diff --git a/dhp-common/src/main/java/eu/dnetlib/dhp/schema/oaf/utils/GraphCleaningFunctions.java b/dhp-common/src/main/java/eu/dnetlib/dhp/schema/oaf/utils/GraphCleaningFunctions.java
index 7af85fc4a..2ba805e1e 100644
--- a/dhp-common/src/main/java/eu/dnetlib/dhp/schema/oaf/utils/GraphCleaningFunctions.java
+++ b/dhp-common/src/main/java/eu/dnetlib/dhp/schema/oaf/utils/GraphCleaningFunctions.java
@@ -228,20 +228,20 @@ public class GraphCleaningFunctions extends CleaningFunctions {
 	}
 
 	public static <T extends Oaf> boolean filter(T value) {
-		if (Boolean.TRUE
-			.equals(
-				Optional
-					.ofNullable(value)
-					.map(
-						o -> Optional
-							.ofNullable(o.getDataInfo())
-							.map(
-								d -> Optional
-									.ofNullable(d.getInvisible())
-									.orElse(true))
-							.orElse(false))
-					.orElse(true))) {
-			return true;
+		if (!(value instanceof Relation) && (Boolean.TRUE
+				.equals(
+					Optional
+						.ofNullable(value)
+						.map(
+							o -> Optional
+								.ofNullable(o.getDataInfo())
+								.map(
+									d -> Optional
+										.ofNullable(d.getInvisible())
+										.orElse(true))
+								.orElse(false))
+						.orElse(true)))) {
+				return true;
 		}
 
 		if (value instanceof Datasource) {