diff --git a/pipeline/src/base.py b/pipeline/src/base.py
index 47d4d703..5bb2f275 100644
--- a/pipeline/src/base.py
+++ b/pipeline/src/base.py
@@ -92,6 +92,17 @@ def to_jsonld(self, include_empty_properties=True, embed_linked_nodes=True, with
                             )
                             for item in value
                         ]
+                elif isinstance(value, (tuple, list)):
+                    # if property.multiple is False, then this means the node does not validate,
+                    # but we should try to serialize it anyway
+                    data[property.path] = [
+                        value_to_jsonld(
+                            item,
+                            include_empty_properties=include_empty_properties,
+                            embed_linked_nodes=embed_linked_nodes,
+                        )
+                        for item in value
+                    ]
                 else:
                     data[property.path] = value_to_jsonld(
                         value,
diff --git a/pipeline/src/properties.py b/pipeline/src/properties.py
index ba432353..ad730392 100644
--- a/pipeline/src/properties.py
+++ b/pipeline/src/properties.py
@@ -194,7 +194,7 @@ def deserialize_item(item):
             else:
                 raise NotImplementedError()
 
-        if self.multiple and isinstance(data, (tuple, list)):
+        if isinstance(data, (tuple, list)):
             return [deserialize_item(item) for item in data]
         else:
             return deserialize_item(data)
diff --git a/pipeline/tests/test_regressions.py b/pipeline/tests/test_regressions.py
index 2c750a94..595b70b2 100644
--- a/pipeline/tests/test_regressions.py
+++ b/pipeline/tests/test_regressions.py
@@ -235,3 +235,22 @@ def test_issue0023():
     assert len(dv_again.custodians[0].affiliations) == 2
     assert dv_again.custodians[0].affiliations[0].member_of.full_name == "University of This Place"
     assert dv_again.custodians[0].affiliations[1].member_of.full_name == "University of That Place"
+
+
+def test_issue0056():
+    # https://github.com/openMetadataInitiative/openMINDS_Python/issues/56
+    # Since we are permissive on object creation, serialization to JSON-LD should work
+    # even if the object gives validation failures.
+    # However, under some circumstances, to_jsonld() produces a data structure
+    # that cannot be saved as a JSON string.
+    dataset = omcore.Dataset(
+        digital_identifier=[
+            omcore.DOI(identifier="abc"),
+            omcore.DOI(identifier="def")
+        ]
+    )
+    failures = dataset.validate(ignore=["required"])
+    assert len(failures) == 1
+    assert failures["multiplicity"] == ['digital_identifier does not accept multiple values, but contains 2']
+    data = dataset.to_jsonld()
+    json.dumps(data)  # this should not raise an Exception