diff --git a/library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDVisualizer.java b/library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDVisualizer.java
index c9431b2b..4aa8a374 100644
--- a/library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDVisualizer.java
+++ b/library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDVisualizer.java
@@ -332,7 +332,7 @@ public class ZUGFeRDVisualizer {
 
 		FOUserAgent userAgent = fopFactory.newFOUserAgent();
 
-		userAgent.getRendererOptions().put("pdf-a-mode", "PDF/A-1b");
+		userAgent.getRendererOptions().put("pdf-a-mode", "PDF/A-3b");
 
 // Step 2: Set up output stream.
 // Note: Using BufferedOutputStream for performance reasons (helpful with FileOutputStreams).