset-sg/src/app.module.ts
index 2512ceb7..11aa94fb 100644
--- a/apps/server-asset-sg/src/app.module.ts
+++ b/apps/server-asset-sg/src/app.module.ts
@@ -11,6 +11,7 @@ import { JwtMiddleware } from '@/core/middleware/jwt.middleware';
 import { PrismaService } from '@/core/prisma.service';
 import { AssetEditController } from '@/features/asset-edit/asset-edit.controller';
 import { AssetEditRepo } from '@/features/asset-edit/asset-edit.repo';
+import { AssetEditService } from '@/features/asset-edit/asset-edit.service';
 import { AssetInfoRepo } from '@/features/assets/asset-info.repo';
 import { AssetRepo } from '@/features/assets/asset.repo';
 import { AssetsController } from '@/features/assets/assets.controller';
@@ -51,6 +52,7 @@ import { WorkgroupsController } from '@/features/workgroups/workgroups.controlle
     provideElasticsearch,
     AssetEditRepo,
     AssetInfoRepo,
+    AssetEditService,
     AssetRepo,
     AssetSearchService,
     AssetSyncService,
diff --git a/apps/server-asset-sg/src/features/asset-edit/asset-edit.controller.ts b/apps/server-asset-sg/src/features/asset-edit/asset-edit.controller.ts
index f505b30d..b283a68c 100644
--- a/apps/server-asset-sg/src/features/asset-edit/asset-edit.controller.ts
+++ b/apps/server-asset-sg/src/features/asset-edit/asset-edit.controller.ts
@@ -17,11 +17,16 @@ import { authorize } from '@/core/authorize';
 import { CurrentUser } from '@/core/decorators/current-user.decorator';
 import { ParseBody } from '@/core/decorators/parse.decorator';
 import { AssetEditRepo } from '@/features/asset-edit/asset-edit.repo';
+import { AssetEditService } from '@/features/asset-edit/asset-edit.service';
 import { AssetSearchService } from '@/features/assets/search/asset-search.service';
 
 @Controller('/asset-edit')
 export class AssetEditController {
-  constructor(private readonly assetEditRepo: AssetEditRepo, private readonly assetSearchService: AssetSearchService) {}
+  constructor(
+    private readonly assetEditRepo: AssetEditRepo,
+    private readonly assetEditService: AssetEditService,
+    private readonly assetSearchService: AssetSearchService
+  ) {}
 
   @Get('/:id')
   async show(@Param('id', ParseIntPipe) id: number, @CurrentUser() user: User): Promise<unknown> {
@@ -38,6 +43,8 @@ export class AssetEditController {
     authorize(AssetEditPolicy, user).canCreate();
     validatePatch(user, patch);
 
+    await this.assetEditService.validateReferencesOrThrow({ user, patch });
+
     const asset = await this.assetEditRepo.create({ user, patch });
     await this.assetSearchService.register(asset);
     return AssetEditDetail.encode(asset);
@@ -56,6 +63,7 @@ export class AssetEditController {
 
     authorize(AssetEditPolicy, user).canUpdate(record);
     validatePatch(user, patch, record);
+    await this.assetEditService.validateReferencesOrThrow({ user, patch }, id);
 
     const asset = await this.assetEditRepo.update(record.assetId, { user, patch });
     if (asset === null) {
diff --git a/apps/server-asset-sg/src/features/asset-edit/asset-edit.http b/apps/server-asset-sg/src/features/asset-edit/asset-edit.http
index c421a664..d6a9ac66 100644
--- a/apps/server-asset-sg/src/features/asset-edit/asset-edit.http
+++ b/apps/server-asset-sg/src/features/asset-edit/asset-edit.http
@@ -35,7 +35,8 @@ Content-Type: application/json
   "titleOriginal": "My Cool Asset",
   "titlePublic": "Our Cool Asset",
   "typeNatRels": [],
-  "workgroupId": 1
+  "workgroupId": 1,
+  "assetFiles": []
 }
 
 ### Update asset-edit
diff --git a/apps/server-asset-sg/src/features/asset-edit/asset-edit.repo.ts b/apps/server-asset-sg/src/features/asset-edit/asset-edit.repo.ts
index 8aa98832..bf14a32d 100644
--- a/apps/server-asset-sg/src/features/asset-edit/asset-edit.repo.ts
+++ b/apps/server-asset-sg/src/features/asset-edit/asset-edit.repo.ts
@@ -111,7 +111,6 @@ export class AssetEditRepo implements Repo<AssetEditDetail, number, AssetEditDat
     if (count === 0) {
       return null;
     }
-
     // Run the update in a transaction, as it consists of multiple prisma queries.
     // Note that all mutations within this transaction are no-ops if there is no asset for `id`.
     await this.prismaService.$transaction(async () => {
@@ -127,7 +126,7 @@ export class AssetEditRepo implements Repo<AssetEditDetail, number, AssetEditDat
           assetKindItemCode: data.patch.assetKindItemCode,
           assetFormatItemCode: data.patch.assetFormatItemCode,
           isNatRel: data.patch.isNatRel,
-          assetMainId: O.toUndefined(data.patch.assetMainId),
+          assetMainId: O.toNullable(data.patch.assetMainId),
           lastProcessedDate: new Date(),
           processor: data.user.email,
           manCatLabelRefs: {
diff --git a/apps/server-asset-sg/src/features/asset-edit/asset-edit.service.ts b/apps/server-asset-sg/src/features/asset-edit/asset-edit.service.ts
new file mode 100644
index 00000000..911d35b7
--- /dev/null
+++ b/apps/server-asset-sg/src/features/asset-edit/asset-edit.service.ts
@@ -0,0 +1,55 @@
+import { HttpException, HttpStatus, Injectable } from '@nestjs/common';
+import * as O from 'fp-ts/Option';
+
+import { AssetEditData } from './asset-edit.repo';
+import { PrismaService } from '@/core/prisma.service';
+
+@Injectable()
+export class AssetEditService {
+  constructor(private readonly prismaService: PrismaService) {}
+
+  public async validateReferencesOrThrow(data: AssetEditData, id?: number): Promise<void> {
+    // check if any of the siblings are in another workgroup
+    for (const assetYId of data.patch.siblingAssetIds) {
+      const siblingCandidate = await this.prismaService.asset.findUnique({
+        where: { assetId: assetYId },
+        select: { workgroupId: true },
+      });
+      if (siblingCandidate?.workgroupId !== data.patch.workgroupId) {
+        throw new HttpException(
+          'Sibling assets must be in the same workgroup as the edited asset',
+          HttpStatus.UNPROCESSABLE_ENTITY
+        );
+      }
+    }
+
+    // check if the parent asset is in another workgroup
+    const assetMainId = O.toUndefined(data.patch.assetMainId);
+    if (assetMainId) {
+      const assetMain = await this.prismaService.asset.findUnique({
+        where: { assetId: assetMainId },
+        select: { workgroupId: true },
+      });
+      if (assetMain?.workgroupId !== data.patch.workgroupId) {
+        throw new HttpException('Cannot assign parent asset from different workgroup', HttpStatus.UNPROCESSABLE_ENTITY);
+      }
+    }
+
+    // check if any of the subordinate assets are in another workgroup for exisiting assets
+    if (id) {
+      const childAssets = await this.prismaService.asset.findMany({
+        where: { assetMainId: id },
+        select: { workgroupId: true },
+      });
+
+      for (const child of childAssets) {
+        if (child.workgroupId !== data.patch.workgroupId) {
+          throw new HttpException(
+            'Child assets must be in the same workgroup as the parent asset',
+            HttpStatus.UNPROCESSABLE_ENTITY
+          );
+        }
+      }
+    }
+  }
+}
diff --git a/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.html b/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.html
index 8fe4db56..ef8e72f9 100644
--- a/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.html
+++ b/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.html
@@ -3,6 +3,10 @@
     <div class="flex flex-column form-column mr-8">
       <div class="flex flex-column bg-white mb-4 py-4 px-6 overflow-y-scroll">
         <div class="font-bold mb-4" translate>workgroup.title</div>
+        <div *ngIf="showWarningForReferences" class="flex mb-2 bg-orange-01 px-3 py-2">
+          <svg-icon key="warning-filled" class="mr-3"></svg-icon>
+          {{ "edit.tabs.general.referencesWarning" | translate }}
+        </div>
         <mat-form-field class="mb-2">
           <mat-label translate>workgroup.title</mat-label>
           <mat-select formControlName="workgroupId">
diff --git a/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.ts b/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.ts
index ee48b446..e62bc314 100644
--- a/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.ts
+++ b/libs/asset-editor/src/lib/components/asset-editor-tab-general/asset-editor-tab-general.component.ts
@@ -56,6 +56,8 @@ export class AssetEditorTabGeneralComponent implements OnInit {
     description: new FormControl<string>('', { nonNullable: true }),
   });
 
+  public showWarningForReferences = false;
+
   public readonly state: RxState<AssetEditorTabGeneralState> = inject(RxState<AssetEditorTabGeneralState>);
 
   public readonly _referenceDataVM$ = this.state.select('referenceDataVM');
@@ -174,6 +176,10 @@ export class AssetEditorTabGeneralComponent implements OnInit {
         this.idForm.patchValue({ idId, id, description });
       }
     });
+    this.setDisabledStatusOfWorkgroup();
+    this.rootFormGroup.controls.references.valueChanges.pipe(untilDestroyed(this)).subscribe(() => {
+      this.setDisabledStatusOfWorkgroup();
+    });
     this.ngOnInit$.next();
   }
 
@@ -222,5 +228,19 @@ export class AssetEditorTabGeneralComponent implements OnInit {
     this.idForm.patchValue({ id, description });
   }
 
+  private setDisabledStatusOfWorkgroup() {
+    if (
+      this.rootFormGroup.getRawValue().references.siblingAssets.length > 0 ||
+      this.rootFormGroup.getRawValue().references.childAssets.length > 0 ||
+      this.rootFormGroup.getRawValue().references.assetMain
+    ) {
+      this.form.controls.workgroupId.disable({ emitEvent: false });
+      this.showWarningForReferences = true;
+    } else {
+      this.form.controls.workgroupId.enable({ emitEvent: false });
+      this.showWarningForReferences = false;
+    }
+  }
+
   public eqAssetLanguageEdit = eqAssetLanguageEdit;
 }
diff --git a/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.html b/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.html
index e28879d1..f8c75875 100644
--- a/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.html
+++ b/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.html
@@ -41,9 +41,9 @@
         <mat-form-field>
           <mat-label>Typ</mat-label>
           <mat-select formControlName="assetReferenceType">
-            <mat-option *ngIf="!(_addParentDisabled$ | push)" value="parent">{{
-              "edit.tabs.references.referenceType.parent" | translate
-            }}</mat-option>
+            <mat-option *ngIf="!(_addParentDisabled$ | push)" value="parent"
+              >{{ "edit.tabs.references.referenceType.parent" | translate }}
+            </mat-option>
             <mat-option value="sibling">{{ "edit.tabs.references.referenceType.sibling" | translate }}</mat-option>
           </mat-select>
         </mat-form-field>
diff --git a/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.ts b/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.ts
index e0218657..aa928482 100644
--- a/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.ts
+++ b/libs/asset-editor/src/lib/components/asset-editor-tab-references/asset-editor-tab-references.component.ts
@@ -1,25 +1,25 @@
 import { HttpClient, HttpErrorResponse } from '@angular/common/http';
-import { ChangeDetectionStrategy, Component, ElementRef, OnInit, ViewChild, inject } from '@angular/core';
+import { ChangeDetectionStrategy, Component, ElementRef, inject, OnInit, ViewChild } from '@angular/core';
 import { FormBuilder, FormControl, FormGroupDirective, Validators } from '@angular/forms';
 import { MatAutocompleteSelectedEvent } from '@angular/material/autocomplete';
 import { httpErrorResponseError } from '@asset-sg/client-shared';
 import { unknownToUnknownError } from '@asset-sg/core';
-import { AssetByTitle, LinkedAsset } from '@asset-sg/shared';
+import { AssetByTitle, AssetEditDetail, LinkedAsset } from '@asset-sg/shared';
 import { UntilDestroy } from '@ngneat/until-destroy';
 import * as A from 'fp-ts/Array';
 import * as E from 'fp-ts/Either';
 import { flow, pipe } from 'fp-ts/function';
 import * as D from 'io-ts/Decoder';
 import {
-  Observable,
-  Subject,
   catchError,
   combineLatest,
   debounceTime,
   distinctUntilChanged,
   map,
+  Observable,
   of,
   startWith,
+  Subject,
   switchMap,
 } from 'rxjs';
 
@@ -79,19 +79,25 @@ export class AssetEditorTabReferencesComponent implements OnInit {
       this._authorSearchInput$.pipe(
         debounceTime(300),
         switchMap(
-          (value): Observable<LinkedAsset[]> =>
+          (value): Observable<AssetEditDetail[]> =>
             value.length >= 3
-              ? this._httpClient.get(`/api/asset-edit/search?title=${value}`).pipe(
-                  catchError((err: HttpErrorResponse | unknown) =>
-                    of(err instanceof HttpErrorResponse ? httpErrorResponseError(err) : unknownToUnknownError(err))
-                  ),
-                  map(
-                    flow(
-                      D.array(AssetByTitle).decode,
-                      E.getOrElseW(() => [])
+              ? this._httpClient
+                  .post(`/api/assets/search?limit=10`, {
+                    text: value,
+                    workgroupIds: [this.rootFormGroup.getRawValue().general.workgroupId],
+                  })
+                  .pipe(
+                    map((res) => (res as { data: AssetEditDetail[] }).data),
+                    catchError((err: HttpErrorResponse | unknown) =>
+                      of(err instanceof HttpErrorResponse ? httpErrorResponseError(err) : unknownToUnknownError(err))
+                    ),
+                    map(
+                      flow(
+                        D.array(AssetEditDetail).decode,
+                        E.getOrElseW(() => [])
+                      )
                     )
                   )
-                )
               : of([])
         )
       ),