# Standards and Regulatory References — Data Subject Breach Communication ## Primary Legislation ### GDPR Article 34 — Communication of a Personal Data Breach to the Data Subject - **Art. 34(1)**: When the personal data breach is likely to result in a high risk to the rights and freedoms of natural persons, the controller shall communicate the personal data breach to the data subject without undue delay. - **Art. 34(2)**: The communication to the data subject referred to in paragraph 1 of this Article shall describe in clear and plain language the nature of the personal data breach and contain at least the information and measures referred to in points (b), (c) and (d) of Article 33(3). - **Art. 34(3)**: The communication to the data subject referred to in paragraph 1 shall not be required if any of the following conditions are met: (a) the controller has implemented appropriate technical and organisational protection measures, and those measures were applied to the personal data affected by the personal data breach, in particular those that render the personal data unintelligible to any person who is not authorised to access it, such as encryption; (b) the controller has taken subsequent measures which ensure that the high risk to the rights and freedoms of data subjects referred to in paragraph 1 is no longer likely to materialise; (c) it would involve disproportionate effort. In such a case, there shall instead be a public communication or similar measure whereby the data subjects are informed in an equally effective manner. - **Art. 34(4)**: Where the controller has not already communicated the personal data breach to the data subject, the supervisory authority, having considered the likelihood of the personal data breach resulting in a high risk, may require it to do so or may decide that any of the conditions referred to in paragraph 3 are met. ### GDPR Article 33(3)(b)(c)(d) — Content Referenced by Art. 34(2) - **(b)**: Name and contact details of the data protection officer or other contact point. - **(c)**: Description of the likely consequences of the personal data breach. - **(d)**: Description of the measures taken or proposed to be taken by the controller to address the breach, including measures to mitigate its possible adverse effects. ### GDPR Recital 86 — Communication to the Data Subject - "The communication to the data subject should be made as soon as reasonably feasible and in close cooperation with the supervisory authority, respecting guidance provided by it or by other relevant authorities such as law-enforcement authorities." - "The need to mitigate an immediate risk of damage would call for prompt communication with data subjects whereas the need to implement appropriate measures against continuing or similar personal data breaches may justify more time for communication." ### GDPR Recital 87 — Timeliness - "It should be ascertained whether all appropriate technological protection and organisational measures have been implemented to establish immediately whether a personal data breach has taken place and to inform promptly the supervisory authority and the data subject." - The notification should be made "without undue delay." ### GDPR Recital 88 — Form and Procedure - "In setting detailed rules concerning the format and procedures applicable to the notification of personal data breaches, due consideration should be given to the circumstances of that breach, including whether or not personal data had been protected by appropriate technical protection measures, effectively limiting the likelihood of identity fraud or other forms of misuse." ## Regulatory Guidance ### EDPB Guidelines 9/2022 — Section 4 on Data Subject Communication - Section 4.1: Distinguishes between "risk" (Art. 33 SA notification threshold) and "high risk" (Art. 34 DS notification threshold). High risk exists when the breach may lead to physical, material, or non-material damage including discrimination, identity theft or fraud, financial loss, or damage to reputation. - Section 4.2: The communication must be in "clear and plain language" — EDPB interprets this as avoiding legal and technical jargon, using short sentences, and being directly comprehensible to the average data subject. - Section 4.3: The communication should be a dedicated, standalone message — not bundled with invoices, newsletters, or general correspondence. - Section 4.4: Art. 34(3)(a) exemption requires encryption that was state-of-the-art at the time of the breach, with confirmation that encryption keys were not compromised. ### ICO Guidance on Communicating Breaches to Individuals (2023) - Notification must be "proactive and direct" — the controller cannot satisfy Art. 34 by merely publishing information and waiting for individuals to find it (unless Art. 34(3)(c) applies). - The ICO expects controllers to use the same communication channel normally used with the data subject (email for digital customers, post for postal customers). - Notifications should include "practical steps the individual can take to protect themselves." ### CNIL Recommendation on Breach Communication to Data Subjects (2022) - CNIL recommends including: a dedicated helpline number, an FAQ page, and information about the right to lodge a complaint with the CNIL. - The communication should arrive within days, not weeks, of the breach determination. ## Enforcement Precedents - **ICO (UK) — Marriott International (October 2020)**: GBP 18.4 million fine. The ICO specifically criticized the delay in communicating the breach to affected individuals and the inadequacy of the initial data subject notification, which did not clearly explain the risks. - **AEPD (Spain) — EasyJet (2021)**: Proceeding related to delayed and inadequate communication to 9 million affected customers following a data breach. The AEPD examined whether the communication met Art. 34(2) content requirements. - **CNIL (France) — Accor SA (2022)**: EUR 600,000 fine. Among the violations, CNIL found that the data subject breach notification was sent bundled with a promotional email, making it difficult for recipients to identify it as a security notification. - **AP (Netherlands) — TikTok (2021)**: EUR 750,000 fine related to privacy information not being available in Dutch. Applied by analogy, breach notifications must be in the language of the data subject. ## ISO/IEC Standards - **ISO/IEC 27701:2019** — Section 7.3.6: Requires the organization to communicate privacy breaches to relevant interested parties (including data subjects when required by applicable legislation) in a timely manner. - **ISO/IEC 27035-3:2020** — Information Security Incident Management Part 3: Guidelines for ICT Incident Response Operations. Section 8.5 covers communication management during incidents, including stakeholder notification.