diff --git a/src/UglyToad.PdfPig/Parser/CatalogFactory.cs b/src/UglyToad.PdfPig/Parser/CatalogFactory.cs
index da2bb2cc..dd31ae59 100644
--- a/src/UglyToad.PdfPig/Parser/CatalogFactory.cs
+++ b/src/UglyToad.PdfPig/Parser/CatalogFactory.cs
@@ -102,8 +102,8 @@
 
             do
             {
-                var current = toProcess.Dequeue();
-
+                var current = toProcess.Dequeue();
+                if (current.reference.GetHashCode() == current.parentReference.GetHashCode()) { continue; } // Issue #519
                 if (!current.nodeDictionary.TryGet(NameToken.Kids, pdfTokenScanner, out ArrayToken kids))
                 {
                     if (!isLenientParsing)