PDF redaction guide
How to verify a redacted PDF on Mac
A black rectangle can look complete while text, comments, form values, metadata or attachments remain in the file. Verification begins with the exported PDF itself and ends with explicit limits.
1. Preserve the exact source
Record a SHA-256 hash before inspection and never overwrite the reviewed file. A screenshot cannot establish which PDF was checked; a hash keeps the receipt tied to the source bytes.
2. Inventory recoverable objects
Inspect extractable text, standard metadata, XMP markers, comments, forms and embedded files. These objects can survive even when the visible page appears redacted.
3. Check bounded visual covers
Where the file exposes a Redact annotation or a dark Square annotation, inspect the region for recoverable text. Treat the result as bounded evidence, not proof about every visual mark.
4. Keep unknowns visible
Encrypted files, images, flattened marks, custom encodings and unsupported objects need separate review. Never convert a missing observation into a pass.
5. Export the evidence
Retain the source hash, findings, limitations and any copy hash together. Qualified reviewers still decide whether the disclosure risk and legal process are acceptable.