Make your website GDPR compliant today — Cookiebot automates cookie consent, scanning, and compliance so you don't have to.
Try Cookiebot Free
Article 34
Communication of a personal data breach to the data subject
Chapter 4|Controller and Processor|📖 5 min read
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.
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).
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.
4. If 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.
Understanding This Article
Article 34 complements Article 33 by requiring notification to affected individuals when breach poses high risk. This empowers individuals to take protective steps.
Paragraph 1 - High Risk Threshold:
Notification required when breach "likely to result in high risk" to rights and freedoms. This is a higher bar than Article 33's "risk" threshold.
High Risk Examples:
Identity theft risk
Financial loss
Discrimination risk
Reputational damage
Physical harm risk
Loss of confidentiality of professional secrets
Significant economic or social disadvantage
Paragraph 2 - Content Requirements:
Communication must:
Be in clear and plain language (accessible to ordinary person)
Describe nature of breach
Include information from Article 33(3)(b), (c), (d):
(b) Contact details of DPO or contact point
(c) Likely consequences
(d) Measures taken/proposed to address and mitigate
Paragraph 3 - Three Exceptions:
(a) Effective encryption: Data rendered unintelligible to unauthorized persons (e.g., strong encryption with secure keys)
(b) Risk mitigated: Subsequent measures eliminated the high risk (e.g., quickly recovered data before misuse)
(c) Disproportionate effort: Individualized notification impractical - must use public communication instead (press release, website notice, etc.)
Paragraph 4 - Supervisory Authority Discretion:
Supervisory authority can require notification if controller hasn't done so, or determine that exceptions apply.
Key Points
Required only when breach likely to result in HIGH risk to rights and freedoms
Must communicate without undue delay in clear and plain language
Three exceptions: effective encryption, risk mitigated, or disproportionate effort (then public communication)
Must include nature, consequences, and measures (same as Article 33)
Supervisory authority can require or waive notification
Higher threshold than Article 33 (high risk vs. any risk)
Practical Application
Risk Assessment - Notify or Not?
High Risk - Must Notify Individuals:
Unencrypted personal data exposed online
Financial data (credit cards, bank details) compromised
Health data breach
Login credentials stolen
Social security numbers exposed
Children's data compromised
Data enabling identity theft
Risk But Not High Risk - Notify Authority Only (Article 33):
Email addresses exposed (minor inconvenience)
Basic contact info (names, phone numbers) of limited sensitivity
Invalid: Encrypted backup stolen but keys on same device = Still high risk, must notify
Risk Mitigated Exception:
Email sent to wrong person but quickly recalled and confirmed deleted unread
Unauthorized access detected immediately, data deleted before viewing
System vulnerability patched before exploitation
Disproportionate Effort Exception:
Breach affects millions of individuals, individual notification impractical
Contact information not available
Solution: Press release, website banner, social media, paid advertising
Individual Notification Template:
Subject: Important Security Notice - Your Personal Information
Dear [Name],
We are writing to inform you of a data security incident that may affect your personal information.
**What Happened:**
On [date], we discovered that [describe incident in plain language].
**What Information Was Involved:**
The following information may have been affected: [list: names, emails, account numbers, etc.]
**What We Are Doing:**
We have taken the following steps:
- [Action 1: e.g., Secured the system]
- [Action 2: e.g., Notified authorities]
- [Action 3: e.g., Engaged cybersecurity firm]
**What You Can Do:**
We recommend you take the following precautions:
- Change your password immediately
- Monitor your accounts for suspicious activity
- Be alert for phishing emails
- [Additional specific actions]
**More Information:**
For questions or concerns, please contact:
[Name]
[Email]
[Phone]
[Hours]
We sincerely apologize for this incident and any concern it may cause.
Sincerely,
[Organization]
Timing:
Article 33 (authority): 72 hours
Article 34 (individuals): "Without undue delay" (no specific deadline, but should be prompt)
Typically notify individuals as soon as practical after assessing risk and confirming details