diff --git a/api/src/Entity/Action.php b/api/src/Entity/Action.php
index 17c9e6cb4..c2431a087 100644
--- a/api/src/Entity/Action.php
+++ b/api/src/Entity/Action.php
@@ -15,6 +15,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Validator\Constraints as Assert;
 
@@ -48,6 +49,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Action
 {
diff --git a/api/src/Entity/Application.php b/api/src/Entity/Application.php
index 2afb2f2fd..bc355792b 100644
--- a/api/src/Entity/Application.php
+++ b/api/src/Entity/Application.php
@@ -16,6 +16,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Serializer\Annotation\MaxDepth;
 use Symfony\Component\Validator\Constraints as Assert;
@@ -50,6 +51,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Application
 {
diff --git a/api/src/Entity/CollectionEntity.php b/api/src/Entity/CollectionEntity.php
index 97823f723..8d97afdb0 100644
--- a/api/src/Entity/CollectionEntity.php
+++ b/api/src/Entity/CollectionEntity.php
@@ -51,6 +51,7 @@
  * })
  *
  * @UniqueEntity("name")
+ * @UniqueEntity("reference")
  */
 class CollectionEntity
 {
diff --git a/api/src/Entity/Cronjob.php b/api/src/Entity/Cronjob.php
index 862ba6b03..c05d7a116 100644
--- a/api/src/Entity/Cronjob.php
+++ b/api/src/Entity/Cronjob.php
@@ -13,6 +13,7 @@
 use Doctrine\ORM\Mapping as ORM;
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Validator\Constraints as Assert;
 
@@ -43,6 +44,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Cronjob
 {
diff --git a/api/src/Entity/Endpoint.php b/api/src/Entity/Endpoint.php
index 567c865c4..fb4087242 100644
--- a/api/src/Entity/Endpoint.php
+++ b/api/src/Entity/Endpoint.php
@@ -18,6 +18,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Serializer\Annotation\MaxDepth;
 use Symfony\Component\Validator\Constraints as Assert;
@@ -57,6 +58,8 @@
  *     "entities",
  *     "proxy"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Endpoint
 {
diff --git a/api/src/Entity/Entity.php b/api/src/Entity/Entity.php
index a3091daed..0826b08d7 100644
--- a/api/src/Entity/Entity.php
+++ b/api/src/Entity/Entity.php
@@ -19,6 +19,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use phpDocumentor\Reflection\Types\This;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Serializer\Annotation\MaxDepth;
 use Symfony\Component\Validator\Constraints as Assert;
@@ -63,6 +64,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Entity
 {
diff --git a/api/src/Entity/Gateway.php b/api/src/Entity/Gateway.php
index 723573295..9da2242f0 100644
--- a/api/src/Entity/Gateway.php
+++ b/api/src/Entity/Gateway.php
@@ -149,6 +149,7 @@
  * })
  *
  * @UniqueEntity("name")
+ * @UniqueEntity("reference")
  */
 class Gateway
 {
diff --git a/api/src/Entity/Mapping.php b/api/src/Entity/Mapping.php
index 6187d7fd4..ebf53a2bc 100644
--- a/api/src/Entity/Mapping.php
+++ b/api/src/Entity/Mapping.php
@@ -15,6 +15,7 @@
 use Doctrine\ORM\Mapping as ORM;
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Validator\Constraints as Assert;
 
@@ -44,6 +45,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Mapping
 {
diff --git a/api/src/Entity/Organization.php b/api/src/Entity/Organization.php
index cd231688b..8fd89a1bb 100644
--- a/api/src/Entity/Organization.php
+++ b/api/src/Entity/Organization.php
@@ -16,6 +16,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Serializer\Annotation\MaxDepth;
 use Symfony\Component\Validator\Constraints as Assert;
@@ -49,6 +50,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Organization
 {
diff --git a/api/src/Entity/SecurityGroup.php b/api/src/Entity/SecurityGroup.php
index ded4d2b26..457b35f2f 100644
--- a/api/src/Entity/SecurityGroup.php
+++ b/api/src/Entity/SecurityGroup.php
@@ -16,6 +16,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Serializer\Annotation\MaxDepth;
 use Symfony\Component\Validator\Constraints as Assert;
@@ -50,6 +51,8 @@
  *     "name": "exact",
  *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class SecurityGroup
 {
diff --git a/api/src/Entity/Template.php b/api/src/Entity/Template.php
index a400d7a1a..1041057f2 100644
--- a/api/src/Entity/Template.php
+++ b/api/src/Entity/Template.php
@@ -13,6 +13,7 @@
 use Doctrine\ORM\Mapping as ORM;
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Validator\Constraints as Assert;
 
@@ -41,8 +42,11 @@
  * @ApiFilter(DateFilter::class, strategy=DateFilter::EXCLUDE_NULL)
  * @ApiFilter(SearchFilter::class, properties={
  *     "supportedSchemas": "exact",
- *     "name": "exact"
+ *     "name": "exact",
+ *     "reference": "exact"
  * })
+ *
+ * @UniqueEntity("reference")
  */
 class Template
 {
diff --git a/api/src/Entity/User.php b/api/src/Entity/User.php
index 845610de9..1f26d4939 100644
--- a/api/src/Entity/User.php
+++ b/api/src/Entity/User.php
@@ -16,6 +16,7 @@
 use Gedmo\Mapping\Annotation as Gedmo;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidInterface;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Symfony\Component\Security\Core\User\PasswordAuthenticatedUserInterface;
 use Symfony\Component\Serializer\Annotation\Groups;
 use Symfony\Component\Serializer\Annotation\MaxDepth;
@@ -50,6 +51,8 @@
  *     "reference": "exact"
  * })
  *
+ * @UniqueEntity("reference")
+ *
  * @ORM\Table(name="`user`")
  */
 class User implements PasswordAuthenticatedUserInterface