Article 59 — Processing of personal data in regulatory sandboxes (EU AI Act)

Article 59 of Regulation (EU) 2024/1689 — Processing of personal data in regulatory sandboxes. Official text, practical interpretation, key obligations and compliance implications.

Official Text Summary

Article 59 of Regulation (EU) 2024/1689 establishes the conditions under which personal data lawfully collected for other purposes may be processed within AI regulatory sandboxes. It addresses a fundamental tension inherent in innovation environments: real-world AI development frequently requires access to representative personal data, yet general data protection law restricts re-use of data beyond the original collection purpose.

To resolve this, Article 59 introduces a targeted derogation from the purpose limitation principle in Article 5(1)(b) GDPR, applicable exclusively within the controlled environment of a regulatory sandbox established under Article 57 of the Regulation. The derogation is conditional: processing must be strictly necessary for the development, training, and testing of the AI system in question; the personal data must have been lawfully collected in the first instance; access must be restricted to authorised sandbox participants and competent authority staff; and appropriate technical and organisational safeguards must be in place throughout.

The article further requires that personal data processed under this derogation be deleted or anonymised at the conclusion of the sandbox activity. It imposes a duty of close coordination between the AI Act competent authority and the relevant national data protection supervisory authority, ensuring that neither framework is applied in isolation. Member States are permitted to provide for additional safeguards. Recital 90 of the Regulation contextualises this provision as a proportionate measure to enable trustworthy AI development without creating a general exemption from data protection law.

What This Means in Practice

Article 59 matters most to organisations building or testing AI systems that require datasets containing personal data — for example, healthcare AI trained on patient records, fraud detection models drawing on financial transaction histories, or public safety systems using historical incident data.

Without Article 59, repurposing such data for AI development would require identifying a fresh legal basis or obtaining new consent, often impractical at scale. The sandbox derogation allows a provider accepted into a national AI sandbox to use existing personal data collections under defined conditions, without needing to re-establish a legal basis under Article 6 GDPR for the new processing purpose.

In practice, this means sandbox applicants must address data use explicitly in their sandbox plan submitted to the competent authority. The plan should identify the datasets, the categories of personal data involved, the necessity of using real personal data rather than synthetic alternatives, and the safeguards — including pseudonymisation, access controls, audit logging, and data retention schedules — that will be applied.

Organisations should also expect their national data protection authority to be engaged early. Because Article 59 mandates inter-authority coordination, DPAs may issue guidance, conduct reviews, or request information about sandbox processing. Treating data protection as an afterthought is a compliance risk: sandbox approval does not immunise participants from GDPR enforcement.

Finally, sandbox participants must build deletion or anonymisation workflows before the programme ends. Controllers who retain personal data beyond the sandbox period without an independent legal basis will be in breach of both Article 59 and GDPR Article 5(1)(e).

Key Obligations

• Lawfulness of original collection: Personal data processed in the sandbox must have been collected lawfully under GDPR in the first instance. Article 59 does not legitimise the processing of unlawfully obtained data.
• Necessity assessment: Participants must demonstrate that processing personal data is strictly necessary for the AI development or testing activity; the use of synthetic, anonymised, or aggregated data must be considered and ruled out where practicable.
• Restricted access: Access to personal data within the sandbox must be limited to authorised personnel of the participating organisation and, where applicable, staff of the competent authority conducting oversight. General organisational access is not permitted.
• Technical and organisational safeguards: Appropriate measures — including pseudonymisation, encryption, access controls, and audit trails — must be implemented and documented throughout the duration of sandbox processing.
• Inter-authority cooperation: The AI Act competent authority and the national data protection supervisory authority must coordinate their oversight of sandbox activities. Participants should be prepared to engage with both bodies.
• Data deletion or anonymisation on exit: Upon conclusion of sandbox activities, personal data processed under the Article 59 derogation must be deleted or irreversibly anonymised, unless Union or Member State law requires or permits further retention.

Relationship to Other Articles

Article 59 cannot be read in isolation. It is directly dependent on Article 57, which establishes the obligation for Member States to set up at least one AI regulatory sandbox at national level, and Article 58, which governs the general operation of those sandboxes, including participant selection, duration, and supervisory arrangements.

The personal data derogation in Article 59 interacts with the GDPR framework as a lex specialis provision: it modifies purpose limitation under GDPR Article 5(1)(b) but leaves all other obligations intact, including the legal basis requirements of GDPR Article 6, data subject rights under GDPR Chapter III, and accountability obligations under GDPR Article 5(2). Organisations should also consult Article 10 of the EU AI Act, which imposes specific requirements on data governance and training datasets for high-risk AI systems — many of the data quality principles articulated there inform what constitutes adequate safeguards in the sandbox context. Recital 90 provides important interpretive context on the legislative intent behind the derogation.

Compliance Timeline

Article 59 became part of Union law when the EU AI Act entered into force on 1 August 2024, twenty days after publication in the Official Journal. However, the provisions of Title VI — including Article 59 — apply from 2 August 2025, the date by which Member States were required to have designated their competent authorities and by which the general governance framework, including sandbox obligations, became operational.

This means national regulatory sandboxes should have been established and accepting participants from August 2025 onward. Organisations wishing to invoke the Article 59 derogation must first gain admission to a recognised sandbox under Article 57; there is no standalone right to claim the personal data processing derogation outside that framework.

For reference, the broader AI Act phasing is as follows: prohibitions on unacceptable-risk AI applied from 2 February 2025; GPAI model obligations from 2 August 2025; obligations for high-risk AI systems listed in Annex III apply from 2 August 2026 (with a transitional period to 2 August 2027 for certain systems already on the market). Article 59 is therefore already in force and directly relevant to any organisation currently engaged in, or planning to enter, a national AI regulatory sandbox.