Uber and its drivers will head to court today to battle it out in a legal case over workers' rights.
The hearing at an employment tribunal is due to begin in London and is expected to rule on the status of some Uber drivers in the first case of its kind in the UK.
The action has been brought by the GMB union which represents drivers and law firm Leigh Day.
Uber considers drivers self-employed "partners", however, GMB claims they should be considered employees and have rights as workers, such as minimum wage, mandatory breaks and paid leave.
"Uber is a multinational, multi-billion dollar company and GMB believes they are unlawfully denying their drivers fundamental rights which are designed to ensure workers can enjoy a minimum standard of living," said GMB national secretary Justin Bowden.
Leigh Day employment lawyer Annie Powell said: "On behalf of our clients we will claim that Uber is wrongly classifying its drivers as self-employed with the result that drivers are denied the rights and protections that Parliament intended them to have."
The claim is the first of several to reach the tribunal stage and could pave the way for further cases to move forward. It could also impact thousands of Uber drivers across the UK in terms of their working status, compensation payouts and further claims.
"This claim is vital for the thousands of Uber drivers who work in England and Wales and has implications even wider than that," said Powell.
There are 30,000 Uber drivers in London alone.
Uber has faced similar claims over workers' rights in the US and earlier this year agreed to pay up to $100m to settle a lawsuit over how drivers are classified. They will still be considered as independent contractors, but will make concessions to drivers such as letting them solicit for tips, not deactivating driver accounts "at will" and helping form a drivers association to represent views, subject to a judge's approval.
Uber has argued that drivers enjoy the flexibility and being their own boss.
“More than 30,000 people in London drive with our app and this case only involves a very small number," said Uber's UK regional director Jo Bertram.
"The main reason people choose to partner with Uber is so they can become their own boss, pick their own hours and work completely flexibly. Many partner-drivers have left other lines of work and chosen to partner with Uber for this very reason. In fact two thirds of new partner-drivers joining the Uber platform have been referred by another partner."