The action is on behalf of drivers working for three companies which were contracted to deliver parcels for Amazon.
The union claims the drivers were employees, and the companies used a “bogus” self- employment model to wrongly deny them employment rights such as the national minimum wage and holiday pay.
The GMB alleges the drivers were required to attend scheduled shifts that were controlled by Amazon and were treated like employees in terms of their working hours, and therefore should have been treated as employees in terms of their rights too.
Two of the drivers also allege they were dismissed for whistleblowing and that they were sacked after raising concerns about working practices.
The union said it was bringing the claims against Amazon, as well as the delivery companies, on the basis that it was Amazon who determined the way that the drivers should work.
GMB general secretary Tim Roache said: “Guaranteed hours, holiday pay, sick pay, pension contributions are not privileges companies can dish out when they fancy. They are the legal right of all UK workers, and that's what we're asking the courts to rule on."
The case is the latest in a series of legal actions brought against companies in the so-called 'gig economy' relating to workers’ rights. In November 2017 tax-hailing platform Uber lost an Employment Appeal Tribunal hearing in a case brought by two drivers who claimed they were entitled to workers’ rights. Its attempt to appeal directly to the Supreme Court was thrown out.
However a similar case brought against Pimlico Plumbers is due to go to the UK’s highest court after the Court of Appeal upheld a claim brought by plumber Gary Smith. The court said Smith was a ‘worker’, entitled to paid holidays and the right to bring a claim for disability discrimination, although he was not an employee.
In July last year the final report of the Taylor Review into modern employment laws recommended legislative reform to make it clearer whether people in work qualify for full employment rights, should be classed as self-employed, or otherwise fall into a new category of 'dependent contractor'.
‘Dependent contractors’ would receive basic rights including the minimum wage, sick pay and holiday entitlements.