FIRST Hampshire is part of the legal challenge. Managing director Richard Soper said: "All we are asking for is confirmation that we are being dealt with under the terms of the legislation. The authorities have devised a formula that is effectively capped, but we can't turn people away once the scheme is in place.

We're strongly of the view that the scheme goes against the legislative requirements that operators are no better, nor any worse off."

Stagecoach South is also part of the legal challenge. Director Edward Hodgson said: "We just want a fair deal. There are some increased costs and having concessionary travellers on buses limits our ability to attract fare-paying customers. People are travelling by bus in far greater numbers and we want to make sure that the scheme reflects that."

Solent Blue Line is not part of the legal challenge. Operations manager Alex Hornby said: "We're not disgruntled to the point that we're appealing. I can't see us appealing for compensation because our point of view is that the whole landscape will change in 2008 (when free nationwide travel is introduced), so what's the point? Our revenue profile is obviously worse off, but it's short-term. We can cope with it and take lessons on board for next time."

No one from Wilts & Dorset was available for comment. It is unclear whether the company is part of the legal challenge.