diff --git a/app/Services/Web/CategoryPageData.php b/app/Services/Web/CategoryPageData.php
index b1b93bfd..0c641f38 100644
--- a/app/Services/Web/CategoryPageData.php
+++ b/app/Services/Web/CategoryPageData.php
@@ -61,6 +61,13 @@ class CategoryPageData
             abort(404);
         }
 
+        // SEO/hreflang: lokalisierte Slugs beider Sprachen — die geladene
+        // translations-Relation ist auf die aktuelle Sprache gefiltert.
+        $alternateSlugs = $category->translations()
+            ->whereIn('locale', ['de', 'en'])
+            ->pluck('slug', 'locale')
+            ->all();
+
         $childCategories = Category::query()
             ->where('parent_id', $category->id)
             ->where('is_active', true)
@@ -278,6 +285,7 @@ class CategoryPageData
 
         return [
             'category' => $category,
+            'categoryAlternateSlugs' => $alternateSlugs,
             'referenceNow' => $referenceNow,
             'leadRelease' => $leadRelease,
             'topReleases' => $topReleases,
diff --git a/resources/views/components/web/structured-data.blade.php b/resources/views/components/web/structured-data.blade.php
new file mode 100644
index 00000000..92dbaebf
--- /dev/null
+++ b/resources/views/components/web/structured-data.blade.php
@@ -0,0 +1,5 @@
+@props(['data'])
+
+{{-- JSON_HEX_TAG escapet "<"/">" (<…), damit ein "</script>" im Inhalt
+     das Script-Tag nicht aufbrechen kann (XSS über Titel/Teaser). --}}
+<script type="application/ld+json">{!! json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_HEX_TAG) !!}</script>
diff --git a/resources/views/web/businessportal24.blade.php b/resources/views/web/businessportal24.blade.php
index 0e211591..14e8313c 100644
--- a/resources/views/web/businessportal24.blade.php
+++ b/resources/views/web/businessportal24.blade.php
@@ -2,8 +2,41 @@
 
 @php
     $brand = config('domains.domains.businessportal24.brand', []);
+
+    // SEO: WebSite-Markup mit Sitelinks-Searchbox (SearchAction auf /suche).
+    $portalBase = rtrim($domainUrl ?? config('app.url'), '/');
+    $brandFullName = ($brand['name'] ?? 'businessportal').($brand['accent'] ?? '24');
+
+    $jsonLd = [
+        '@context' => 'https://schema.org',
+        '@graph' => [
+            [
+                '@type' => 'WebSite',
+                'name' => $brandFullName,
+                'url' => $portalBase.'/',
+                'inLanguage' => app()->getLocale(),
+                'potentialAction' => [
+                    '@type' => 'SearchAction',
+                    'target' => [
+                        '@type' => 'EntryPoint',
+                        'urlTemplate' => $portalBase.'/'.app()->getLocale().'/suche?q={search_term_string}',
+                    ],
+                    'query-input' => 'required name=search_term_string',
+                ],
+            ],
+            [
+                '@type' => 'Organization',
+                'name' => $brandFullName,
+                'url' => $portalBase.'/',
+            ],
+        ],
+    ];
 @endphp
 
+@section('structured_data')
+    <x-web.structured-data :data="$jsonLd" />
+@endsection
+
 {{-- DE-Meta kommt brand-spezifisch aus config/domains.php, EN aus den Übersetzungsdateien. --}}
 @section('title', app()->getLocale() === 'de'
     ? ($brand['meta_title'] ?? 'Aktuelle Pressemitteilungen aus der deutschen Wirtschaft – businessportal24')
diff --git a/resources/views/web/kategorie.blade.php b/resources/views/web/kategorie.blade.php
index e80ab19c..20ae1554 100644
--- a/resources/views/web/kategorie.blade.php
+++ b/resources/views/web/kategorie.blade.php
@@ -30,11 +30,52 @@
         ? (filled($leadRelease->subtitle) ? $leadRelease->subtitle : $leadRelease->teaserText(220))
         : null;
     $leadReadTime = $leadRelease?->readTimeMinutes() ?? 1;
+
+    // SEO: hreflang über die lokalisierten Kategorie-Slugs (nur wenn beide
+    // Übersetzungen existieren — sonst würden wir auf 404s verweisen).
+    // Fallback [] deckt gecachte Page-Data von vor diesem Feld ab.
+    $alternateSlugs = $categoryAlternateSlugs ?? [];
+    $catSlugDe = $alternateSlugs['de'] ?? null;
+    $catSlugEn = $alternateSlugs['en'] ?? null;
+
+    // URLs aus der Portal-Basis (wie der Canonical im Layout) statt route(),
+    // damit Host und Canonical auch bei forceRootUrl-Abweichungen übereinstimmen.
+    $portalBase = rtrim($domainUrl ?? config('app.url'), '/');
+    $brandLabel = config('app.theme') === 'presseecho' ? 'presseecho' : 'businessportal24';
+
+    $breadcrumbs = collect([
+        ['name' => $brandLabel, 'item' => $portalBase.'/'.app()->getLocale()],
+        $parentName && $parentTranslation?->slug ? ['name' => $parentName, 'item' => $portalBase.'/'.app()->getLocale().'/category/'.$parentTranslation->slug] : null,
+        $catSlug ? ['name' => $catName, 'item' => $portalBase.'/'.app()->getLocale().'/category/'.$catSlug] : null,
+    ])->filter()->values();
+
+    $jsonLd = [
+        '@context' => 'https://schema.org',
+        '@type' => 'BreadcrumbList',
+        'itemListElement' => $breadcrumbs->map(fn (array $crumb, int $index) => [
+            '@type' => 'ListItem',
+            'position' => $index + 1,
+            'name' => $crumb['name'],
+            'item' => $crumb['item'],
+        ])->all(),
+    ];
 @endphp
 
 @section('title', __('web.category.meta_title', ['category' => $catName, 'brand' => config('app.name')]))
 @section('meta_description', Str::limit(strip_tags($catDescription), 155))
 
+@if ($catSlugDe && $catSlugEn)
+    @section('hreflang')
+        <link rel="alternate" hreflang="de" href="{{ $portalBase }}/de/category/{{ $catSlugDe }}">
+        <link rel="alternate" hreflang="en" href="{{ $portalBase }}/en/category/{{ $catSlugEn }}">
+        <link rel="alternate" hreflang="x-default" href="{{ $portalBase }}/de/category/{{ $catSlugDe }}">
+    @endsection
+@endif
+
+@section('structured_data')
+    <x-web.structured-data :data="$jsonLd" />
+@endsection
+
 @section('content')
     <x-web.site-header />
 
diff --git a/resources/views/web/layouts/web-master.blade.php b/resources/views/web/layouts/web-master.blade.php
index 9873dd22..bd0a9e16 100644
--- a/resources/views/web/layouts/web-master.blade.php
+++ b/resources/views/web/layouts/web-master.blade.php
@@ -49,12 +49,22 @@
     <meta property="og:title" content="{{ $pageTitle }}">
     <meta property="og:description" content="{{ $pageDescription }}">
     <meta property="og:url" content="{{ $canonicalUrl }}">
+    <meta property="og:locale" content="{{ app()->getLocale() === 'de' ? 'de_DE' : 'en_US' }}">
     @if ($ogImage)
         <meta property="og:image" content="{{ $ogImage }}">
     @endif
     <meta name="twitter:card" content="{{ $ogImage ? 'summary_large_image' : 'summary' }}">
     <meta name="twitter:title" content="{{ $pageTitle }}">
     <meta name="twitter:description" content="{{ $pageDescription }}">
+    @if ($ogImage)
+        <meta name="twitter:image" content="{{ $ogImage }}">
+    @endif
+
+    {{-- Seitenspezifische Zusatz-Metas (z. B. article:* auf PM-Detailseiten) --}}
+    @yield('meta_extra')
+
+    {{-- Strukturierte Daten (JSON-LD) – pro Seite optional gesetzt --}}
+    @yield('structured_data')
 
     <!-- Domain-spezifisches Favicon -->
     <link rel="icon" href="{{ asset(\App\Helpers\ThemeHelper::getFaviconPath()) }}">
diff --git a/resources/views/web/newsroom.blade.php b/resources/views/web/newsroom.blade.php
index 96226785..e66756df 100644
--- a/resources/views/web/newsroom.blade.php
+++ b/resources/views/web/newsroom.blade.php
@@ -30,6 +30,20 @@
         ? (filled($leadRelease->subtitle) ? $leadRelease->subtitle : $leadRelease->teaserText(220))
         : null;
     $leadReadTime = $leadRelease?->readTimeMinutes() ?? 1;
+
+    // SEO: Der Newsroom ist die kanonische Firmenseite im Portal —
+    // Organization-Markup verknüpft PMs (author) mit diesem Profil.
+    // Portal-Basis wie beim Canonical im Layout (unabhängig von forceRootUrl).
+    $newsroomUrl = rtrim($domainUrl ?? config('app.url'), '/').'/'.app()->getLocale().'/newsroom/'.$company->slug;
+    $jsonLd = [
+        '@context' => 'https://schema.org',
+        '@type' => 'Organization',
+        'name' => $company->name,
+        'url' => $newsroomUrl,
+        ...(filled($company->website) ? ['sameAs' => [$company->website]] : []),
+        ...($logoUrl ? ['logo' => $logoUrl] : []),
+        ...($boilerplate ? ['description' => Str::limit($boilerplate, 300)] : []),
+    ];
 @endphp
 
 @section('title', $company->name.' – Newsroom · '.$brandName.$brandAccent)
@@ -42,6 +56,10 @@
     <link rel="alternate" hreflang="x-default" href="{{ url('/de/newsroom/'.$company->slug) }}">
 @endsection
 
+@section('structured_data')
+    <x-web.structured-data :data="$jsonLd" />
+@endsection
+
 @section('content')
     <x-web.site-header />
 
diff --git a/resources/views/web/presseecho.blade.php b/resources/views/web/presseecho.blade.php
index d617edc1..144ee8c8 100644
--- a/resources/views/web/presseecho.blade.php
+++ b/resources/views/web/presseecho.blade.php
@@ -2,8 +2,41 @@
 
 @php
     $brand = config('domains.domains.presseecho.brand', []);
+
+    // SEO: WebSite-Markup mit Sitelinks-Searchbox (SearchAction auf /suche).
+    $portalBase = rtrim($domainUrl ?? config('app.url'), '/');
+    $brandFullName = ($brand['name'] ?? 'presse').($brand['accent'] ?? 'echo');
+
+    $jsonLd = [
+        '@context' => 'https://schema.org',
+        '@graph' => [
+            [
+                '@type' => 'WebSite',
+                'name' => $brandFullName,
+                'url' => $portalBase.'/',
+                'inLanguage' => app()->getLocale(),
+                'potentialAction' => [
+                    '@type' => 'SearchAction',
+                    'target' => [
+                        '@type' => 'EntryPoint',
+                        'urlTemplate' => $portalBase.'/'.app()->getLocale().'/suche?q={search_term_string}',
+                    ],
+                    'query-input' => 'required name=search_term_string',
+                ],
+            ],
+            [
+                '@type' => 'Organization',
+                'name' => $brandFullName,
+                'url' => $portalBase.'/',
+            ],
+        ],
+    ];
 @endphp
 
+@section('structured_data')
+    <x-web.structured-data :data="$jsonLd" />
+@endsection
+
 {{-- DE-Meta kommt brand-spezifisch aus config/domains.php, EN aus den Übersetzungsdateien. --}}
 @section('title', app()->getLocale() === 'de'
     ? ($brand['meta_title'] ?? 'Aktuelle Pressemitteilungen aus Wirtschaft & Industrie – presseecho')
diff --git a/resources/views/web/release-detail.blade.php b/resources/views/web/release-detail.blade.php
index c39128b2..394a1da9 100644
--- a/resources/views/web/release-detail.blade.php
+++ b/resources/views/web/release-detail.blade.php
@@ -83,6 +83,63 @@
     // URL existiert vor der Veröffentlichung noch nicht.
     $shareUrl = $isPreview ? request()->fullUrl() : route('release.detail', ['slug' => $release->slug]);
     $brandLabel = config('app.theme') === 'presseecho' ? 'presseecho' : 'businessportal24';
+
+    // SEO: NewsArticle + BreadcrumbList als JSON-LD — nur für die öffentliche
+    // Seite (die Vorschau ist noindex und hat keine stabile URL).
+    $jsonLd = null;
+
+    if (! $isPreview) {
+        $portalBase = rtrim($domainUrl ?? config('app.url'), '/');
+
+        // dateModified darf laut Google nicht vor datePublished liegen
+        // (updated_at kann bei terminierten PMs älter sein als published_at).
+        $modifiedAt = $release->updated_at?->greaterThan($publishedAt ?? $release->updated_at)
+            ? $release->updated_at
+            : $publishedAt;
+
+        // URLs aus der Portal-Basis (wie der Canonical) statt route(), damit
+        // Host und Canonical auch bei forceRootUrl-Abweichungen übereinstimmen.
+        $breadcrumbs = collect([
+            ['name' => $brandLabel, 'item' => $portalBase.'/'.app()->getLocale()],
+            $categoryName && $categorySlug ? ['name' => $categoryName, 'item' => $portalBase.'/'.app()->getLocale().'/category/'.$categorySlug] : null,
+            ['name' => $release->title, 'item' => $portalBase.'/'.app()->getLocale().'/press-release/'.$release->slug],
+        ])->filter()->values();
+
+        $jsonLd = [
+            '@context' => 'https://schema.org',
+            '@graph' => [
+                array_filter([
+                    '@type' => 'NewsArticle',
+                    'mainEntityOfPage' => ['@type' => 'WebPage', '@id' => $shareUrl],
+                    'headline' => Str::limit($release->title, 110),
+                    'description' => filled($lead) ? $lead : $teaser,
+                    'image' => $imageUrl ? [$imageUrl] : null,
+                    'datePublished' => $publishedAt?->toIso8601String(),
+                    'dateModified' => $modifiedAt?->toIso8601String(),
+                    'articleSection' => $categoryName,
+                    'keywords' => $keywords->isNotEmpty() ? $keywords->implode(', ') : null,
+                    'wordCount' => $wordCount ?: null,
+                    'inLanguage' => app()->getLocale(),
+                    'isAccessibleForFree' => true,
+                    'author' => $companyName ? array_filter([
+                        '@type' => 'Organization',
+                        'name' => $companyName,
+                        'url' => $company?->slug ? $portalBase.'/'.app()->getLocale().'/newsroom/'.$company->slug : null,
+                    ]) : null,
+                    'publisher' => ['@type' => 'Organization', 'name' => $brandLabel, 'url' => $portalBase],
+                ], fn ($value) => $value !== null),
+                [
+                    '@type' => 'BreadcrumbList',
+                    'itemListElement' => $breadcrumbs->map(fn (array $crumb, int $index) => [
+                        '@type' => 'ListItem',
+                        'position' => $index + 1,
+                        'name' => $crumb['name'],
+                        'item' => $crumb['item'],
+                    ])->all(),
+                ],
+            ],
+        ];
+    }
 @endphp
 
 @section('title', $release->title.' – '.$brandLabel)
@@ -95,6 +152,28 @@
     @section('robots', 'noindex,nofollow')
 @else
     @section('canonical', $shareUrl)
+
+    @section('meta_extra')
+        @if ($publishedAt)
+            <meta property="article:published_time" content="{{ $publishedAt->toIso8601String() }}">
+        @endif
+        @if ($release->updated_at?->greaterThan($publishedAt ?? $release->updated_at))
+            <meta property="article:modified_time" content="{{ $release->updated_at->toIso8601String() }}">
+        @endif
+        @if ($categoryName)
+            <meta property="article:section" content="{{ $categoryName }}">
+        @endif
+        @foreach ($keywords as $keyword)
+            <meta property="article:tag" content="{{ $keyword }}">
+        @endforeach
+        @if ($imageUrl && ($imageCaption || $release->title))
+            <meta property="og:image:alt" content="{{ $imageCaption ?: $release->title }}">
+        @endif
+    @endsection
+
+    @section('structured_data')
+        <x-web.structured-data :data="$jsonLd" />
+    @endsection
 @endif
 
 @section('content')
diff --git a/tests/Feature/Web/StructuredDataTest.php b/tests/Feature/Web/StructuredDataTest.php
new file mode 100644
index 00000000..4c24daf3
--- /dev/null
+++ b/tests/Feature/Web/StructuredDataTest.php
@@ -0,0 +1,119 @@
+<?php
+
+use App\Enums\Portal;
+use App\Enums\PressReleaseStatus;
+use App\Models\Category;
+use App\Models\Company;
+use App\Models\PressRelease;
+use App\Models\User;
+use App\Services\Auth\MagicLinkGenerator;
+use Tests\TestCase;
+
+function makeStructuredDataRelease(): PressRelease
+{
+    $category = Category::factory()->create(['portal' => Portal::Businessportal24]);
+    $category->translations()->create(['locale' => 'de', 'name' => 'Technologie', 'slug' => 'technologie']);
+
+    $company = Company::factory()->businessportal24()->create(['name' => 'Muster GmbH']);
+
+    return PressRelease::factory()
+        ->published()
+        ->forPortal(Portal::Businessportal24)
+        ->for($category)
+        ->for($company)
+        ->create([
+            'slug' => 'strukturierte-daten-pm',
+            'title' => 'Strukturierte Daten für Pressemitteilungen',
+            'published_at' => now()->subDay(),
+        ]);
+}
+
+test('the release detail page emits NewsArticle and BreadcrumbList JSON-LD', function () {
+    /** @var TestCase $this */
+    makeStructuredDataRelease();
+
+    $this->get('https://businessportal24.test/de/press-release/strukturierte-daten-pm')
+        ->assertSuccessful()
+        ->assertSee('<script type="application/ld+json">', false)
+        ->assertSee('"@type":"NewsArticle"', false)
+        ->assertSee('"headline":"Strukturierte Daten für Pressemitteilungen"', false)
+        ->assertSee('"datePublished"', false)
+        ->assertSee('"publisher":{"@type":"Organization","name":"businessportal24"', false)
+        ->assertSee('"author":{"@type":"Organization","name":"Muster GmbH"', false)
+        ->assertSee('"@type":"BreadcrumbList"', false)
+        ->assertSee('"articleSection":"Technologie"', false);
+});
+
+test('the release detail page emits article meta tags and og locale', function () {
+    /** @var TestCase $this */
+    makeStructuredDataRelease();
+
+    $this->get('https://businessportal24.test/de/press-release/strukturierte-daten-pm')
+        ->assertSuccessful()
+        ->assertSee('<meta property="article:published_time" content="', false)
+        ->assertSee('<meta property="article:section" content="Technologie">', false)
+        ->assertSee('<meta property="og:locale" content="de_DE">', false);
+});
+
+test('the private preview emits neither JSON-LD nor article meta tags', function () {
+    /** @var TestCase $this */
+    $owner = User::factory()->create();
+    $release = PressRelease::factory()->forPortal(Portal::Businessportal24)->create([
+        'user_id' => $owner->id,
+        'status' => PressReleaseStatus::Draft->value,
+    ]);
+
+    $share = app(MagicLinkGenerator::class)->createPressReleaseShareLink($release, $owner);
+
+    $this->get(route('press-releases.preview', ['token' => $share['plain_token']]))
+        ->assertOk()
+        ->assertDontSee('application/ld+json', false)
+        ->assertDontSee('article:published_time', false);
+});
+
+test('a portal homepage emits WebSite JSON-LD with a SearchAction', function () {
+    /** @var TestCase $this */
+    $this->get('https://presseecho.test/de')
+        ->assertSuccessful()
+        ->assertSee('"@type":"WebSite"', false)
+        ->assertSee('"@type":"SearchAction"', false)
+        ->assertSee('https://presseecho.test/de/suche?q={search_term_string}', false);
+});
+
+test('the newsroom page emits Organization JSON-LD for the company', function () {
+    /** @var TestCase $this */
+    $category = Category::factory()->create(['portal' => Portal::Businessportal24]);
+    $category->translations()->create(['locale' => 'de', 'name' => 'Wirtschaft', 'slug' => 'wirtschaft']);
+
+    $company = Company::factory()->businessportal24()->create([
+        'name' => 'Newsroom AG',
+        'website' => 'https://newsroom-ag.example',
+    ]);
+
+    PressRelease::factory()
+        ->published()
+        ->forPortal(Portal::Businessportal24)
+        ->for($category)
+        ->for($company)
+        ->create(['published_at' => now()->subDay()]);
+
+    $this->get('https://businessportal24.test/de/newsroom/'.$company->slug)
+        ->assertSuccessful()
+        ->assertSee('"@type":"Organization"', false)
+        ->assertSee('"name":"Newsroom AG"', false)
+        ->assertSee('"sameAs":["https://newsroom-ag.example"]', false);
+});
+
+test('the category page emits BreadcrumbList JSON-LD and localized hreflang links', function () {
+    /** @var TestCase $this */
+    $category = Category::factory()->create(['portal' => Portal::Businessportal24]);
+    $category->translations()->create(['locale' => 'de', 'name' => 'Technologie', 'slug' => 'technologie']);
+    $category->translations()->create(['locale' => 'en', 'name' => 'Technology', 'slug' => 'technology']);
+
+    $this->get('https://businessportal24.test/de/category/technologie')
+        ->assertSuccessful()
+        ->assertSee('"@type":"BreadcrumbList"', false)
+        ->assertSee('"name":"Technologie"', false)
+        ->assertSee('<link rel="alternate" hreflang="de" href="https://businessportal24.test/de/category/technologie">', false)
+        ->assertSee('<link rel="alternate" hreflang="en" href="https://businessportal24.test/en/category/technology">', false);
+});