Since early 2026, Anthropic has expanded Claude with legal functions and plugins. The appeal for law firms is clear: legal work involves long documents, many dependencies and language where detail matters. Before client data enters an AI system, however, a different question comes first: may a German lawyer make that information available to an external AI service?
Yes, using Claude can be permissible. A standard chat subscription does not automatically meet the requirements.
Section 203 of the German Criminal Code does not impose a blanket ban on external IT providers. It allows other participating persons to be involved where their access is necessary for the service. A law firm must also address Section 43e BRAO, the GDPR and appropriate technical safeguards. The decisive factors are the specific product, configuration and contracts - not the product name alone.
Why Claude is attractive for legal work
Claude is designed to work with large amounts of text. Contracts, bundles of briefs and files can be analysed as a whole without breaking the context into small fragments too early. That can be valuable for:
- structured summaries of lengthy documents,
- comparisons between contract versions and reference documents,
- initial identification of risks or missing provisions, and
- drafting suggestions that are then reviewed by a lawyer.
The model does not replace legal responsibility or professional review. Anthropic's own commercial terms state that outputs may be incomplete or inaccurate and must be assessed before use.
What Section 203 StGB and Section 43e BRAO require
Section 203 StGB protects secrets entrusted to lawyers or otherwise learned in their professional capacity. Disclosure occurs when protected information becomes accessible to someone who did not previously know it.
The technical transfer of client data to an AI or cloud provider can therefore constitute making that data accessible. It is not automatically unauthorised: Section 203(3) expressly recognises persons who participate in the professional activity. Their access must be limited to what is required for their work.
For lawyers, Section 43e BRAO adds specific duties. The firm must select the provider carefully and conclude a contract in text form that, among other things:
- binds the provider to confidentiality and informs it of criminal consequences,
- limits access to what is required for the service,
- extends safeguards to further service providers, and
- ensures comparable protection where services are provided from abroad.
A DPA and the Section 203 obligations are not the same thing
A data processing agreement under Article 28 GDPR governs personal data. The professional engagement of a service provider must additionally satisfy Section 43e BRAO and Section 203 StGB. One document does not automatically replace the other.
The four decisive requirements
1. Assess the specific product and plan
“Claude” may mean a consumer chat, an enterprise product, an API or a model provided through a cloud platform such as Amazon Bedrock. These options differ substantially in their contracts, retention, administrative controls and data flows. Client data should only be used where the firm can control these points on a binding basis.
Anthropic states that it does not use content from its commercial services to train its models. Published information also describes limited standard retention for the API; arrangements such as zero data retention may be available depending on the product and model. Current terms, exceptions and model-specific requirements need to be checked before use.
2. Engage the provider under Section 43e BRAO
A general confidentiality clause is not necessarily enough. The contract must address the professional-law requirements. This also applies to subprocessors and to everyone who can technically access prompts and outputs. A standard DPA should therefore not be treated as a complete Section 203 solution without further review.
3. Address the GDPR separately
Client matters commonly contain personal data. Relevant requirements include a legal basis, a DPA under Article 28 GDPR, appropriate technical and organisational measures, and transparent retention and access concepts. International transfers must also comply with Articles 44 et seq. GDPR.
A connection to the United States is not automatically unlawful, but it requires an assessment of the transfer mechanism, the actual data flows and any supplementary safeguards. Processing in an EU region often simplifies that assessment, but does not resolve every issue on its own.
4. Design the architecture for confidentiality
Data minimisation should be reflected in the system. Relevant controls include role-based access, encryption, traceable logs, defined retention periods and clear separation between matters. Where the purpose permits, anonymisation or pseudonymisation can further reduce risk.
| Operating model | What law firms should assess |
|---|---|
| Consumer chat | The required contract terms, central administration or binding controls for sensitive client data are often unavailable. |
| Direct commercial access | The DPA, retention, data region, subprocessors and Section 43e obligations must be checked for the specific plan. |
| Claude through Amazon Bedrock in an EU region | AWS documents that model providers cannot access customer prompts and completions in Bedrock. Region, model, logging, IAM and the contractual chain still require assessment. |
| Custom application layer | This can provide central rules, access control, logging and data minimisation, but still depends on a properly configured model and cloud layer. |
EU hosting is one control, not a complete seal of approval
Server location does not answer who can access data, how long content is retained, which logs are created or which subprocessors are involved. These issues must be assessed together.
Practical checklist for using Claude
- Distinguish clearly between consumer and commercial products.
- Document the purpose, data categories and necessary access.
- Conclude a service-provider agreement in text form under Section 43e BRAO.
- Review the Article 28 GDPR DPA and subprocessors.
- Map the data region and possible international transfers.
- Exclude training with client content and define retention.
- Configure roles, encryption, logging and deletion.
- Anonymise or pseudonymise client data where possible.
- Establish internal policies, approvals and training.
- Professionally review AI output before use.
Frequently asked questions
Can German lawyers use Claude with client data?
The use may be permissible. The firm must assess and document the service provider, the specific plan, the data flows and the technical safeguards.
Is a DPA sufficient?
No. The DPA addresses Article 28 GDPR. The requirements of Section 43e BRAO and Section 203 StGB apply in addition.
Is an EU region mandatory?
The law does not impose a blanket EU-server requirement. An EU region can reduce international-transfer risks. The actual access rights, contractual chain and transfers still need to be assessed.
Is zero data retention always available?
No. Availability and exceptions depend on the product, model and provider. The current documentation and individual agreement govern.
Sources and further reading
- Section 203 StGB - Violation of private secrets
- Section 43a BRAO - Basic duties and Section 43e BRAO - Use of services
- General Data Protection Regulation, in particular Articles 28 and 44 et seq.
- Anthropic Commercial Terms and commercial data retention information
- AWS documentation on data protection in Amazon Bedrock
Information current as of 3 August 2026. This article provides general information and does not constitute legal advice. A binding assessment requires a review of the specific product, contracts, data flows and organisation of the law firm.