I am not sure I really understand the concept of "joint controllers" in GDPR, and I'd like to have some concrete examples, especially examples of joint controllers relating to the internet (websites, services, hosting, providers, etc.), if it makes sense for any to exist.
The website of the European commission has a similar asked question with answer and a small example:
Controller and processor
A brewery has many employees. It signs a contract with a payroll company to pay the wages. The brewery tells the payroll company when the wages should be paid, when an employee leaves or has a pay rise, and provides all other details for the salary slip and payment. The payroll company provides the IT system and stores the employees’ data. The brewery is the data controller and the payroll company is the data processor.
Your company/organisation offers babysitting services via an online platform. At the same time your company/organisation has a contract with another company allowing you to offer value-added services. Those services include the possibility for parents not only to choose the babysitter but also to rent games and DVDs that the babysitter can bring. Both companies are involved in the technical set-up of the website. In that case, the two companies have decided to use the platform for both purposes (babysitting services and DVD/games rental) and will very often share clients’ names. Therefore, the two companies are joint controllers because not only do they agree to offer the possibility of ‘combined services’ but they also design and use a common platform.
If you want more information on the legal part, here some links to the relevant GDPR Articles:
- Legal information on joint Controllers you can find in the GDPR Article 26.
- The definition of a controller in the GDPR Article 4 (7).
- The definition of responsibility of a controller. GDPR Article 24
- The definition of a processor. GDPR Article 28.
- Processing under the authority of the controller or processor. GDPR Article 29