Question juridique clé
Whether the employer could invalidate the social plan severance clause for fundamental mistake or deceit.
Solution extraite
No. The alleged concealment of a filed declaratory action did not justify rescinding the normative social plan clause vis-à-vis the employee.
Motifs extraits
The employer could not show a relevant causal mistake affecting the employee's entitlement. Any dispute about the consultation period concerned the employer's relationship with the negotiation group, not the normative rights of employees. The employer could have reserved the issue expressly, but did not.