Conducting a DPIA for API-Driven Data Sharing: A Comprehensive Guide based on CNIL recommendations

In today's interconnected digital landscape, Application Programming Interfaces (APIs) are crucial for seamless data sharing. However, using APIs for data transfer, especially when involving personal data, necessitates a robust Data Protection Impact Assessment (DPIA). This post outlines key factors to consider when conducting a DPIA for API-driven data sharing.

What is an API?

An API is a set of rules and protocols that allow different software applications to communicate and exchange data. It acts as an intermediary, enabling data to flow between systems without direct access to the underlying databases.

Key Actors in API-Driven Data Sharing:

• Data Holder: The organization that owns and controls the data.
• API Manager: The entity responsible for managing the API, including security, access control, and performance. This may be the data holder or a third party.
• Data User: The organization that accesses and uses the data through the API.

Factors to Consider During a DPIA:

1. Data Access and Authorization:

• Type of Access: Is the API providing read-only or write access? Write access significantly increases potential risks.
• Access and Authorization Procedures: How are users authenticated and authorized? Strong authentication mechanisms are essential.
• Level of Security: What security protocols are used for authentication (e.g., OAuth 2.0, API keys)?
• Technical Maturity and Operational Capabilities: Evaluate the technical maturity of all involved organizations. Less mature organizations may introduce vulnerabilities.
• Technical and Organizational Measures: Implement robust measures like encryption, firewalls, and intrusion detection systems.
• Data Categories: Identify the categories of data being shared, particularly sensitive or special categories (e.g., health data, biometric data).
• Data Accuracy and Query Precision: Ensure data accuracy and the ability to restrict access to only necessary information.

2. Controls and Safeguards:

• Access and Action Logging: Implement comprehensive logging to track all API access and actions.
• Transparency to Individuals: Provide clear and detailed information to data subjects about data sharing, including:Data shared.Operations performed (e.g., anonymization, pseudonymization).Frequency and volume of access.Security measures in place.
• Data Minimization: Ensure only necessary data is shared.
• Documentation: Establish clear documentation between the data holder and data user, defining roles, responsibilities, and data formats.
• Sandbox Testing: Use fictitious or synthetic data in a sandbox environment to understand requirements when precise data categories are unknown.
• Consent Withdrawal Mechanisms: Implement technical mechanisms to restrict API access when data subjects withdraw consent.
• Rate Limiting and Blocking: Implement rate limiting and block access after a certain number of failed attempts.
• Write Request Limitations: Limit write requests to strictly necessary actions.
• Dedicated Governance: Establish a governance mechanism for each data reuse and data holder, including technical descriptions.
• Version Management: Implement version control for the API to allow for reverting to previous versions in case of risks.
• Data Provenance Documentation: The data holder should maintain documentation detailing:Data source and collection methods.Update frequency.Transmission format.Historical depth and reliability.Pseudonymization or anonymization processes.
• Write Request Integrity: When handling write requests, ensure procedures are followed to maintain data integrity and monitor server responses for errors.
• Data Separation: Raw data should be physically or logically separated from processed data.
• Automated Data Export: Use secure automated data export processes to feed the API source base, minimizing latency.

3. Data Subject Rights:

• Right to Information: Data subjects have the right to be informed about data sharing activities which makes it necessary for organizations to maintain logs of data shared using APIs.
• Right to access: Data subjects have the right to know what data is being processed.
• Right to rectification: Data subjects have the right to correct inaccurate data.
• Right to erasure: Data subjects have the right to request data deletion.
• Right to restriction of processing: Data subjects have the right to limit the use of their data.

Key Takeaways:

• A thorough DPIA is essential for responsible API-driven data sharing.
• Prioritize security, transparency, and data minimization.
• Establish clear roles and responsibilities between data holders and data users.
• Implement robust technical and organizational measures to protect personal data.
• Always keep the data subject rights at the forefront of the process.