diff --git a/src/Entity/Attachments/Attachment.php b/src/Entity/Attachments/Attachment.php
index fda0e3a8..ea06b1f3 100644
--- a/src/Entity/Attachments/Attachment.php
+++ b/src/Entity/Attachments/Attachment.php
@@ -57,12 +57,7 @@ use LogicException;
 #[ORM\Entity(repositoryClass: AttachmentRepository::class)]
 #[ORM\InheritanceType('SINGLE_TABLE')]
 #[ORM\DiscriminatorColumn(name: 'class_name', type: 'string')]
-#[ORM\DiscriminatorMap(['PartDB\Part' => PartAttachment::class, 'Part' => PartAttachment::class,
-    'PartDB\Device' => ProjectAttachment::class, 'Device' => ProjectAttachment::class, 'AttachmentType' => AttachmentTypeAttachment::class,
-    'Category' => CategoryAttachment::class, 'Footprint' => FootprintAttachment::class, 'Manufacturer' => ManufacturerAttachment::class,
-    'Currency' => CurrencyAttachment::class, 'Group' => GroupAttachment::class, 'MeasurementUnit' => MeasurementUnitAttachment::class,
-    'Storelocation' => StorageLocationAttachment::class, 'Supplier' => SupplierAttachment::class,
-    'User' => UserAttachment::class, 'LabelProfile' => LabelAttachment::class])]
+#[ORM\DiscriminatorMap(self::DISCRIMINATOR_MAP)]
 #[ORM\EntityListeners([AttachmentDeleteListener::class])]
 #[ORM\Table(name: '`attachments`')]
 #[ORM\Index(name: 'attachments_idx_id_element_id_class_name', columns: ['id', 'element_id', 'class_name'])]
@@ -89,9 +84,17 @@ use LogicException;
 #[ApiFilter(EntityFilter::class, properties: ["attachment_type"])]
 #[ApiFilter(DateFilter::class, strategy: DateFilter::EXCLUDE_NULL)]
 #[ApiFilter(OrderFilter::class, properties: ['name', 'id', 'addedDate', 'lastModified'])]
-#[DiscriminatorMap(typeProperty: '_type', mapping: ['part' => PartAttachment::class])]
+//This discriminator map is required for API platform to know which class to use for deserialization, when creating a new attachment.
+#[DiscriminatorMap(typeProperty: '_type', mapping: self::DISCRIMINATOR_MAP)]
 abstract class Attachment extends AbstractNamedDBElement
 {
+    private const DISCRIMINATOR_MAP = ['PartDB\Part' => PartAttachment::class, 'Part' => PartAttachment::class,
+        'PartDB\Device' => ProjectAttachment::class, 'Device' => ProjectAttachment::class, 'AttachmentType' => AttachmentTypeAttachment::class,
+        'Category' => CategoryAttachment::class, 'Footprint' => FootprintAttachment::class, 'Manufacturer' => ManufacturerAttachment::class,
+        'Currency' => CurrencyAttachment::class, 'Group' => GroupAttachment::class, 'MeasurementUnit' => MeasurementUnitAttachment::class,
+        'Storelocation' => StorageLocationAttachment::class, 'Supplier' => SupplierAttachment::class,
+        'User' => UserAttachment::class, 'LabelProfile' => LabelAttachment::class];
+
     /**
      * A list of file extensions, that browsers can show directly as image.
      * Based on: https://developer.mozilla.org/en-US/docs/Web/Media/Formats/Image_types
diff --git a/src/Entity/Attachments/AttachmentTypeAttachment.php b/src/Entity/Attachments/AttachmentTypeAttachment.php
index 31398595..0aeb3164 100644
--- a/src/Entity/Attachments/AttachmentTypeAttachment.php
+++ b/src/Entity/Attachments/AttachmentTypeAttachment.php
@@ -22,8 +22,10 @@ declare(strict_types=1);
 
 namespace App\Entity\Attachments;
 
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * A attachment attached to an attachmentType element.
@@ -39,5 +41,6 @@ class AttachmentTypeAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: AttachmentType::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/CategoryAttachment.php b/src/Entity/Attachments/CategoryAttachment.php
index 63b4178d..ecdd053a 100644
--- a/src/Entity/Attachments/CategoryAttachment.php
+++ b/src/Entity/Attachments/CategoryAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\Parts\Category;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a category element.
@@ -40,5 +42,6 @@ class CategoryAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Category::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/CurrencyAttachment.php b/src/Entity/Attachments/CurrencyAttachment.php
index 292da013..c58336bf 100644
--- a/src/Entity/Attachments/CurrencyAttachment.php
+++ b/src/Entity/Attachments/CurrencyAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\PriceInformations\Currency;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a currency element.
@@ -41,5 +43,6 @@ class CurrencyAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Currency::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/FootprintAttachment.php b/src/Entity/Attachments/FootprintAttachment.php
index 4d9b7caa..ce17c65e 100644
--- a/src/Entity/Attachments/FootprintAttachment.php
+++ b/src/Entity/Attachments/FootprintAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\Parts\Footprint;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a footprint element.
@@ -41,5 +43,6 @@ class FootprintAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Footprint::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/GroupAttachment.php b/src/Entity/Attachments/GroupAttachment.php
index 269e5b7d..ec80c98d 100644
--- a/src/Entity/Attachments/GroupAttachment.php
+++ b/src/Entity/Attachments/GroupAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\UserSystem\Group;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a Group element.
@@ -41,5 +43,6 @@ class GroupAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Group::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/LabelAttachment.php b/src/Entity/Attachments/LabelAttachment.php
index 5bf18969..63beab8a 100644
--- a/src/Entity/Attachments/LabelAttachment.php
+++ b/src/Entity/Attachments/LabelAttachment.php
@@ -42,8 +42,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\LabelSystem\LabelProfile;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * A attachment attached to a user element.
@@ -60,5 +62,6 @@ class LabelAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: LabelProfile::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/ManufacturerAttachment.php b/src/Entity/Attachments/ManufacturerAttachment.php
index cdbd7807..f7b27b00 100644
--- a/src/Entity/Attachments/ManufacturerAttachment.php
+++ b/src/Entity/Attachments/ManufacturerAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\Parts\Manufacturer;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a manufacturer element.
@@ -41,5 +43,6 @@ class ManufacturerAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Manufacturer::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/MeasurementUnitAttachment.php b/src/Entity/Attachments/MeasurementUnitAttachment.php
index 7b7c4f83..028f5436 100644
--- a/src/Entity/Attachments/MeasurementUnitAttachment.php
+++ b/src/Entity/Attachments/MeasurementUnitAttachment.php
@@ -24,8 +24,10 @@ namespace App\Entity\Attachments;
 
 use App\Entity\Parts\Manufacturer;
 use App\Entity\Parts\MeasurementUnit;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a measurement unit element.
@@ -40,5 +42,6 @@ class MeasurementUnitAttachment extends Attachment
 
     #[ORM\ManyToOne(targetEntity: MeasurementUnit::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/PartAttachment.php b/src/Entity/Attachments/PartAttachment.php
index dbda482c..36b0a3f8 100644
--- a/src/Entity/Attachments/PartAttachment.php
+++ b/src/Entity/Attachments/PartAttachment.php
@@ -46,7 +46,6 @@ class PartAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Part::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
-    // Set the correct type for the element property to use
-    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => Part::class])]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/ProjectAttachment.php b/src/Entity/Attachments/ProjectAttachment.php
index 84b0ac4c..ab9bd474 100644
--- a/src/Entity/Attachments/ProjectAttachment.php
+++ b/src/Entity/Attachments/ProjectAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\ProjectSystem\Project;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * A attachment attached to a device element.
@@ -40,5 +42,6 @@ class ProjectAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Project::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/StorageLocationAttachment.php b/src/Entity/Attachments/StorageLocationAttachment.php
index 301c202f..d27c2ff8 100644
--- a/src/Entity/Attachments/StorageLocationAttachment.php
+++ b/src/Entity/Attachments/StorageLocationAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\Parts\StorageLocation;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a measurement unit element.
@@ -41,5 +43,6 @@ class StorageLocationAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: StorageLocation::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/SupplierAttachment.php b/src/Entity/Attachments/SupplierAttachment.php
index 7afa8282..9cf9f4d1 100644
--- a/src/Entity/Attachments/SupplierAttachment.php
+++ b/src/Entity/Attachments/SupplierAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\Parts\Supplier;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * A attachment attached to a supplier element.
@@ -41,5 +43,6 @@ class SupplierAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: Supplier::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }
diff --git a/src/Entity/Attachments/UserAttachment.php b/src/Entity/Attachments/UserAttachment.php
index fef36eb5..322fd15f 100644
--- a/src/Entity/Attachments/UserAttachment.php
+++ b/src/Entity/Attachments/UserAttachment.php
@@ -23,8 +23,10 @@ declare(strict_types=1);
 namespace App\Entity\Attachments;
 
 use App\Entity\UserSystem\User;
+use App\Serializer\OverrideClassDenormalizer;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+use Symfony\Component\Serializer\Attribute\Context;
 
 /**
  * An attachment attached to a user element.
@@ -41,5 +43,6 @@ class UserAttachment extends Attachment
      */
     #[ORM\ManyToOne(targetEntity: User::class, inversedBy: 'attachments')]
     #[ORM\JoinColumn(name: 'element_id', nullable: false, onDelete: 'CASCADE')]
+    #[Context(denormalizationContext: [OverrideClassDenormalizer::CONTEXT_KEY => self::ALLOWED_ELEMENT_CLASS])]
     protected ?AttachmentContainingDBElement $element = null;
 }