South Korea’s KT has filed a complaint in a Seoul court against rival SK Telecom (SKT) for running “deceptive” ads for its new tri-band LTE-Advanced (LTE-A) service, which it announced at the end of December and said is the first in the world.

KT has asked a court for an injunction to stop SKT from running the ads, which it claims are misleading since the tri-band LTE-A rollout is a pilot launch and not available to regular customers, the Korea Times reported.

SKT said tri-band LTE-A, with a theoretical peak download speed of up to 300Mb/s, is offered in areas where signals from all three frequency bands overlap, but didn’t say how many cities or people were covered. It did say in its original press release that since it already has LTE-A coverage – with 800MHz and 1.8GHz base stations in place – in 84 cities, it can offer tri-band service by adding 2.1GHz base stations. It plans to roll out more than 26,000 2.1GHz base stations in the first quarter.

SKT said it is reviewing the case and is considering counteraction.

KT also has complained that SKT has not yet started selling its first tri-band LTE-A-capable device, Samsung’s Galaxy Note 4 S-LTE. A KT executive told the Times “it is, therefore, absurd for SKT to claim that it has succeeded in commercialising tri-band LTE-A services”.

In contrast, KT said Samsung has provided it with 100 tri-band LTE-A-compatible Galaxy Note 4 smartphones.

SKT’s tri-band LTE-A service aggregates three frequency bands: 20MHz of 1.8GHz spectrum, 10MHz in the 800MHz band and 10MHz in the 2.1GHz band. Last month SKT said the service is four times faster than LTE and 21 times faster than 3G.