The GDPR imposes several obligations on data controllers when they engage data processors to process personal data on their behalf. One of these obligations is to ensure that the contract or other legal act between the controller and the processor stipulates that the processor must assist the controller in complying with its obligations under the GDPR, including the obligation to notify personal data breaches to the competent supervisory authority and, where applicable, to the affected data subjects1. However, this does not mean that the processor can directly notify the supervisory authority without the involvement of the controller. The GDPR clearly states that it is the controller's responsibility to notify the supervisory authority without undue delay and, where feasible, not later than 72 hours after having become aware of the breach2. The processor must only notify the controller without undue delay after becoming aware of the breach3. Therefore, requiring that the processor directly notify the appropriate supervisory authority is not an action that a data controller can depend upon to avoid liability in the event of a security breach, as it would be contrary to the GDPR and the controller's own obligation. Options A, B and D are actions that a data controller can take to reduce the risk of liability, as they demonstrate that the controller has exercised due diligence, assessed the potential impact of outsourcing, and chosen a reliable and compliant processor. References: 1: Article 28(3)(f) of the GDPR 2: Article 33(1) of the GDPR 3: Article 33(2) of the GDPR