diff --git a/src/Entity/ProjectSystem/Project.php b/src/Entity/ProjectSystem/Project.php
index 352d42c4..f202beaa 100644
--- a/src/Entity/ProjectSystem/Project.php
+++ b/src/Entity/ProjectSystem/Project.php
@@ -23,6 +23,7 @@ declare(strict_types=1);
 namespace App\Entity\ProjectSystem;
 
 use App\Repository\Parts\DeviceRepository;
+use App\Validator\Constraints\UniqueObjectCollection;
 use Doctrine\DBAL\Types\Types;
 use App\Entity\Attachments\ProjectAttachment;
 use App\Entity\Base\AbstractStructuralDBElement;
@@ -56,6 +57,8 @@ class Project extends AbstractStructuralDBElement
     #[Assert\Valid]
     #[Groups(['extended', 'full'])]
     #[ORM\OneToMany(targetEntity: ProjectBOMEntry::class, mappedBy: 'project', cascade: ['persist', 'remove'], orphanRemoval: true)]
+    #[UniqueObjectCollection(fields: ['part'], message: 'project.bom_entry.part_already_in_bom')]
+    #[UniqueObjectCollection(fields: ['name'], message: 'project.bom_entry.name_already_in_bom')]
     protected Collection $bom_entries;
 
     #[ORM\Column(type: Types::INTEGER)]
diff --git a/src/Entity/ProjectSystem/ProjectBOMEntry.php b/src/Entity/ProjectSystem/ProjectBOMEntry.php
index af974b5f..8955b1cf 100644
--- a/src/Entity/ProjectSystem/ProjectBOMEntry.php
+++ b/src/Entity/ProjectSystem/ProjectBOMEntry.php
@@ -22,6 +22,7 @@ declare(strict_types=1);
 
 namespace App\Entity\ProjectSystem;
 
+use App\Validator\UniqueValidatableInterface;
 use Doctrine\DBAL\Types\Types;
 use App\Entity\Base\AbstractDBElement;
 use App\Entity\Base\TimestampTrait;
@@ -38,12 +39,10 @@ use Symfony\Component\Validator\Context\ExecutionContextInterface;
 /**
  * The ProjectBOMEntry class represents an entry in a project's BOM.
  */
-#[UniqueEntity(fields: ['part', 'project'], message: 'project.bom_entry.part_already_in_bom')]
-#[UniqueEntity(fields: ['name', 'project'], message: 'project.bom_entry.name_already_in_bom', ignoreNull: true)]
 #[ORM\HasLifecycleCallbacks]
 #[ORM\Entity]
 #[ORM\Table('project_bom_entries')]
-class ProjectBOMEntry extends AbstractDBElement
+class ProjectBOMEntry extends AbstractDBElement implements UniqueValidatableInterface
 {
     use TimestampTrait;
 
@@ -270,4 +269,11 @@ class ProjectBOMEntry extends AbstractDBElement
     }
 
 
+    public function getComparableFields(): array
+    {
+        return [
+            'name' => $this->getName(),
+            'part' => $this->getPart()?->getID(),
+        ];
+    }
 }
diff --git a/src/Validator/Constraints/UniqueObjectCollection.php b/src/Validator/Constraints/UniqueObjectCollection.php
new file mode 100644
index 00000000..574959a8
--- /dev/null
+++ b/src/Validator/Constraints/UniqueObjectCollection.php
@@ -0,0 +1,62 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2023 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace App\Validator\Constraints;
+
+use InvalidArgumentException;
+use Symfony\Component\Validator\Constraint;
+
+#[\Attribute(\Attribute::TARGET_PROPERTY | \Attribute::TARGET_METHOD | \Attribute::IS_REPEATABLE)]
+class UniqueObjectCollection extends Constraint
+{
+    public const IS_NOT_UNIQUE = '7911c98d-b845-4da0-94b7-a8dac36bc55a';
+
+    public array|string $fields = [];
+
+    protected const ERROR_NAMES = [
+        self::IS_NOT_UNIQUE => 'IS_NOT_UNIQUE',
+    ];
+
+    public string $message = 'This collection should contain only unique elements.';
+    public $normalizer;
+
+    /**
+     * @param array|string $fields the combination of fields that must contain unique values or a set of options
+     */
+    public function __construct(
+        array $options = null,
+        string $message = null,
+        callable $normalizer = null,
+        array $groups = null,
+        mixed $payload = null,
+        array|string $fields = null,
+        public bool $allowNull = true,
+    ) {
+        parent::__construct($options, $groups, $payload);
+
+        $this->message = $message ?? $this->message;
+        $this->normalizer = $normalizer ?? $this->normalizer;
+        $this->fields = $fields ?? $this->fields;
+
+        if (null !== $this->normalizer && !\is_callable($this->normalizer)) {
+            throw new InvalidArgumentException(sprintf('The "normalizer" option must be a valid callable ("%s" given).', get_debug_type($this->normalizer)));
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Validator/Constraints/UniqueObjectCollectionValidator.php b/src/Validator/Constraints/UniqueObjectCollectionValidator.php
new file mode 100644
index 00000000..60486c2b
--- /dev/null
+++ b/src/Validator/Constraints/UniqueObjectCollectionValidator.php
@@ -0,0 +1,113 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2023 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace App\Validator\Constraints;
+
+use App\Entity\Base\AbstractDBElement;
+use App\Validator\UniqueValidatableInterface;
+use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
+use Symfony\Component\Serializer\Serializer;
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+use Symfony\Component\Validator\Exception\UnexpectedTypeException;
+use Symfony\Component\Validator\Exception\UnexpectedValueException;
+
+class UniqueObjectCollectionValidator extends ConstraintValidator
+{
+
+    public function validate(mixed $value, Constraint $constraint)
+    {
+        if (!$constraint instanceof UniqueObjectCollection) {
+            throw new UnexpectedTypeException($constraint, UniqueObjectCollection::class);
+        }
+
+        $fields = (array) $constraint->fields;
+
+        if (null === $value) {
+            return;
+        }
+
+        if (!\is_array($value) && !$value instanceof \IteratorAggregate) {
+            throw new UnexpectedValueException($value, 'array|IteratorAggregate');
+        }
+
+        $collectionElements = [];
+        $normalizer = $this->getNormalizer($constraint);
+        foreach ($value as $key => $object) {
+
+            if (!$object instanceof UniqueValidatableInterface) {
+                throw new UnexpectedValueException($object, UniqueValidatableInterface::class);
+            }
+
+            //Convert the object to an array using the helper function
+            $element = $object->getComparableFields();
+
+            if ($fields && !$element = $this->reduceElementKeys($fields, $element, $constraint)) {
+                continue;
+            }
+
+            $element = $normalizer($element);
+
+            if (\in_array($element, $collectionElements, true)) {
+
+                $violation = $this->context->buildViolation($constraint->message);
+
+                $violation->atPath('[' . $key . ']' . '.' . $constraint->fields[0]);
+
+                $violation->setParameter('{{ value }}', $this->formatValue($value))
+                    ->setCode(UniqueObjectCollection::IS_NOT_UNIQUE)
+                    ->addViolation();
+
+                return;
+            }
+            $collectionElements[] = $element;
+        }
+    }
+
+    private function getNormalizer(UniqueObjectCollection $unique): callable
+    {
+        if (null === $unique->normalizer) {
+            return static fn ($value) => $value;
+        }
+
+        return $unique->normalizer;
+    }
+
+    private function reduceElementKeys(array $fields, array $element, UniqueObjectCollection $constraint): array
+    {
+        $output = [];
+        foreach ($fields as $field) {
+            if (!\is_string($field)) {
+                throw new UnexpectedTypeException($field, 'string');
+            }
+            if (\array_key_exists($field, $element)) {
+                //Ignore null values if specified
+                if ($element[$field] === null && $constraint->allowNull) {
+                    continue;
+                }
+
+                $output[$field] = $element[$field];
+            }
+        }
+
+        return $output;
+    }
+
+}
\ No newline at end of file
diff --git a/src/Validator/UniqueValidatableInterface.php b/src/Validator/UniqueValidatableInterface.php
new file mode 100644
index 00000000..97e3a0b9
--- /dev/null
+++ b/src/Validator/UniqueValidatableInterface.php
@@ -0,0 +1,32 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2023 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace App\Validator;
+
+interface UniqueValidatableInterface
+{
+    /**
+     * This method should return an array of fields that should be used to compare the objects for the UniqueObjectCollection constraint.
+     * All instances of the same class should return the same fields.
+     * The value must be a comparable value (e.g. string, int, float, bool, null).
+     * @return array An array of the form ['field1' => 'value1', 'field2' => 'value2', ...]
+     */
+    public function getComparableFields(): array;
+}
\ No newline at end of file
diff --git a/templates/form/collection_types_layout.html.twig b/templates/form/collection_types_layout.html.twig
index 53311061..9cc1297b 100644
--- a/templates/form/collection_types_layout.html.twig
+++ b/templates/form/collection_types_layout.html.twig
@@ -38,16 +38,16 @@
             </button>
         </td>
         <td>
-            {{ form_errors(form.quantity) }}
             {{ form_widget(form.quantity) }}
+            {{ form_errors(form.quantity) }}
         </td>
         <td style="min-width: 250px;">
-            {{ form_errors(form.part) }}
             {{ form_widget(form.part) }}
+            {{ form_errors(form.part) }}
         </td>
         <td>
-            {{ form_errors(form.name) }}
             {{ form_widget(form.name) }}
+            {{ form_errors(form.name) }}
         </td>
         <td>
             <button type="button" class="btn btn-danger lot_btn_delete" {{ collection.delete_btn() }}>
diff --git a/templates/projects/info/_bom.html.twig b/templates/projects/info/_bom.html.twig
index d8412726..bed96dde 100644
--- a/templates/projects/info/_bom.html.twig
+++ b/templates/projects/info/_bom.html.twig
@@ -1,6 +1,6 @@
 {% import "components/datatables.macro.html.twig" as datatables %}
 
-<div class="btn-group mb-2">
+<div class="btn-group mb-2 mt-2">
     <a class="btn btn-success" {% if not is_granted('@projects.edit') %}disabled{% endif %}
        href="{{ path('project_add_parts', {"id": project.id, "_redirect": app.request.requestUri}) }}">
         <i class="fa-solid fa-square-plus fa-fw"></i>