Despite major delays in the rollout, 1&1 can continue to call its mobile network the most modern in Europe.

On Tuesday, the Koblenz Higher Regional Court dismissed an application by Deutsche Telekom with legally binding effect. However, the judges ruled in favor of the Bonn-based company on another point: 1&1 may not advertise its 5G product for the home in its current form.

The mobile operator's share price rose after the ruling was announced and was up 4.4 percent at times. The shares of parent company United Internet rose slightly. Telekom was initially unavailable for comment.

The United Internet subsidiary relies on so-called Open RAN technology to build its mobile network. This makes it possible to combine software and hardware from different providers. Until now, telecommunications groups have mostly relied on products where both come from one supplier. "We have shown that Open RAN technology is fully functional with the launch of our first service," said 1&1 CEO Ralph Dommermuth, who also heads United Internet.

1&1 has so far only erected a small number of the required mobile masts. The company blames its partner and radio tower operator Vantage Towers - a Vodafone holding - for the delays. The Federal Cartel Office is investigating possible obstruction by the 1&1 rival.

(Report by Hakan Ersen, edited by Hans Seidenstücker. If you have any queries, please contact our editorial team at berlin.newsroom@thomsonreuters.com (for politics and the economy) or frankfurt.newsroom@thomsonreuters.com (for companies and markets).)