Produce a signed, reproducible, no-PHI audit trail for an OpenMed de-identification run via deidentify(audit=True). Use when the user needs compliance evidence, a tamper-evident record of what was redacted and why, to verify nothing was changed, to retain proof for HIPAA/GDPR audits, or to review de-id decisions without exposing plaintext PHI. Covers the AuditReport / AuditSignature / AuditSpan / DetectorInfo fields, why audits store offsets+hashes+provenance+residual-risk and never plaintext, signing with .sign(key), and verifying with .verify(key). Pairs with OpenMed deidentifying-clinical-text and auditing-safe-harbor-checklist.