You drew black rectangles over the sensitive parts. Looks redacted. But anyone who selects the text underneath the black boxes can copy what you 'hid'. Or worse, your viewer doesn't even render the boxes consistently.
This is the most consequential PDF problem you can have. The redaction is fake.
What's actually going wrong
A black rectangle placed over text doesn't remove the text. The text remains in the file's content layer, hidden visually but extractable via selection, search, or any tool that reads the PDF structure.
True redaction removes the underlying content — replacing it with permanent black bars or simply deleting it. The information leaves the file entirely.
The quick fix
Use Flint's redact PDF tool. Select the content to redact. Flint applies true redaction — content is removed from the file, replaced with permanent visual marks. The 'redacted' material can't be recovered from the file.
Verify by trying to select text in the redacted area. If you can't select, the redaction is real. If selection works, the underlying text is still there.
If that didn't work
For PDFs where you already shipped fake redaction, the damage is done. Anyone with the file can recover the 'hidden' content. Treat the content as published.
Replace future redactions with proper tools. Audit past redacted files for accidental leaks.
Prevent it next time
Never use rectangle annotations for redaction. Never rely on visual cover. Always use dedicated redaction tools that remove content. And test redactions by attempting to recover the redacted content before sharing.
FAQ
How do I verify a redaction is real?
Try selecting text in the redacted area. If selection produces no text or just whitespace, redaction is real. If you can select and copy the 'hidden' text, redaction is fake.
Can I undo a real redaction?
No — true redaction removes content permanently. Keep an unredacted master copy for your records; redact only the distributed version.
Why is fake redaction so common?
Tools make it easy to draw black rectangles; few users know that doesn't actually redact. The visual result looks identical to real redaction, so the gap goes unnoticed until someone extracts.
Are there legal implications?
Yes — fake redactions have caused major data breaches, including high-profile government and corporate cases. Take it seriously, especially for legally-sensitive material.
Real redaction is non-negotiable for sensitive content. Use Flint's redact tool — proper removal, not cosmetic cover.