Long-term deployment of temporary workers: Supreme Court raises the bar

At the end of 2025, the Supreme Court ruled on the question whether long-term deployment of a temporary worker constitutes abuse of the temporary employment arrangement (ECLI:NL:HR:2025:1733). In this case, better known as the Upfield case, a temporary worker worked for over socithirteen years at the same hiring company through various temporary employment agencies. After the factory closed, he was excluded from the redundancy plan and claimed that he actually had an employment contract with the hiring company. In this judgment, the Supreme Court provides important guidance for employers who make structural use of temporary workers.

In this case, a temporary worker was employed by Unilever from 2009 to 2021 through various temporary employment agencies. After the sale of the ‘margarine’ business to Upfield, production was scaled down and a redundancy plan was drawn up. That redundancy plan applied only to employees with an employment contract with Unilever itself and not to temporary workers. As a result, the temporary worker was excluded from the redundancy plan and claimed that he actually had an employment contract with the hiring company. In his opinion, the temporary employment contract had been abused due to the long-term deployment and the collective labour agreement and redundancy plan should also apply to him.

The key question in these proceedings, which have been pending before the court and the court of appeal since 2022, was whether the assignment was so long-term that the temporary nature of temporary agency work had disappeared. Both the court and the court of appeal previously ruled that there was no abuse and dismissed the claims. The temporary worker then appealed to the Supreme Court.

The Supreme Court stated that, on the basis of Article 5 of the European Temporary Agency Work Directive, Member States are obliged to take measures to prevent the abuse of successive temporary agency work contracts. According to the Supreme Court, abuse of the temporary agency work must be assumed if the duration of the assignment exceeds what, in view of all the circumstances of the case, can reasonably be regarded as 'temporary' and if there is no objective justification for that actual duration.

Although the deployment of a temporary worker for thirteen years is undeniably a strong indication of possible abuse, the Supreme Court emphasizes that long-term deployment is not automatically unlawful. The decisive factor is whether the hiring company can provide an adequate objective explanation for the structural deployment of the same temporary worker so that this does not conflict with Article 5 of the European Temporary Agency Work Directive.