I'm seeing this too. This Ubuntu bug seems to be related: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/21506
T-Mobile International AG Aufsichtsrat/ Supervisory Board: René Obermann (Vorsitzender/ Chairman) Vorstand/ Board of Management: Hamid Akhavan (Vorsitzender/ Chairman), Michael Günther, Lothar A. Harings, Katharina Hollender Handelsregister/Commercial Register Entry: Amtsgericht Bonn, HRB 12276 Steuer-Nr./Tax No.: 205 / 5777/ 0518 USt.-ID./VAT Reg.No.: DE189669124 Sitz der Gesellschaft/ Corporate Headquarters: Bonn