Why are cropped parts of a PDF visible after bundling?

in Finalizing a briefOrganizing and editing exhibits

Adobe Acrobat and other PDF editors allow you to “crop” a PDF file, i.e. cut a PDF file to the desired size. This might appear to be an easy way to redact certain information at the margin of a PDF file. However, cropping does not delete this information but merely makes this part of the PDF file invisible. If you are submitting files electronically all this information would remain within the file. ExhibitManager ignores any cropping and will stamp the original PDF file.

If you wish to redact parts of a PDF file, we suggest using a professional redaction tool and then importing or linking the redacted file into ExhibitManager. If you do not have the required redaction tools, you might consider printing and re-scanning the PDF file.