Supermarket giant Asda is facing legal action by more than 19,000 people over equal pay at the chain, it is claimed.
Employment law experts at Leigh Day said it was taking legal action against the Leeds-based firm.
Lawyers said it was representing hundreds of former and current employees, mainly female, who feel they have been paid less than others despite carrying out roles of equal value, and had so far been approached by 19,000 staff.
Discrimination and employment law expert Michael Newman said the claims are possible after investigations revealed that employees in the Asda-owned distribution centres were paid more than staff working in the supermarkets themselves.
If the case against Asda, which has 175,000 employees, is successful, claimants may be entitled to six years’ worth of back pay to compensate for the difference in earnings.
The outcome could have implications for other major retailers. Supermarket chains that also own their distribution centres include Sainsbury’s and Bradford-based Morrisons.
New regulations mean employment tribunals have the power to order employers to conduct audits when they are found to be in breach of the equal pay provisions of the Equality Act 2010.
Mr Newman claimed the implications were “enormous for Asda and many other supermarkets in the UK”.
He said: “In the supermarkets, the check-out staff and shelf-stackers are mostly women. The people in the warehouses are pretty much all men. And, as a whole, the group that is mostly men gets paid more.
“Our investigations suggest that the jobs are pretty much the same, in that warehouse staff are responsible for taking items off shelves, putting them on pallets and loading them into lorries.
“In the supermarket, they do the reverse – taking the pallets off the lorries, unstacking them and putting the items on the shelves. Where the jobs are not similar, we still think they are of equal value. Although there have been huge advancements in equal pay within the public sector, there is still a long way to go in the private sector.”
Asda said: “A firm of no-win, no-fee lawyers is hoping to challenge our award-winning reputation as an equal opportunities employer. We do not discriminate and are very proud of our record in this area which, if it comes to it, we will robustly defend.”