diff --git a/CHANGELOG.md b/CHANGELOG.md
index 14557c2..10d0b85 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+# 5.5.1 (2026-03-10)
+
+## Improvements
+
+- Ensure uniform annotation structures when records are stored.
+
+
 # 5.5.0 (2026-02-19)
 
 ## New features
diff --git a/dump_things_service/store/model_store.py b/dump_things_service/store/model_store.py
index 2af9c86..2242abc 100644
--- a/dump_things_service/store/model_store.py
+++ b/dump_things_service/store/model_store.py
@@ -98,13 +98,19 @@ class _ModelStore:
         submitter: str,
     ) -> None:
         """Add submitter IRI to the record annotations, use CURIE if possible"""
-        if 'annotations' not in json_object:
-            json_object['annotations'] = {}
+        json_object['annotations'] = self.homogenize_annotations(json_object)
         submitter_curie_or_iri = self.get_curie(self.tags['id'])
         time_curie_or_iri = self.get_curie(self.tags['time'])
         json_object['annotations'][submitter_curie_or_iri] = submitter
         json_object['annotations'][time_curie_or_iri] = datetime.now().isoformat()
 
+    @staticmethod
+    def homogenize_annotations(json_object) -> dict:
+        return {
+            k: v['annotation_value'] if isinstance(v, dict) else v
+            for k, v in json_object.get('annotations', {}).items()
+        }
+
     def get_curie(
         self,
         curie_or_iri: str,
diff --git a/pyproject.toml b/pyproject.toml
index 1d5d155..f852c96 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,7 +30,7 @@ dependencies = [
     "fastapi[standard]",
     "fastapi-pagination",
     "fsspec",
-    "linkml",
+    "linkml>=1.10.0",
     "pydantic",
     "PyYAML",
     "rdflib",