diff --git a/src/utils.js b/src/utils.js
index e0648f77f2530360224055701e23e9a4981fda47..603d5c8a9ba56a05c77bef4cb3fa38f85b826565 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -230,7 +230,7 @@ export const addKeyValuePdfAnnotationsToAnnotationFactory = (annotationFactory,
 
     // add machine readable annotation
     author = 'Maschinell aufgebracht, bitte nicht entfernen / Applied automatically, please do not remove';
-    content = 'dbp-annotation-' + annotationType + '-' + organizationNumber + '=' + value;
+    content = 'dbp_annotation_' + annotationType + '_' + organizationNumber + '=' + value;
     annotationFactory = addPdfAnnotationToAnnotationFactory(annotationFactory, author, content);
 
     return annotationFactory;