diff --git a/CHANGELOG.md b/CHANGELOG.md
index 97207e2c..82a89f4d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- make altLabel property for vocabularies always a list
+
 ### Security
 
 ## [3.5.0] - 2025-01-29
diff --git a/mex/model/vocabularies/api-type.json b/mex/model/vocabularies/api-type.json
index 530d859b..fa5e2e9a 100644
--- a/mex/model/vocabularies/api-type.json
+++ b/mex/model/vocabularies/api-type.json
@@ -1,9 +1,11 @@
 [
     {
-        "altLabel": {
-            "de": "RESTful API",
-            "en": "RESTful API"
-        },
+        "altLabel": [
+            {
+                "de": "RESTful API",
+                "en": "RESTful API"
+            }
+        ],
         "definition": {
             "de": "Representational State Transfer: Softwarearchitektur verteilter Systemen, insbesondere für Webservices.",
             "en": "Representational State Transfer: Software architectural style for decoupled components, especially web services."
diff --git a/mex/model/vocabularies/bibliographic-resource-type.json b/mex/model/vocabularies/bibliographic-resource-type.json
index 972acee1..23bd8616 100644
--- a/mex/model/vocabularies/bibliographic-resource-type.json
+++ b/mex/model/vocabularies/bibliographic-resource-type.json
@@ -1,9 +1,11 @@
 [
     {
-        "altLabel": {
-            "de": "Monografie",
-            "en": "Monograph"
-        },
+        "altLabel": [
+            {
+                "de": "Monografie",
+                "en": "Monograph"
+            }
+        ],
         "definition": {
             "de": "Eine Monographie.",
             "en": "A monograph."
@@ -21,9 +23,11 @@
         }
     },
     {
-        "altLabel": {
-            "en": "Book section"
-        },
+        "altLabel": [
+            {
+                "en": "Book section"
+            }
+        ],
         "definition": {
             "de": "Ein Teil eines Buches.",
             "en": "One of the sections into which a book is divided."
@@ -56,10 +60,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Doktorarbeit",
-            "en": "Doctoral dissertation"
-        },
+        "altLabel": [
+            {
+                "de": "Doktorarbeit",
+                "en": "Doctoral dissertation"
+            }
+        ],
         "closeMatch": [
             "http://purl.org/ontology/bibo/Thesis"
         ],
@@ -78,10 +84,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Habilitation",
-            "en": "Postdoctoral thesis"
-        },
+        "altLabel": [
+            {
+                "de": "Habilitation",
+                "en": "Postdoctoral thesis"
+            }
+        ],
         "closeMatch": [
             "http://purl.org/ontology/bibo/Thesis"
         ],
@@ -100,9 +108,11 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Wissenschaftliche Fachzeitschrift"
-        },
+        "altLabel": [
+            {
+                "de": "Wissenschaftliche Fachzeitschrift"
+            }
+        ],
         "definition": {
             "de": "Zeitschrift, die regelmäßig wissenschaftliche Forschungsergebnisse veröffentlicht.",
             "en": "Periodical journal publishing scientific research."
@@ -118,10 +128,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Wissenschaftlicher Artikel",
-            "en": "Paper"
-        },
+        "altLabel": [
+            {
+                "de": "Wissenschaftlicher Artikel",
+                "en": "Paper"
+            }
+        ],
         "definition": {
             "de": "Beitrag, der in einer wissenschaftlichen Zeitschrift veröffentlicht wurde.",
             "en": "Article published in an academic journal."
@@ -149,9 +161,11 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Plakat"
-        },
+        "altLabel": [
+            {
+                "de": "Plakat"
+            }
+        ],
         "definition": {
             "de": "Eine Plakat mit ein Thema auf einer wissenschaftlichen Veranstaltung vermittelt wird.",
             "en": "A type of graphical image created to promote a topic on a scientific event."
@@ -183,10 +197,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Vortrag",
-            "en": "Talk"
-        },
+        "altLabel": [
+            {
+                "de": "Vortrag",
+                "en": "Talk"
+            }
+        ],
         "definition": {
             "de": "Vortrag über ein Thema in begrenzter Zeit.",
             "en": "Process of presenting a topic to an audience."
@@ -229,10 +245,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Studienabschlussarbeit",
-            "en": "Academic thesis"
-        },
+        "altLabel": [
+            {
+                "de": "Studienabschlussarbeit",
+                "en": "Academic thesis"
+            }
+        ],
         "definition": {
             "de": "Schriftliche Abschlussarbeit eines Studiengangs an einer Hochschule oder Berufsakademie",
             "en": "General term for a document submitted in support of candidature for an academic degree."
diff --git a/mex/model/vocabularies/data-processing-state.json b/mex/model/vocabularies/data-processing-state.json
index ed0ccf28..6ea10df7 100644
--- a/mex/model/vocabularies/data-processing-state.json
+++ b/mex/model/vocabularies/data-processing-state.json
@@ -1,9 +1,11 @@
 [
     {
-        "altLabel": {
-            "de": "Primärdaten",
-            "en": "primary data"
-        },
+        "altLabel": [
+            {
+                "de": "Primärdaten",
+                "en": "primary data"
+            }
+        ],
         "definition": {
             "de": "Rohdaten oder Primärdaten sind diejenigen Daten, die bei einer Beobachtung, einer Messung oder einer Datenerhebung unmittelbar gewonnen werden und die noch unbearbeitet vorliegen.",
             "en": "Raw data or primary data are those data that are directly obtained during an observation, a measurement or a data collection and that are still available unprocessed."
diff --git a/mex/model/vocabularies/language.json b/mex/model/vocabularies/language.json
index aaef526e..c6b580e3 100644
--- a/mex/model/vocabularies/language.json
+++ b/mex/model/vocabularies/language.json
@@ -1,9 +1,11 @@
 [
     {
-        "altLabel": {
-            "de": "de",
-            "en": "de"
-        },
+        "altLabel": [
+            {
+                "de": "de",
+                "en": "de"
+            }
+        ],
         "exactMatch": "",
         "identifier": "https://mex.rki.de/item/language-1",
         "inScheme": "https://mex.rki.de/item/language",
@@ -13,10 +15,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "en",
-            "en": "en"
-        },
+        "altLabel": [
+            {
+                "de": "en",
+                "en": "en"
+            }
+        ],
         "exactMatch": "",
         "identifier": "https://mex.rki.de/item/language-2",
         "inScheme": "https://mex.rki.de/item/language",
@@ -26,10 +30,12 @@
         }
     },
     {
-        "altLabel": {
-            "de": "fr",
-            "en": "fr"
-        },
+        "altLabel": [
+            {
+                "de": "fr",
+                "en": "fr"
+            }
+        ],
         "exactMatch": "",
         "identifier": "https://mex.rki.de/item/language-3",
         "inScheme": "https://mex.rki.de/item/language",
diff --git a/mex/model/vocabularies/license.json b/mex/model/vocabularies/license.json
index 7c45bf9b..681bbe9c 100644
--- a/mex/model/vocabularies/license.json
+++ b/mex/model/vocabularies/license.json
@@ -1,9 +1,11 @@
 [
     {
-        "altLabel": {
-            "de": "CC-BY-4.0",
-            "en": "CC-BY-4.0"
-        },
+        "altLabel": [
+            {
+                "de": "CC-BY-4.0",
+                "en": "CC-BY-4.0"
+            }
+        ],
         "exactMatch": [
             "https://creativecommons.org/licenses/by/4.0/legalcode"
         ],
diff --git a/mex/model/vocabularies/resource-type-general.json b/mex/model/vocabularies/resource-type-general.json
index 5c8b83e3..141f3bd5 100644
--- a/mex/model/vocabularies/resource-type-general.json
+++ b/mex/model/vocabularies/resource-type-general.json
@@ -40,9 +40,11 @@
         }
     },
     {
-        "altLabel": {
-            "de": "Bild"
-        },
+        "altLabel": [
+            {
+                "de": "Bild"
+            }
+        ],
         "identifier": "https://mex.rki.de/item/resource-type-general-16",
         "inScheme": "https://mex.rki.de/item/resource-type-general",
         "prefLabel": {