Last updated: May 2026
1. Controller
The controller responsible for data processing on this website is:
Kerstner GmbH
Werner-von-Siemens-Straße 9
68649 Groß-Rohrheim
Germany
Telephone: +49 6245 90770-0
Email: info@kerstner.de
2. General information on data processing
We process personal data in accordance with the General Data Protection Regulation (GDPR) and applicable German data protection law. Personal data means any information that can identify you personally.
Processing takes place in particular to provide the website, answer enquiries, prepare quotations, handle service cases and meet legal obligations.
3. Hosting and technical provision
Technically necessary data is processed when you access our website. This may include IP address, access date and time, pages visited, browser type, operating system and comparable technical information.
This processing is necessary to provide a secure, stable website. The legal basis is Article 6(1)(f) GDPR. Our legitimate interest is the secure, error-free operation of the website.
4. Contact
If you contact us by form, email or telephone, we process your details to handle your request. These may include name, company, contact details, vehicle and project information, service information, uploaded files and the content of your message.
Depending on the request, processing is based on Article 6(1)(b) GDPR for pre-contractual or contractual enquiries, and otherwise on Article 6(1)(f) GDPR. Our legitimate interest is the efficient handling and documentation of enquiries.
5. CRM and form system
If you contact us through a form, by email or telephone, we process your details to answer your enquiry, prepare quotations, handle service cases and document communications traceably.
In particular, we may process name, company, contact details, request, vehicle and project information, uploaded files and technical transmission data.
We use an external CRM and form system to handle enquiries systematically. The provider is HubSpot Germany GmbH or a company in the HubSpot group. HubSpot processes data on our behalf under a data processing agreement. Where data is processed outside the EU or the European Economic Area, appropriate safeguards apply, in particular the EU Standard Contractual Clauses.
Depending on the request, processing is based on Article 6(1)(b) GDPR for pre-contractual or contractual enquiries, and otherwise on Article 6(1)(f) GDPR. Our legitimate interest is the efficient handling and documentation of enquiries.
Newsletter, marketing automation, analytics, tracking, chat and similar convenience features are used only with valid consent.
6. Cookies and similar technologies
This website may use technically necessary cookies or similar technologies to provide basic functions reliably. Any additional analytics, marketing or convenience functions are used only with your consent.
The legal basis for technically necessary operations is Article 6(1)(f) GDPR. For operations requiring consent, the legal basis is Article 6(1)(a) GDPR.
7. Embedded external content
Where external content, maps, videos, fonts, analytics tools or similar services are embedded on individual pages, technical data may be transferred to the respective provider. Services requiring consent are loaded only after you consent.
8. Retention period
We retain personal data only as long as necessary for the stated purposes or to meet statutory retention duties. Data is then deleted or blocked unless another legal basis for processing exists.
9. Data recipients
Within our company, only departments that need personal data to handle the relevant case receive access. Service providers may also be involved, for example for hosting, IT operations, form and CRM processing or technical maintenance.
We enter into appropriate data processing agreements with service providers who process personal data on our behalf.
10. Your rights
Subject to the applicable legal conditions, you have the following rights:
- access to the personal data stored about you,
- rectification of inaccurate data,
- erasure of personal data,
- restriction of processing,
- data portability,
- objection to certain processing,
- withdrawal of consent with effect for the future.
You may contact us at any time to exercise your rights.
11. Right to lodge a complaint
You have the right to lodge a complaint with a data protection supervisory authority if you believe that processing of your personal data infringes data protection law.
12. Updates to this privacy policy
We update this privacy policy when legal requirements, technical processes or services used change.