Tertium genus

In Dutch law, the term tertium genus denotes a third category or hybrid form that does not fall squarely within either of the two classical categories, such as public versus private or employment versus self-employment. The expression is invoked where the legislature or the courts introduce a new classification that draws elements from both of the original categories.

The practical significance of a tertium genus lies in the fact that it frequently gives rise to specific statutory regimes, such as distinct tax treatment or separate rules on liability. In practice, such a third category may arise, for example, in public-private partnerships or in certain contractual arrangements governed by administrative law.

Courts resort to the term to prevent a legal relationship from being artificially forced into an existing binary classification, thereby preserving scope for tailored legal solutions.