Masking occurs when key details in a PDF document are modified by placing a mask over the original information, and placing new information on top. 

When Inscribe detects signs that masking has occurred, the 'Masking issues' signal will appear in the Fraudulent Signals box. 

Clicking on the masking signal will display an image like the one below. The results are shown on a page-by-page basis, with masked regions highlighted in red.
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