diff --git a/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Oaf.java b/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Oaf.java
index 3496492e8..fef32c0c6 100644
--- a/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Oaf.java
+++ b/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Oaf.java
@@ -2,8 +2,12 @@
 package eu.dnetlib.dhp.schema.oaf;
 
 import java.io.Serializable;
+import java.util.Collection;
 import java.util.List;
 import java.util.Objects;
+import java.util.Optional;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public abstract class Oaf implements Serializable {
 
@@ -40,9 +44,35 @@ public abstract class Oaf implements Serializable {
 		this.lastupdatetimestamp = lastupdatetimestamp;
 	}
 
-	public void mergeOAFDataInfo(Oaf e) {
-		if (e.getDataInfo() != null && compareTrust(this, e) < 0)
-			dataInfo = e.getDataInfo();
+	public void mergeFrom(Oaf o) {
+		if (Objects.isNull(o)) {
+			return;
+		}
+		setCollectedfrom(
+				Stream
+						.concat(
+								Optional
+										.ofNullable(getCollectedfrom())
+										.map(Collection::stream)
+										.orElse(Stream.empty()),
+								Optional
+										.ofNullable(o.getCollectedfrom())
+										.map(Collection::stream)
+										.orElse(Stream.empty()))
+						.distinct() // relies on KeyValue.equals
+						.collect(Collectors.toList()));
+
+		mergeOAFDataInfo(o);
+
+		setLastupdatetimestamp(
+				Math.max(
+					Optional.ofNullable(getLastupdatetimestamp()).orElse(0L),
+					Optional.ofNullable(o.getLastupdatetimestamp()).orElse(0L)));
+	}
+
+	public void mergeOAFDataInfo(Oaf o) {
+		if (o.getDataInfo() != null && compareTrust(this, o) < 0)
+			dataInfo = o.getDataInfo();
 	}
 
 	protected String extractTrust(Oaf e) {
@@ -62,7 +92,7 @@ public abstract class Oaf implements Serializable {
 		if (o == null || getClass() != o.getClass())
 			return false;
 		Oaf oaf = (Oaf) o;
-		return Objects.equals(dataInfo, oaf.dataInfo)
+		return Objects.equals(getDataInfo(), oaf.getDataInfo())
 			&& Objects.equals(lastupdatetimestamp, oaf.lastupdatetimestamp);
 	}
 
diff --git a/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/OafEntity.java b/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/OafEntity.java
index 2823ee49d..17c3e6bdd 100644
--- a/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/OafEntity.java
+++ b/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/OafEntity.java
@@ -78,14 +78,10 @@ public abstract class OafEntity extends Oaf implements Serializable {
 	}
 
 	public void mergeFrom(OafEntity e) {
-
-		if (e == null)
-			return;
+		super.mergeFrom(e);
 
 		originalId = mergeLists(originalId, e.getOriginalId());
 
-		collectedfrom = mergeLists(collectedfrom, e.getCollectedfrom());
-
 		pid = mergeLists(pid, e.getPid());
 
 		if (e.getDateofcollection() != null && compareTrust(this, e) < 0)
diff --git a/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Relation.java b/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Relation.java
index 17a50d7ac..0de34dbec 100644
--- a/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Relation.java
+++ b/dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/oaf/Relation.java
@@ -130,19 +130,7 @@ public class Relation extends Oaf {
 			Objects.equals(getSubRelType(), r.getSubRelType()), "subRelType(s) must be equal");
 		checkArgument(Objects.equals(getRelClass(), r.getRelClass()), "relClass(es) must be equal");
 
-		setCollectedfrom(
-			Stream
-				.concat(
-					Optional
-						.ofNullable(getCollectedfrom())
-						.map(Collection::stream)
-						.orElse(Stream.empty()),
-					Optional
-						.ofNullable(r.getCollectedfrom())
-						.map(Collection::stream)
-						.orElse(Stream.empty()))
-				.distinct() // relies on KeyValue.equals
-				.collect(Collectors.toList()));
+		super.mergeFrom(r);
 	}
 
 	@Override