diff --git a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/AbstractMdRecordToOafMapper.java b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/AbstractMdRecordToOafMapper.java
index 0a32766c9..cdc707084 100644
--- a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/AbstractMdRecordToOafMapper.java
+++ b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/AbstractMdRecordToOafMapper.java
@@ -143,7 +143,7 @@ public abstract class AbstractMdRecordToOafMapper {
 			return createOafs(doc, type, instances, collectedFrom, info, lastUpdateTimestamp);
 		} catch (DocumentException e) {
 			log.error("Error with record:\n" + xml);
-			return null;
+			return Lists.newArrayList();
 		}
 	}
 
diff --git a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/GenerateEntitiesApplication.java b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/GenerateEntitiesApplication.java
index 290a22656..06d5e9acb 100644
--- a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/GenerateEntitiesApplication.java
+++ b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/GenerateEntitiesApplication.java
@@ -150,8 +150,8 @@ public class GenerateEntitiesApplication {
 						.sequenceFile(sp, Text.class, Text.class)
 						.map(k -> new Tuple2<>(k._1().toString(), k._2().toString()))
 						.map(k -> convertToListOaf(k._1(), k._2(), shouldHashId, vocs))
-						.filter(Objects::nonNull)
-						.flatMap(List::iterator));
+						.flatMap(List::iterator)
+						.filter(Objects::nonNull));
 		}
 
 		switch (mode) {
@@ -225,7 +225,8 @@ public class GenerateEntitiesApplication {
 		final boolean shouldHashId,
 		final VocabularyGroup vocs) {
 
-		if (Objects.isNull(convertToListOaf(id, s, shouldHashId, vocs))) {
+		final List<Oaf> oaf = convertToListOaf(id, s, shouldHashId, vocs);
+		if (Optional.ofNullable(oaf).map(List::isEmpty).orElse(false)) {
 			return s;
 		}
 		return null;
@@ -235,8 +236,7 @@ public class GenerateEntitiesApplication {
 		try {
 			return OBJECT_MAPPER.readValue(s, clazz);
 		} catch (final Exception e) {
-			log.error("Error parsing object of class: {}", clazz);
-			log.error(s);
+			log.error("Error parsing object of class: {}:\n{}", clazz, s);
 			throw new IllegalArgumentException(e);
 		}
 	}
diff --git a/dhp-workflows/dhp-graph-mapper/src/test/java/eu/dnetlib/dhp/oa/graph/raw/MappersTest.java b/dhp-workflows/dhp-graph-mapper/src/test/java/eu/dnetlib/dhp/oa/graph/raw/MappersTest.java
index 390920027..506a69012 100644
--- a/dhp-workflows/dhp-graph-mapper/src/test/java/eu/dnetlib/dhp/oa/graph/raw/MappersTest.java
+++ b/dhp-workflows/dhp-graph-mapper/src/test/java/eu/dnetlib/dhp/oa/graph/raw/MappersTest.java
@@ -926,11 +926,12 @@ class MappersTest {
 	}
 
 	@Test
-	void testNotWellFormed() throws IOException, DocumentException {
+	void testNotWellFormed() throws IOException {
 		final String xml = IOUtils
 			.toString(Objects.requireNonNull(getClass().getResourceAsStream("oaf_notwellformed.xml")));
-		assertEquals(null, new OafToOafMapper(vocs, false, true).processMdRecord(xml));
-
+		final List<Oaf> actual = new OafToOafMapper(vocs, false, true).processMdRecord(xml);
+		assertNotNull(actual);
+		assertTrue(actual.isEmpty());
 	}
 
 	private void assertValidId(final String id) {