diff --git a/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/FilterSettingTypeRendererCore.php b/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/FilterSettingTypeRendererCore.php
index 79eff979c..2d34399cf 100644
--- a/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/FilterSettingTypeRendererCore.php
+++ b/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/FilterSettingTypeRendererCore.php
@@ -3,7 +3,7 @@
 /**
  * This file is part of MetaModels/core.
  *
- * (c) 2012-2024 The MetaModels team.
+ * (c) 2012-2026 The MetaModels team.
  *
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
@@ -14,7 +14,7 @@
  * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
  * @author     Sven Baumann <baumann.sv@gmail.com>
  * @author     Ingolf Steinhardt <info@e-spin.de>
- * @copyright  2012-2024 The MetaModels team.
+ * @copyright  2012-2026 The MetaModels team.
  * @license    https://github.com/MetaModels/core/blob/master/LICENSE LGPL-3.0-or-later
  * @filesource
  */
@@ -37,14 +37,13 @@ class FilterSettingTypeRendererCore extends AbstractFilterSettingTypeRenderer
     #[\Override]
     protected function getTypes()
     {
-        return ['idlist', 'simplelookup', 'customsql', 'conditionand', 'conditionor'];
+        return ['idlist', 'simplelookup', 'customsql', 'conditionand', 'conditionor', 'conditiongate'];
     }
 
     /**
      * Retrieve the parameters for the label.
      *
      * @param EnvironmentInterface $environment The translator in use.
-     *
      * @param ModelInterface       $model       The model.
      *
      * @return array
@@ -52,9 +51,10 @@ protected function getTypes()
     #[\Override]
     protected function getLabelParameters(EnvironmentInterface $environment, ModelInterface $model)
     {
-        if ($model->getProperty('type') == 'simplelookup') {
+        if ($model->getProperty('type') === 'simplelookup') {
             return $this->getLabelParametersWithAttributeAndUrlParam($environment, $model);
         }
+
         return $this->getLabelParametersNormal($environment, $model);
     }
 }
diff --git a/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/PasteButtonListener.php b/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/PasteButtonListener.php
index 4aa148d2e..14b3665d3 100644
--- a/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/PasteButtonListener.php
+++ b/src/CoreBundle/EventListener/DcGeneral/Table/FilterSetting/PasteButtonListener.php
@@ -25,9 +25,11 @@
 use ContaoCommunityAlliance\DcGeneral\Clipboard\Filter;
 use ContaoCommunityAlliance\DcGeneral\Clipboard\ItemInterface;
 use ContaoCommunityAlliance\DcGeneral\Contao\View\Contao2BackendView\Event\GetPasteButtonEvent;
+use ContaoCommunityAlliance\DcGeneral\Controller\ModelCollector;
 use ContaoCommunityAlliance\DcGeneral\Data\ModelId;
 use ContaoCommunityAlliance\DcGeneral\Data\ModelInterface;
 use MetaModels\Filter\Setting\IFilterSettingFactory;
+use MetaModels\Filter\Setting\IFilterSettingTypeFactory;
 
 /**
  * This class takes care of enabling and disabling of the paste button.
@@ -41,6 +43,8 @@ class PasteButtonListener
      */
     private IFilterSettingFactory $filterFactory;
 
+    private \SplObjectStorage $parents;
+
     /**
      * Create a new instance.
      *
@@ -49,6 +53,7 @@ class PasteButtonListener
     public function __construct(IFilterSettingFactory $filterFactory)
     {
         $this->filterFactory = $filterFactory;
+        $this->parents = new \SplObjectStorage();
     }
 
     /**
@@ -79,11 +84,45 @@ public function handle(GetPasteButtonEvent $event)
 
             return;
         }
-        $factory = $this->filterFactory->getTypeFactory($model->getProperty('type'));
+        $factory = $this->getFactoryFor($model);
+        if (null === $factory) {
+            // Unknown type, disallow paste.
+            $event->setPasteIntoDisabled(true);
+            $event->setPasteAfterDisabled(true);
+            return;
+        }
 
         // If setting does not support children, omit them.
-        if ($model->getId() && !($factory && $factory->isNestedType())) {
+        if ($model->getId() && !($factory->isNestedType())) {
             $event->setPasteIntoDisabled(true);
         }
+
+        $collector = new ModelCollector($event->getEnvironment());
+        if ($factory->isNestedType() && (null !== ($maxChildren = $factory->getMaxChildren()))) {
+            if ($maxChildren < count($collector->collectDirectChildrenOf($model))) {
+                $event->setPasteIntoDisabled(true);
+            }
+        }
+        if (!$this->parents->contains($model)) {
+            $this->parents[$model] = $collector->searchParentOf($model);
+        }
+        $parent = $this->parents[$model];
+        if (!$parent) {
+            return;
+        }
+        $parentFactory = $this->getFactoryFor($parent);
+        if (!$parentFactory?->isNestedType() || (null === ($maxChildren = $parentFactory?->getMaxChildren()))) {
+            return;
+        }
+        $siblings = $collector->collectSiblingsOf($model, $parent?->getId());
+        // FIXME: Except, if we are already contained and just get moved within parent :(
+        if ($maxChildren <= $siblings->length()) {
+            $event->setPasteAfterDisabled(true);
+        }
+    }
+
+    private function getFactoryFor(ModelInterface $model): ?IFilterSettingTypeFactory
+    {
+        return $this->filterFactory->getTypeFactory($model->getProperty('type'));
     }
 }
diff --git a/src/CoreBundle/Resources/config/filter-settings.yml b/src/CoreBundle/Resources/config/filter-settings.yml
index 7c2e27824..d244ab9f4 100644
--- a/src/CoreBundle/Resources/config/filter-settings.yml
+++ b/src/CoreBundle/Resources/config/filter-settings.yml
@@ -54,3 +54,11 @@ services:
           - '@translator'
         tags:
           - { name: metamodels.filter_factory }
+
+    MetaModels\Filter\Setting\ConditionGateFilterSettingTypeFactory:
+        arguments:
+          - '@metamodels.expression-language'
+          - '@request_stack'
+          - '@translator'
+        tags:
+          - { name: metamodels.filter_factory }
diff --git a/src/CoreBundle/Resources/config/services.yml b/src/CoreBundle/Resources/config/services.yml
index 4152cf2c8..fbc728799 100644
--- a/src/CoreBundle/Resources/config/services.yml
+++ b/src/CoreBundle/Resources/config/services.yml
@@ -356,3 +356,6 @@ services:
       decorates: 'cca.backend-help-provider'
       arguments:
         $previous: '@.inner'
+
+    metamodels.expression-language:
+      class: Symfony\Component\ExpressionLanguage\ExpressionLanguage
diff --git a/src/CoreBundle/Resources/contao/dca/tl_metamodel_filtersetting.php b/src/CoreBundle/Resources/contao/dca/tl_metamodel_filtersetting.php
index 242c66f6c..8899228d7 100644
--- a/src/CoreBundle/Resources/contao/dca/tl_metamodel_filtersetting.php
+++ b/src/CoreBundle/Resources/contao/dca/tl_metamodel_filtersetting.php
@@ -94,7 +94,14 @@
                         'remote'    => 'id',
                         'operation' => '=',
                     ],
-                ]
+                ],
+                'inverse' => [
+                    [
+                        'local'     => 'pid',
+                        'remote'    => 'id',
+                        'operation' => '=',
+                    ],
+                ],
             ]
         ],
         'rootEntries'    => [
@@ -223,6 +230,14 @@
                 'stop_after_match'
             ]
         ],
+        'conditiongate extends default'      => [
+            'config' => [
+                'gate_expression'
+            ],
+            '+fefilter' => [
+                'onlypossible',
+            ],
+        ],
         'idlist extends default'           => [
             '+config' => [
                 'items'
@@ -450,6 +465,19 @@
             ],
             'sql'         => "char(1) NOT NULL default ''"
         ],
+        'gate_expression'     => [
+            'label'       => 'gate_expression.label',
+            'description' => 'gate_expression.description',
+            'exclude'     => true,
+            'inputType'   => 'text',
+            'eval'        => [
+                'alwaysSave'     => true,
+                'decodeEntities' => true,
+                'mandatory'      => true,
+                'tl_class'       => 'clr',
+            ],
+            'sql'         => "text NOT NULL default ''"
+        ],
         'label'                => [
             'label'       => 'label.label',
             'description' => 'label.description',
diff --git a/src/CoreBundle/Resources/translations/tl_metamodel_filtersetting.en.xlf b/src/CoreBundle/Resources/translations/tl_metamodel_filtersetting.en.xlf
index 607b30cbf..f24a8dc06 100644
--- a/src/CoreBundle/Resources/translations/tl_metamodel_filtersetting.en.xlf
+++ b/src/CoreBundle/Resources/translations/tl_metamodel_filtersetting.en.xlf
@@ -298,6 +298,12 @@
       <trans-unit id="typenames.conditionand" resname="typenames.conditionand">
         <source>AND condition</source>
       </trans-unit>
+      <trans-unit id="typenames.conditiongate" resname="typenames.conditiongate">
+        <source>Gate condition</source>
+      </trans-unit>
+      <trans-unit id="error.condition_max_children" resname="error.condition_max_children">
+        <source>The condition "%name%" can only have "%max%" children max.</source>
+      </trans-unit>
       <trans-unit id="typedesc._attribute_" resname="typedesc._attribute_">
         <source>&lt;em&gt;[%colName%, "%name%"]&lt;/em&gt;</source>
       </trans-unit>
@@ -322,6 +328,9 @@
       <trans-unit id="typedesc.conditionand" resname="typedesc.conditionand">
         <source>%1$s &lt;strong&gt;%2$s&lt;/strong&gt; %4$s</source>
       </trans-unit>
+      <trans-unit id="typedesc.conditiongate" resname="typedesc.conditiongate">
+        <source>%1$s &lt;strong&gt;%2$s&lt;/strong&gt; %4$s</source>
+      </trans-unit>
       <trans-unit id="items.label" resname="items.label">
         <source>Items</source>
       </trans-unit>
diff --git a/src/Filter/Rules/Condition/ConditionGate.php b/src/Filter/Rules/Condition/ConditionGate.php
new file mode 100644
index 000000000..97542287b
--- /dev/null
+++ b/src/Filter/Rules/Condition/ConditionGate.php
@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MetaModels\Filter\Rules\Condition;
+
+use MetaModels\Filter\IFilter;
+use MetaModels\Filter\IFilterRule;
+use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
+
+/**
+ * This is the MetaModel filter interface.
+ */
+final readonly class ConditionGate implements IFilterRule
+{
+    public function __construct(
+        private string $expression,
+        private array $parameters,
+        private ExpressionLanguage $expressionLanguage,
+        private ?IFilter $ifTrue,
+        private ?IFilter $ifFalse,
+    ) {
+    }
+
+    /** @return list<string>|null */
+    #[\Override]
+    public function getMatchingIds(): ?array
+    {
+        if ((bool) $this->expressionLanguage->evaluate($this->expression, $this->parameters)) {
+            return $this->ifTrue?->getMatchingIds();
+        }
+        if (null !== $this->ifFalse) {
+            return $this->ifFalse->getMatchingIds();
+        }
+        return [];
+    }
+}
diff --git a/src/Filter/Setting/Condition/ConditionGate.php b/src/Filter/Setting/Condition/ConditionGate.php
new file mode 100644
index 000000000..99ac1bc6e
--- /dev/null
+++ b/src/Filter/Setting/Condition/ConditionGate.php
@@ -0,0 +1,222 @@
+<?php
+
+/**
+ * This file is part of MetaModels/core.
+ *
+ * (c) 2012-2019 The MetaModels team.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * This project is provided in good faith and hope to be usable by anyone.
+ *
+ * @package    MetaModels/core
+ * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
+ * @author     David Maack <david.maack@arcor.de>
+ * @author     Sven Baumann <baumann.sv@gmail.com>
+ * @copyright  2012-2019 The MetaModels team.
+ * @license    https://github.com/MetaModels/core/blob/master/LICENSE LGPL-3.0-or-later
+ * @filesource
+ */
+
+namespace MetaModels\Filter\Setting\Condition;
+
+use Contao\Message;
+use MetaModels\Filter\IFilter;
+use MetaModels\Filter\Rules\Condition\ConditionGate as FilterRuleGate;
+use MetaModels\Filter\Setting\ISimple;
+use MetaModels\Filter\Setting\IWithChildren;
+use MetaModels\FrontendIntegration\FrontendFilterOptions;
+use MetaModels\IItem;
+use MetaModels\IMetaModel;
+use MetaModels\Render\Setting\ICollection as IRenderSettings;
+use Override;
+use RuntimeException;
+use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
+use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Contracts\Translation\TranslatorInterface;
+
+use function array_merge;
+use function count;
+
+/**
+ * This filter condition generates a filter rule, that represents a simple "if this then that else that".
+ */
+final class ConditionGate implements IWithChildren
+{
+    /** @var list<ISimple> */
+    private array $children = [];
+
+    public function __construct(
+        private readonly array $data,
+        private readonly ExpressionLanguage $expressionLanguage,
+        private readonly RequestStack $requestStack,
+        private readonly IMetaModel $metaModel,
+        private readonly TranslatorInterface $translator,
+    ) {
+    }
+
+    #[Override]
+    public function prepareRules(IFilter $objFilter, $arrFilterUrl): void
+    {
+        $ifTrue = null;
+        if ($this->children[0] ?? null) {
+            $ifTrue = $this->metaModel->getEmptyFilter();
+            $this->children[0]->prepareRules($ifTrue, $arrFilterUrl);
+        }
+        $ifFalse = null;
+        if ($this->children[1] ?? null) {
+            $ifFalse = $this->metaModel->getEmptyFilter();
+            $this->children[1]->prepareRules($ifFalse, $arrFilterUrl);
+        }
+
+        $filterRule = new FilterRuleGate(
+            $this->getExpression(),
+            $this->getExpressionParameters($arrFilterUrl),
+            $this->expressionLanguage,
+            $ifTrue,
+            $ifFalse,
+        );
+
+        $objFilter->addFilterRule($filterRule);
+    }
+
+    #[Override]
+    public function addChild(ISimple $objFilterSetting): void
+    {
+        if (count($this->children) >= 2) {
+            // FIXME: call getTypeName() for name.
+            Message::addInfo(
+                $this->translator->trans(
+                    'error.condition_max_children',
+                    ['%name%' => 'conditiongate', '%max%' => '2'],
+                    'tl_metamodel_filtersetting'
+                )
+            );
+            return;
+            //throw new RuntimeException('A condition gate can only have two children max.');
+        }
+        $this->children[] = $objFilterSetting;
+    }
+
+    #[Override]
+    public function get($strKey): mixed
+    {
+        return $this->data[$strKey] ?? null;
+    }
+
+    #[Override]
+    public function generateFilterUrlFrom(IItem $objItem, IRenderSettings $objRenderSetting): array
+    {
+        $result = [];
+        foreach ($this->children as $child) {
+            $result[] = $child->generateFilterUrlFrom($objItem, $objRenderSetting);
+        }
+
+        return array_merge(...$result);
+    }
+
+    #[Override]
+    public function getParameters(): array
+    {
+        $parameters = [];
+        foreach ($this->children as $child) {
+            $parameters[] = $child->getParameters();
+        }
+
+        return array_merge(...$parameters);
+    }
+
+    #[Override]
+    public function getParameterDCA(): array
+    {
+        $parameters = [];
+        foreach ($this->children as $child) {
+            $parameters[] = $child->getParameterDCA();
+        }
+
+        return array_merge(...$parameters);
+    }
+
+    #[Override]
+    public function getParameterFilterNames(): array
+    {
+        $parameters = [];
+        foreach ($this->children as $objSetting) {
+            $parameters[] = $objSetting->getParameterFilterNames();
+        }
+
+        return array_merge(...$parameters);
+    }
+
+    /** @SuppressWarnings(PHPMD.LongVariable) */
+    #[Override]
+    public function getParameterFilterWidgets(
+        $arrIds,
+        $arrFilterUrl,
+        $arrJumpTo,
+        FrontendFilterOptions $objFrontendFilterOptions
+    ): array {
+        if (null !== ($child = $this->children[0])) {
+            return $child->getParameterFilterWidgets(
+                $this->isConditionFulfilled($arrFilterUrl) && ((bool) $this->get('onlypossible')) ? $arrIds : null,
+                $arrFilterUrl,
+                $arrJumpTo,
+                $objFrontendFilterOptions
+            );
+        }
+        // TODO: besser weiter hirnen...
+        // $child = $this->getFilterForConditionState($arrFilterUrl);
+        // if ($child) {
+        //     return $child->getParameterFilterWidgets(
+        //         ((bool) $this->get('onlypossible')) ? $arrIds : null,
+        //         $arrFilterUrl,
+        //         $arrJumpTo,
+        //         $objFrontendFilterOptions
+        //     );
+        // }
+
+        return [];
+    }
+
+    #[Override]
+    public function getReferencedAttributes(): array
+    {
+        $attributes = [];
+        foreach ($this->children as $child) {
+            $attributes[] = $child->getReferencedAttributes();
+        }
+
+        return array_merge(...$attributes);
+    }
+
+    private function getFilterForConditionState(array $filterUrl): ?ISimple
+    {
+        if ($this->isConditionFulfilled($filterUrl)) {
+            return $this->children[0] ?? null;
+        }
+
+        return $this->children[1] ?? null;
+    }
+
+    private function isConditionFulfilled(array $filterUrl): bool
+    {
+        return (bool) $this->expressionLanguage->evaluate(
+            $this->getExpression(),
+            $this->getExpressionParameters($filterUrl)
+        );
+    }
+
+    private function getExpression(): string
+    {
+        return (string) $this->data['gate_expression'];
+    }
+
+    private function getExpressionParameters(array $arrFilterUrl): array
+    {
+        return [
+            'filterUrl' => $arrFilterUrl,
+            'request'   => $this->requestStack->getCurrentRequest(),
+        ];
+    }
+}
diff --git a/src/Filter/Setting/ConditionAndFilterSettingTypeFactory.php b/src/Filter/Setting/ConditionAndFilterSettingTypeFactory.php
index cb0c1379a..e4a788036 100644
--- a/src/Filter/Setting/ConditionAndFilterSettingTypeFactory.php
+++ b/src/Filter/Setting/ConditionAndFilterSettingTypeFactory.php
@@ -3,7 +3,7 @@
 /**
  * This file is part of MetaModels/core.
  *
- * (c) 2012-2024 The MetaModels team.
+ * (c) 2012-2026 The MetaModels team.
  *
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
@@ -14,7 +14,7 @@
  * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
  * @author     Sven Baumann <baumann.sv@gmail.com>
  * @author     Ingolf Steinhardt <info@e-spin.de>
- * @copyright  2012-2024 The MetaModels team.
+ * @copyright  2012-2026 The MetaModels team.
  * @license    https://github.com/MetaModels/core/blob/master/LICENSE LGPL-3.0-or-later
  * @filesource
  */
@@ -43,7 +43,7 @@ public function __construct(
 
         $this
             ->setTypeName('conditionand')
-            ->setTypeIcon('/bundles/metamodelscore/images/icons/filter_and.png')
+            ->setTypeIcon('bundles/metamodelscore/images/icons/filter_and.png')
             ->setTypeClass(ConditionAnd::class)
             ->allowAttributeTypes();
     }
diff --git a/src/Filter/Setting/ConditionGateFilterSettingTypeFactory.php b/src/Filter/Setting/ConditionGateFilterSettingTypeFactory.php
new file mode 100644
index 000000000..7c75a510d
--- /dev/null
+++ b/src/Filter/Setting/ConditionGateFilterSettingTypeFactory.php
@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MetaModels\Filter\Setting;
+
+use MetaModels\Filter\Setting\Condition\ConditionGate;
+use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
+use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Contracts\Translation\TranslatorInterface;
+
+/**
+ * Attribute type factory for GATE filter settings.
+ */
+class ConditionGateFilterSettingTypeFactory implements IFilterSettingTypeFactory
+{
+    public function __construct(
+        private readonly ExpressionLanguage $expressionLanguage,
+        private readonly RequestStack $requestStack,
+        private readonly TranslatorInterface $translator,
+    ) {
+    }
+
+    public function getTypeName(): string
+    {
+         return 'conditiongate';
+    }
+
+    public function getTypeIcon(): string
+    {
+        return 'bundles/metamodelscore/images/icons/filter_gate.png';
+    }
+
+    public function isNestedType(): bool
+    {
+        return true;
+    }
+
+    public function getMaxChildren(): int
+    {
+        return 2;
+    }
+
+    public function getKnownAttributeTypes(): ?array
+    {
+        return null;
+    }
+
+    public function addKnownAttributeType($typeName)
+    {
+        throw new \LogicException('Filter setting "' . ConditionGate::class . '" can not handle attributes.');
+    }
+
+    #[\Override]
+    public function createInstance($information, $filterSettings): ?ISimple
+    {
+        return new ConditionGate(
+            $information,
+            $this->expressionLanguage,
+            $this->requestStack,
+            $filterSettings->getMetaModel(),
+            $this->translator,
+        );
+    }
+}