3 UK’s appeal against the structure of a planned spectrum auction in the country was rejected, paving the way for regulator Ofcom to conduct the process later this year.

The planned auction, which will see the sale of 4G-ready spectrum and airwaves earmarked for 5G, was originally due to be held in 2017, but was delayed by litigation by both 3 and UK market leader EE, which seperately challenged the regulator’s plans to impose a cap on the amount of spectrum an individual operator can hold. The case was taken to the UK’s High Court, which decided in favour of the rules set by Ofcom.

While EE decided to let the decision lie, 3 appealed the ruling.

The UK’s Court of Appeal has now ended 3’s challenge altogether: bidding is now expected to start in April and operators could be using the spectrum later this year. While Ofcom already received expressions of interest from telecoms companies, it previously said it would not accept formal approaches to participate in the auction until 3’s litigation was resolved.

A 3 representative said it was “disappointed by the court decision but our decision to appeal was the right one.”

3 had argued the cap proposed by Ofcom did not go far enough in addressing competition concerns, while EE claimed there shouldn’t be a cap at all.

Ongoing litigation from 3 and EE drew criticism from Ofcom and rival operators O2 UK and Vodafone UK, which said the legal challenges were delaying the country’s 5G roll-out.

3’s representative added its appeal had “not caused any delay of 5G services to UK consumers, which are not expected to roll out until 2019/20”.

Ofcom and rival O2 UK welcomed the Court of Appeal ruling.