Overview
- The Landgericht Köln, which issued its judgment on 17 September 2026, prohibited Telekom from replacing the usual network identifier on customers' phone displays with the slogan 'Im besten Netz'.
- The change began as a January 2026 marketing move that showed the slogan on lock screens and in control centers and could not be switched off by affected users.
- The Verbraucherzentrale Bundesverband sued, arguing the display forced advertising on consumers, and the court found the practice to be an 'unzumutbare Belästigung' under Germany's unfair-competition law (UWG).
- Telekom appealed the district court decision to the Oberlandesgericht Köln on 19 October 2026 and the dispute remains pending while the OLG Düsseldorf earlier this month confirmed an interim injunction that 1&1 had won against the campaign.
- The judgment warns that allowing carrier control of system-level identifiers would enable unavoidable advertising, so the appeal will shape whether mobile network labels can be used as mandatory ad space and how easily users can opt out.