A sales consultant in Telenor Norge AS with 32 years’ seniority was dismissed because of cost reductions. The selection circle was limited to the business division in Trondheim, consisting of 11 employees. The Supreme Court found, as the l the Court of Appeal, that the limitation of the selection circle did not meet the requirement of due reason to deviate from the principle of seniority, pursuant to section 8-2 of the Basic Agreement between LO and NHO, by which Telenor Norge AS is bound. It was accepted that Telenor Norge AS had due reason for deviating from the principle that the entire company is a selection circle. The number and composition of employees included in the selection group in Trondheim, however, implied that the principle of seniority was substantially weakened. In the assessment of due reason, it should therefore have been considered which or how many employees were included in the selection group. The failure to assess this factor was sufficient for considering the dismissal invalid and thus illegal. Telenor Norge AS’s appeal against the Court of Appeal’s judgment was dismissed.