An employment law case on whether a plumber was a worker or a contractor will be considered by the UK's highest court today.
Pimlico Plumbers said the Supreme Court hearing will have "significant ramifications" on employment law for a number of industries.
Gary Smith, a plumber who worked for Pimlico Plumbers for five years from 2005, has already won a number of court rulings that determined he could claim "worker" status even though he was described in his contract as a "self-employed operative".
The Court of Appeal said Mr Smith was a worker because he was required to use the firm's van for assignments and was contractually obliged to do a minimum number of hours a week.
The company's chief executive Charlie Mullins said it was different from other cases in the so-called gig economy involving the status of employees including delivery and taxi drivers.
Pimlico Plumbers is appealing against the decision in a hearing likely to last two days, with judgment expected in a few weeks.