Privacy Policy

This English version is provided for convenience. The German version is legally binding.

1. Controller

The controller within the meaning of Art. 4 (7) GDPR is:

Please send any data protection requests to the email address above. Further details are available in our Legal Notice (Impressum).

2. Overview

BelegBridge currently offers a free web validator for electronic invoices (XRechnung and ZUGFeRD/Factur-X) with an error translator and an invoice visualizer, the corresponding public API endpoints /api/v1/validate and /api/v1/visualize, and a waitlist for the paid bridge that is in preparation. We have designed these services so that as little personal data as possible is processed:

3. Hosting

This website and the validation services are operated on servers of the following hosting provider: Hetzner Online GmbH (Rechenzentrum Standort Nürnberg, Deutschland, ISO/IEC 27001). The servers are located in Germany or elsewhere in the European Union. We have concluded a data processing agreement with the hosting provider under Art. 28 GDPR, which obliges the provider to process data only on our instructions and to implement appropriate technical and organizational measures.

Where the hosting provider processes connection data at network level (for example to deliver data packets or to defend against attacks), it does so within the scope of this agreement. The legal basis is our legitimate interest in the secure and reliable operation of our website (Art. 6 (1) (f) GDPR).

4. Processing of uploaded invoices (memory only)

When you upload an XML or PDF file (up to 15 MB) to the validator, or send it to /api/v1/validate or /api/v1/visualize, the following happens:

1. The file is transmitted with transport encryption (TLS) and held exclusively in the application's working memory.
2. The application detects the format and profile and rejects unsafe XML constructs (for example DOCTYPE and ENTITY declarations).
3. The file is forwarded only to internal validation services running within the same infrastructure – the official KoSIT validator with the XRechnung configuration and Mustang/veraPDF for the PDF/A check. These services have no internet access.
4. The result (validation report, translated notes and, if requested, a readable preview or PDF) is sent back to you.
5. All file contents are then discarded. For a PDF download, the file – which is kept only in your browser – is transmitted again and processed in the same way.

Personal data of third parties: Invoices regularly contain personal data, for example names of contact persons, email addresses, phone numbers, addresses or bank details (IBAN) of the seller and the buyer. This information also applies to persons whose data are contained in uploaded invoices (Art. 14 GDPR). Please only upload files that you are entitled to process.

Legal basis: Art. 6 (1) (b) GDPR, insofar as you use the validator under our terms of use; otherwise, and with regard to personal data of third parties contained in the invoice, Art. 6 (1) (f) GDPR. Our legitimate interest, and that of the uploading user, lies in checking electronic invoices for compliance with the statutory requirements (§ 14 UStG, EN 16931).

Obligation to provide data: Using the validator is voluntary. Without uploading a file, no check can be carried out.

Retention: None. Because invoice contents are not stored, we cannot provide information about, correct or delete them after processing has finished – there is nothing left to do so.

5. Connection data & abuse protection

When you access our website, your browser automatically transmits technical information (IP address, date and time of the request, requested URL, browser type and version). This information is technically required to deliver the website. The application itself does not store or log raw IP addresses.

To protect the free validator and the API against abuse and overload, we limit the number of requests (rate limiting). For this purpose, a hash value is calculated from your IP address and a random salt that is regenerated daily (SHA-256). This hash value and the associated request counter are held exclusively in volatile memory. Because the salt is replaced every day and the old salt is discarded, earlier hash values can no longer be linked to an IP address; all counters are lost at the latest when the application restarts.

Technical application logs are structured and redacted: they contain no IP addresses and no invoice contents, only technical details such as time, requested path, status code and processing time. They are kept only as long as necessary for operation and troubleshooting.

Legal basis: Art. 6 (1) (f) GDPR. Our legitimate interest lies in the secure, stable and fair provision of our services.

6. Early-access waitlist

The paid bridge is in preparation. If you would like to be informed about the launch and early-access conditions, you can join our waitlist. We process:

• your email address (required),
• your company name (optional),
• the plan you are interested in and your billing preference (monthly or annual),
• the time of your consent.

Purpose: To inform you about the launch of the paid bridge, early-access and founding-member conditions, and to plan capacity.

Legal basis: Your consent under Art. 6 (1) (a) GDPR. You can withdraw your consent at any time with effect for the future (Art. 7 (3) GDPR), for example by sending an email to hello@belegbridge.eu. The lawfulness of the processing carried out until the withdrawal remains unaffected. Joining the waitlist is voluntary.

Processing: The data are forwarded to a mailbox or webhook endpoint designated by the operator. Within the application itself, only a one-way hash of your email address together with plan, billing preference and time is kept in volatile memory to detect duplicate sign-ups. If a service provider is used to receive the data, this is done on the basis of a data processing agreement under Art. 28 GDPR.

Retention: We delete your data on request or after withdrawal of your consent, and at the latest when the waitlist ends, but no later than 12 months after your sign-up.

7. No cookies, no tracking

We do not use cookies and do not store or read information on your device for analytics or advertising purposes. We use no analytics or tracking tools and no social media plugins. Fonts, scripts and stylesheets are delivered exclusively from our own server; no content is loaded from third parties (such as CDNs or external font services). Your selected language is transmitted in the URL (parameter lang=en), not in a cookie.

Since we do not store or access information on your device beyond what is strictly necessary for the service you requested (§ 25 (2) no. 2 TDDDG, German Telecommunications Digital Services Data Protection Act), no cookie banner is required.

8. Recipients & transfers to third countries

Recipients of personal data are our hosting provider (as a processor, see section 3) and, for waitlist sign-ups, the mailbox or webhook endpoint designated by the operator (see section 6). Uploaded invoices are not passed on to any third parties.

No personal data are transferred to countries outside the European Union or the European Economic Area in connection with the free tools.

9. Retention periods

• Uploaded invoices: only during processing in volatile memory; no storage.
• Rate-limit hashes: only in volatile memory; unlinkable after the daily salt rotation and lost at the latest on restart.
• Application logs: contain no IP addresses or invoice contents; kept only as long as needed for operation and troubleshooting.
• Waitlist data: until withdrawal of consent, at the latest when the waitlist ends or after 12 months.

Statutory retention obligations remain unaffected.

10. Your rights

Under the GDPR, you have the following rights with regard to your personal data:

• Right of access (Art. 15 GDPR)
• Right to rectification (Art. 16 GDPR)
• Right to erasure (Art. 17 GDPR)
• Right to restriction of processing (Art. 18 GDPR)
• Right to data portability (Art. 20 GDPR)
• Right to withdraw consent at any time with effect for the future (Art. 7 (3) GDPR)

To exercise your rights, simply send an email to hello@belegbridge.eu. We do not use automated decision-making, including profiling, within the meaning of Art. 22 GDPR.

11. Right to lodge a complaint with a supervisory authority

Without prejudice to any other remedy, you have the right to lodge a complaint with a data protection supervisory authority (Art. 77 GDPR), in particular in the member state of your habitual residence, your place of work or the place of the alleged infringement. The supervisory authority responsible for us is: die für den Sitz des Anbieters zuständige Landesbeauftragte bzw. der zuständige Landesbeauftragte für den Datenschutz.

12. Data security

• Transport encryption (TLS) for all connections to our website and API.
• Processing of invoice contents exclusively in volatile memory, without storage on disk or in databases.
• Validation services isolated in an internal network without internet access.
• Upload size limit (15 MB) and rejection of unsafe XML declarations (protection against XXE attacks).
• No external resources (fonts, scripts, CDNs) and a strict Content Security Policy.
• Redacted logs without IP addresses or invoice contents.

13. Planned paid bridge (early access)

The paid bridge (automatic conversion of Stripe, PayPal or email invoices into ZUGFeRD/XRechnung, seller profiles, dispatch to buyers and DATEV, customer accounts) is in preparation and not yet available. When it launches, we will supplement this privacy policy accordingly. For invoice data processed through the bridge, the customer will be the controller and we will act as a processor under a Data Processing Agreement (AVV) under Art. 28 GDPR.

14. Changes to this policy

We update this privacy policy when our services or the legal situation change. The version published on this page applies.

Last updated: November 2026