diff --git a/.spectral.yml b/.spectral.yml
new file mode 100644
index 0000000000000000000000000000000000000000..57f5debabc2b2e67d6eca9a971712b5f1b4dbbcb
--- /dev/null
+++ b/.spectral.yml
@@ -0,0 +1,5 @@
+extends:
+  - spectral:oas
+#  - https://italia.github.io/api-oas-checker/spectral.yml
+#  - https://italia.github.io/api-oas-checker/spectral-generic.yml
+  - https://italia.github.io/api-oas-checker/spectral-security.yml
diff --git a/reference/1_sender.json b/reference/1_sender.json
index c85cb629f3956d984b5f987f5c1f5e220d71b938..b65024003a40a961fcd84df74d6e9f3bbb875f02 100644
--- a/reference/1_sender.json
+++ b/reference/1_sender.json
@@ -474,6 +474,8 @@
                     },
                     "history": {
                       "type": "array",
+                      "maxItems": 3,
+                      "minItems": 0,
                       "items": {
                         "$ref": "../models/status-overview.json"
                       }
diff --git a/reference/2_subscriber.json b/reference/2_subscriber.json
index dc70fc582070ec815ddfde885ea4d919e73242d3..d8e410824e3c43231058d5f196eeda5a8a978cd5 100644
--- a/reference/2_subscriber.json
+++ b/reference/2_subscriber.json
@@ -64,6 +64,29 @@
                               ],
                               "email": "behoerde@example.com"
                             }
+                          }
+                        ],
+                        "schemas": [
+                          {
+                            "mimeType": "json",
+                            "schemaSource": "none",
+                            "encoding": "plain"
+                          }
+                        ],
+                        "callback": {
+                          "callbackURI": "http://127.0.0.1:4010/voluptas"
+                        },
+                        "destinationId": "0ddf3ab5-dd89-4e04-9ecd-b2c50b0b4efd"
+                      },
+                      {
+                        "publicOrganization": {
+                          "organizationName": "Gewerbeamt Musterstadt",
+                          "address": {
+                            "type": "national",
+                            "street": "Kurzer Weg",
+                            "houseNumber": "7",
+                            "postalCode": "12345",
+                            "city": "Ankh-Morpork"
                           },
                           "technicalContact": [
                             {
@@ -120,44 +143,21 @@
                               ],
                               "email": "behoerde@example.com"
                             }
-                          },
-                          "technicalContact": [
-                            {
-                              "formOfAddress": "Herr",
-                              "doctoralDegrees": "Dr.",
-                              "firstName": "Kunibert",
-                              "lastName": "Vonundzu",
-                              "contact": {
-                                "telephones": [
-                                  {
-                                    "number": "+49 89 32168-42",
-                                    "mobile": false,
-                                    "description": "work"
-                                  },
-                                  {
-                                    "number": "+49 123 456789",
-                                    "mobile": true,
-                                    "description": "work"
-                                  }
-                                ],
-                                "email": "kunibert.vonundzu@example.com"
-                              }
-                            }
-                          ],
-                          "schemas": [
-                            {
-                              "mimeType": "json",
-                              "schemaSource": "none",
-                              "encoding": "plain"
-                            }
-                          ],
-                          "callback": {
-                            "callbackURI": "http://127.0.0.1:4010/voluptas"
-                          },
-                          "destinationId": "7881dba9-4055-4854-8b6d-11ea5b7f3047"
-                        }
-                      ]
-                    }
+                          }
+                        ],
+                        "schemas": [
+                          {
+                            "mimeType": "json",
+                            "schemaSource": "none",
+                            "encoding": "plain"
+                          }
+                        ],
+                        "callback": {
+                          "callbackURI": "http://127.0.0.1:4010/voluptas"
+                        },
+                        "destinationId": "7881dba9-4055-4854-8b6d-11ea5b7f3047"
+                      }
+                    ]
                   }
                 }
               }