diff --git a/src/main/java/de/metas/ui/web/window/descriptor/factory/standard/GridTabVOBasedDocumentEntityDescriptorFactory.java b/src/main/java/de/metas/ui/web/window/descriptor/factory/standard/GridTabVOBasedDocumentEntityDescriptorFactory.java
index 100edf841..0a5dd5d70 100644
--- a/src/main/java/de/metas/ui/web/window/descriptor/factory/standard/GridTabVOBasedDocumentEntityDescriptorFactory.java
+++ b/src/main/java/de/metas/ui/web/window/descriptor/factory/standard/GridTabVOBasedDocumentEntityDescriptorFactory.java
@@ -43,6 +43,7 @@
 import de.metas.ui.web.window.model.IDocumentFieldValueProvider;
 import de.metas.ui.web.window.model.lookup.LabelsLookup;
 import de.metas.ui.web.window.model.sql.SqlDocumentsRepository;
+import lombok.NonNull;
 
 /*
  * #%L
@@ -388,7 +389,7 @@ else if (actionType == ButtonFieldActionType.genericZoomInto)
 				//
 				.setReadonlyLogic(readonlyLogic)
 				.setAlwaysUpdateable(alwaysUpdateable)
-				.setMandatoryLogic(gridFieldVO.isMandatory() ? ConstantLogicExpression.TRUE : gridFieldVO.getMandatoryLogic())
+				.setMandatoryLogic(extractMandatoryLogic(gridFieldVO))
 				.setDisplayLogic(gridFieldVO.getDisplayLogic())
 				//
 				.setDefaultFilterField(gridFieldVO.isSelectionColumn())
@@ -631,6 +632,13 @@ private static boolean extractAlwaysUpdateable(final GridFieldVO gridFieldVO)
 		return gridFieldVO.isAlwaysUpdateable();
 	}
 
+	private static ILogicExpression extractMandatoryLogic(@NonNull final GridFieldVO gridFieldVO)
+	{
+		final ILogicExpression mandatoryLogic = gridFieldVO.getMandatoryLogic();
+
+		return mandatoryLogic.isNullExpression() ? ConstantLogicExpression.of(gridFieldVO.isMandatory()) : mandatoryLogic;
+	}
+	
 	private final void collectSpecialField(final DocumentFieldDescriptor.Builder field)
 	{
 		if (_specialFieldsCollector == null)
diff --git a/src/main/java/de/metas/ui/web/window/model/Document.java b/src/main/java/de/metas/ui/web/window/model/Document.java
index d12e85a32..1c3d00b26 100644
--- a/src/main/java/de/metas/ui/web/window/model/Document.java
+++ b/src/main/java/de/metas/ui/web/window/model/Document.java
@@ -1707,7 +1707,7 @@ public DocumentValidStatus checkAndGetValidStatus()
 				continue;
 			}
 
-			final DocumentValidStatus validState = documentField.updateStatusIfInvalidAndGet(changesCollector);
+			final DocumentValidStatus validState = documentField.updateStatusIfInitialInvalidAndGet(changesCollector);
 			if (!validState.isValid())
 			{
 				logger.trace("Considering document invalid because {} is not valid: {}", documentField, validState);
diff --git a/src/main/java/de/metas/ui/web/window/model/DocumentField.java b/src/main/java/de/metas/ui/web/window/model/DocumentField.java
index 9d1b61372..36b414524 100644
--- a/src/main/java/de/metas/ui/web/window/model/DocumentField.java
+++ b/src/main/java/de/metas/ui/web/window/model/DocumentField.java
@@ -490,7 +490,7 @@ public DocumentValidStatus getValidStatus()
 	}
 
 	@Override
-	public DocumentValidStatus updateStatusIfInvalidAndGet(final IDocumentChangesCollector changesCollector)
+	public DocumentValidStatus updateStatusIfInitialInvalidAndGet(final IDocumentChangesCollector changesCollector)
 	{
 		if (_validStatus.isInitialInvalid())
 		{
diff --git a/src/main/java/de/metas/ui/web/window/model/IDocumentField.java b/src/main/java/de/metas/ui/web/window/model/IDocumentField.java
index f270e24c0..dd0fb9766 100644
--- a/src/main/java/de/metas/ui/web/window/model/IDocumentField.java
+++ b/src/main/java/de/metas/ui/web/window/model/IDocumentField.java
@@ -86,7 +86,11 @@ default DocumentPath getDocumentPath()
 	@Override
 	DocumentValidStatus getValidStatus();
 
-	DocumentValidStatus updateStatusIfInvalidAndGet(IDocumentChangesCollector changesCollector);
+	/**
+	 * Note: it's not clear why it is enough to only evaluate the while the <i>initial</i> status is invalid..<br>
+	 * Yet I keep it that way for now, because it works as far as we see. And changing it might result in a performance degradation.
+	 */
+	DocumentValidStatus updateStatusIfInitialInvalidAndGet(IDocumentChangesCollector changesCollector);
 
 	IDocumentField copy(Document document, CopyMode copyMode);
 }