Group Article 29 (A29WP), Notice 1/2010 on the concepts “controller” and “processor,” February 2010, p. 21. . 3. Notwithstanding the provisions of the agreement under paragraph 1, the person concerned may exercise the rights conferred on him by this regulation for and against each of those responsible for the treatment. Section 26 imposes regulations on common processing managers that clearly assign the roles of each person responsible for processing. The principle of transparency requires that all information intended for the public or the person concerned be concise, easily accessible and easily comprehensible, and that clear and clear language be used and, if necessary, visualization. This information could be provided electronically, for example. B when addressed to the public, via a website. This is particularly important in situations where the dissemination of actors and the technological complexity of the practice make it more difficult for the person concerned to know whether, by whom and for what purposes, personal data concerning him are collected, as in the case of online advertising.
Since children deserve special protection, any information and communication in which treatment is directed to a child should be done in language clear and clear enough to allow the child to easily understand them. . The common definition of purposes and means of treatment does not necessarily mean that two people responsible for treatment must have the same purpose. Common control may exist in situations where the purposes pursued are closely linked or complementary, but not identical. This can happen in cases where there is a mutual benefit resulting from the same treatment as an economic benefit, as was the case with Fashion ID. Similarly, the processing of personal data by processing personal data through the statistics of a visitor fan page has allowed Facebook to improve its advertising system and the fan page administrator to obtain statistics on its advertising activities.  In this case, each entity was pursuing its own interests, but both parties were involved in determining the purposes of processing the personal data of the visitors to the fan page that were related.  Article 27. Representatives of processing managers or subcontractors who are not established in UNION 1.
When two or more treatment managers jointly determine the purposes and means of treatment, they are jointly responsible for the treatment. They transparently define their respective responsibilities for the performance of the obligations arising from this Regulation, in particular with regard to the exercise of the rights of the person concerned and their respective obligations, to disclose the information covered by Articles 13 and 14 by agreement with each other, unless the respective responsibilities are determined by EU law or the Member States responsible for processing. The agreement may designate a point of contact for those affected. However, a simple mutual benefit to treatment alone is not sufficient to establish joint control.