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Secondments, contractors, joint ventures, agency partners — cross-organization personnel movement is daily reality in financial services. Are you still running employees who hold valid credentials and legitimate access to both organizations' customer data on logs that can be disputed?
When an incident surfaces, can your organization prove who accessed what, and when, in a matter of hours?
- CISOs and compliance leads at financial institutions operating secondment, contractor, or agency partner models
- Information security leads responding to amended APPI, FSA cybersecurity guidelines, data residency requirements, and extraterritorial GDPR application
- Security teams who have deployed DLP and SIEM but still face the question of log integrity itself
- Teams that want regulatory audit responses measured in hours, not weeks
How Lemma approaches it
Lemma generates a ZK proof for every cross-organization data access and anchors the commitment on-chain. Customer data itself never leaves your perimeter — only the fact of who accessed what, and when, becomes independently verifiable by the originating organization, the receiving organization, and the regulator.
DLP detects anomalies. SIEM aggregates logs. Lemma provides the layer underneath: tamper-evidence on the logs themselves, and a shared truth layer across organizational boundaries. Lemma fills the structural gap that has existed between detection and audit.
Where this layer can be slotted into your secondment, contractor, or agency partner model is something we can map out in a first conversation.
Lemma Discovery Call — Start with a 30-minute conversation
Tell us the shape of the problem you're working on. We'll explore together whether Lemma's verification layer could fit. No technical details or sensitive information required.
If we see a fit, we move to NDA and then into industry-specific materials, reference architecture, and PoC design.
A real-world example
In 2026, an insurance company seconding employees to agency partners (regional banks and securities firms) lost 2,476 customer records across 36 partner offices (MetLife Japan). The incident is a textbook case of the structural gap.
The root cause is straightforward: an ambiguous trust boundary operated on mutable logs. Access looked legitimate, logs were post-hoc editable, and there was no shared truth layer between origin and receiver. DLP and SIEM could detect anomalies, but no mechanism existed to fix detected events as tamper-evident facts.
Detailed timeline analysis, before-and-after comparison, and regulatory response time estimates are shared in the industry-specific kit we send after the consultation call.
Architecture in concept
Lemma does not replace your existing systems. We place an attestation gateway between users and your CRM/database — one extra layer.
Data itself is never touched. Only the fact of access is cryptographically attested. Because the proof is zero-knowledge, the access content (customer information) is never exposed. Anchoring the commitment on-chain makes any post-hoc modification detectable. Origin, receiver, and regulator can each verify independently.
The four implementation layers (ENCRYPT / PROVE / DISCLOSE / PROVENANCE) and integration patterns with existing stacks are detailed in the whitepaper and in the post-call technical kit.
What Lemma cryptographically guarantees
- The actor, target record, timestamp, and type of every access event
- Tamper-evidence on the access trail
- No exposure of data content (no PII leaks from the attestation itself)
- Independent verification by origin, receiver, and regulator
Ready to prove?
Talk to us about your use case. We respond within one business day.