Every invoice, fully accounted for.
Cortena keeps a complete audit trail on every invoice. Who captured it, what the agent coded, what a person changed, who approved it, when it was exported. Built for operators and auditors alike.
The record cannot quietly change.
The original document stays linked to the booking, and every version is kept.
When an invoice is exported, its state is sealed. The original file (PDF, image or e-invoice) is stored next to the booking data with a content hash, so anyone can confirm nothing was swapped after the fact. Earlier versions are never deleted. They become part of the history.
Supplier line reads "cable and wiring material". The last three invoices from this supplier were coded to 6845. Anna moved it to 6835 to match this project's cost split.
Overrides keep the reasoning.
When a person changes an AI suggestion, the original suggestion is preserved.
Cortena codes every line and shows why. If your team overrides a value, the human decision stands, but the original AI suggestion and the reason behind it are kept on the record. An auditor can see both the final value and what the agent proposed, without asking anyone to reconstruct it from memory.
Built to help you work GoBD-aligned.
Cortena is built around the GoBD principles for how accounting records should be traceable and unchangeable. We give you the trail. Your tax advisor confirms the setup.
Traceability
Every invoice carries a complete, timestamped log from capture to export, so any booking can be traced back to its source document and the people who touched it.
Immutability
Exported records are sealed and versioned. Earlier states are never overwritten, and the original document is stored with a content hash.
Completeness
Duplicate detection and per-tenant mailboxes are designed so invoices are captured once and nothing is silently dropped along the way.
Timeliness
Events are logged as they happen, with real timestamps, so the record reflects when work was actually done rather than when it was written up.
Cortena is GoBD-aligned, not GoBD-certified. Long-term archiving still happens in DATEV Unternehmen online or your document management system. Cortena provides the audit trail and the sealed export; the certified archive lives where your accounting is kept.
Built for GDPR and DSGVO.
Cortena processes personal data on your behalf as a processor. You stay the controller, and we bring the agreements, the roles and the controls to meet your obligations.
Cortena acts as your data processor under the GDPR. You remain the controller and decide what is processed and why.
A GDPR and DSGVO-aligned data processing agreement is available on request, covering security, sub-processors and transfer safeguards.
We have appointed a data protection officer you can reach directly at dpo@cortena.ai for any privacy question.
Personal data is processed in the EU. Sub-processors are kept within the EU wherever possible, with the current list available on request.
Where your records live.
The audit trail is only as trustworthy as where it is stored. Here are the plain facts.
All data is hosted in Hetzner data centres in Germany, inside the EU.
Records and documents are encrypted at rest with AES-256, and in transit over TLS.
Your invoices and data are never used to train AI models. They stay yours.
GDPR-ready with a data processing agreement, so your compliance team has what it needs.
Audit trail questions, answered.
No. Cortena is GoBD-aligned, not certified. It is built around the GoBD principles of traceability and immutability and gives you a complete audit trail, but the certified archive stays in DATEV Unternehmen online or your DMS. Your tax advisor confirms the overall setup.
Every event on an invoice: capture, AI coding, each human edit with who made it, duplicate checks, approvals with the applied rule, and the export. Each event has a real timestamp and is attributed to a person or the agent.
It is preserved. The human value becomes the final one, but the original AI suggestion and the reasoning behind it stay on the invoice. An auditor can see both without reconstructing anything.
No. Once an invoice is exported, its state is sealed and versioned, and the original document is stored with a content hash. Corrections create a new version rather than overwriting history.
In Hetzner data centres in Germany, inside the EU. Records are encrypted at rest with AES-256 and in transit over TLS, and your data is never used to train AI models.
No. Long-term archiving stays in DATEV Unternehmen online or your document management system. Cortena provides the audit trail and the sealed, booking-ready export that flows into that archive.
- Still have a question?
See the trail on a real invoice.
Book a demo and we will walk one of your invoices from mailbox to sealed export.
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