How to Flatten and Sanitize PDF Forms, Annotations & Signatures
Filled out an official application or contract form? Leaving AcroForm fields active allows recipients or third parties to alter entered text, modify check marks, or strip signatures. Flattening locks all form data permanently into the document canvas.
1. What Happens When a PDF is Flattened?
An interactive PDF form separates static page graphics from dynamic interactive widgets (/Annots and /AcroForm dictionaries). Flattening renders the appearance streams of all text inputs, checkboxes, and signatures directly into the page content stream (/Contents) and purges the editable widget dictionaries completely.
2. Removing Hidden Annotation Comments & Review History
PDFs shared during negotiation often retain internal reviewer comments, draft highlights, or sticky notes that should never reach the final client. Our sanitization tools strip confidential annotations while preserving pristine formatting.
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Frequently Asked Questions
Will flattening reduce the visual resolution of my document?▾
Not at all. Flattening merges vector objects into vector streams without rasterization. Text and lines remain 100% sharp for high-resolution commercial printing.
2run Engineering Team
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