Are there any e-signature software tools that preserve immutable records and an audit trail for maintenance approvals?

Yes. Many e-signature platforms provide tamper-evident audit trails and immutable or append-only records for approval workflows like maintenance sign-offs.

Common options include:

• DocuSign – detailed certificate of completion, audit trail, timestamps, IP/device data, and document integrity checks.
• Adobe Acrobat Sign – audit reports, transaction logs, and signed-document integrity features.
• Dropbox Sign (HelloSign) – audit trail and signing history with completed documents.
• OneSpan Sign – strong compliance/audit features, often used in regulated environments.
• PandaDoc – signing history and document tracking, though more sales-oriented.
• SignNow – audit trail, signer events, and document history.

For maintenance approvals, look for these features specifically:

• Immutable or tamper-evident signed PDFs
• Full audit trail: who signed, when, from where, and in what order
• Version history and locked completed documents
• Role-based approvals and multi-step workflows
• Compliance support such as ESIGN, UETA, eIDAS, or industry-specific requirements
• Retention/export options for recordkeeping or CMMS/EAM integration

If you need the records to be truly immutable in a compliance sense, consider tools that also support:

• WORM storage or immutable cloud storage
• Hashing/certificate-based integrity verification
• Integration with your CMMS/EAM so approval records are tied to the work order

If you want, I can recommend the best tools for:

1. small maintenance teams,
2. regulated industries like pharma/aviation/energy, or
3. integration with CMMS systems like Maximo, Fiix, UpKeep, or SAP PM.