tarkoitussidonnaisuuteen

Tarkoitussidonnaisuus, or purpose limitation, is a fundamental principle of personal data protection in the European Union, including Finnish data protection law. It requires that personal data be collected for specified, explicit, and legitimate purposes and not further processed in a way that is incompatible with those purposes. The purposes should be communicated to the data subject at the time of collection and kept in a clear, documented form.

Key requirements include specifying the purposes for which data is processed, ensuring that data processing remains within those stated purposes, and limiting the collection and use of data to what is necessary to achieve those purposes. Data controllers must determine and document the purposes before processing, and they should implement measures to prevent processing for unrelated uses. If a new purpose arises, it must be compatible with the original purpose or require a new legal basis and, in some cases, re-consent.

Exceptions exist for compatible further processing, particularly for archiving in the public interest, scientific or historical research, or statistical purposes, provided appropriate safeguards are in place. In such cases, processing may be permitted even if the new purpose differs from the original one, subject to safeguards and impact assessments as required by law.

In Finland, tarkoitussidonnaisuus is implemented through the GDPR framework and national legislation such as the Information Protection Act (Tietosuojalaki). Organizations must document processing purposes, assess feasibility of reuse for new purposes, and inform data subjects about how their data will be used. The principle supports data minimization and accountability in data handling.