So there we have it. Last week, an employment tribunal ruled that the job of a shop floor assistant stacking ambient food or picking online orders for customers in store (a role mainly carried out by women), does not compare with the work of the (mainly male) staff working in a distribution centre.

However, colleagues who look after the chilled aisles, work in the bakery department or happen to ‘man’ the checkout are now in for a slice of a potentially historic £1.2bn payout, thanks to the equal pay case taken up by the GMB union and its lawyers. 

The court ruled these female-dominated jobs were comparable with the male-dominated roles in a typical Asda warehouse – but struck out the first two for not meeting its threshold.

Those statements may sound shocking, but are just a small part of the massive ethical and legal issues being decided, as they feature in the latest twist in a legal saga which began in 2014 and which, by all accounts, still has plenty of mileage in the tank yet.

On Friday, an employment tribunal in Manchester ruled that of 14 so-called “lead claimants” representing the various roles in Asda stores, 12 could go through to the final stage of the case, which will decide if there are reasons (beyond gender) that could justify Asda paying them less than their DC counterparts.

The GMB and lawyers Leigh Day are now considering whether to appeal on behalf of the shop floor assistants (edible grocery), who work across the ambient section in Asda and the “personal shoppers”, who – rather than tending to rich housewives, as the name suggests – spend their time picking online orders.

While they were the only two categories not to make it through to the next stage of the case, they represent around 20% of the 60,000 workers represented in the fight. This has huge implications, not just for Asda, but for the supermarket and wider retail sector too.

Sources claim after Friday’s ruling there has been a huge “outpouring of frustration” from those among the 12,000 colleagues who have been struck out.

Meanwhile, both the GMB and Asda had very different interpretations of the latest developments – not for the first time.

“Despite the rulings over those two job roles, which we are now deciding about whether to appeal, there is no doubt that this is a massive victory and we have now proved that tens of thousands of retail roles are being paid less than they would be in comparable roles in a depot,” Nadine Houghton, GMB national officer, tells The Grocer.

“It resoundingly demonstrates a pay structure of discrimination against lower-paid workers, who are mostly women.

“We will now be urging Asda to do what they should have done long ago and come up with a financial settlement for these workers rather than keep dragging out this case.”

UK retail is watching

Yet Asda continues to “strongly reject” claims that it pays staff different rates based on their sex.

It also points out that rather than a clear victory for the union, as billed, the tribunal’s ruling was that even for the cases of the 12 job types who made it through to the final stage, there was a “mixed picture” over the comparability of roles with those working in the warehouse.

Of those 12, in fact, only the role of section leader was found to have been of equal value to all the comparators looked at.

It doesn’t exactly smack of ”we’re all in this together”, but such are the thorny issues that have come to the surface in a case which has become known as the Made in Dagenham of the supermarket world.

Asda’s case may be the first and the most advanced through the process of all the UK supermarkets, but its not just its pockets that are at stake.

With Leigh Day having ongoing court action in similar claims against Morrisons, Tesco and Sainsbury’s, as well as other retailers including Next, the retail world is watching these developments with bated breath.

As, no doubt, will be the thousands of pickers and ambient shelf stackers, who have just been told that their jobs are not as hard as those of their colleagues in the next aisle.