KPN has significant market power on certain segments of the wholesale market in fixed telephony (on dual call services). According to the ACM (Dutch Competition Authority) however, the growth of Vodafone Ziggo has led to a condition of joint dominance. The ACM announced that further assessment will be necessary following some serious doubts expressed by the EU Commission and BEREC about ACM's conclusion that KPN continues to have SMP.  See additionally: https://www.acm.nl/nl/publicaties/publicatie/17066/Intrekking-ontwerpbesluit-marktanalyse-Hoogwaardige-Wholesaletoegang/