Behind the Nike, Lacoste & Superdry Greenwashing Controversy

Three major fashion brands have been publicly rebuked by Britain's advertising watchdog for making unsubstantiated claims about the sustainability of their products.

The UK’s Advertising Standards Authority has banned paid-for Google advertisements from Nike, Lacoste and Superdry after ruling that all three companies failed to provide the necessary evidence to back up the environmental claims their ads made. 

The rulings represent the latest salvo in a broader regulatory crackdown on greenwashing within the fashion industry, which the UN suggests contributes to between 8% and 10% of global emissions.

What was the problem with Nike, Superdry and Lacoste’s adverts?

Nike's Google ad for tennis polo shirts promoted "sustainable materials" but the company could not adequately justify the claim upon request.

The sportswear giant argued that the promotion was "framed in general terms" and suggested consumers would understand it referred only to selected products on its website that incorporated recycled materials.

The ASA rejected this defence, ruling that Nike had failed to include qualifying details or explain the basis of its sustainability assertions.

Elsewhere, Superdry's advert urged shoppers to "unlock a wardrobe that combines style and sustainability".

The British retailer contended that customers would interpret this to mean its clothes were either stylish, sustainable or both – not that all products met high environmental standards.

The watchdog found that these claims were "ambiguous and unclear", though, and would lead consumers to believe all Superdry products were sustainable.

Lastly, Lacoste promoted its children's range as "sustainable clothing" and told the ASA it had spent years reducing the carbon footprint of its products, but the watchdog argued that the French designer could not prove that this range had “no detrimental effect on the environment”.

Lacoste acknowledged to regulators that terms such as "sustainable" and "eco-friendly" were "very difficult to substantiate".

How regulatory standards are enforced in advertising

The ASA's rulings hinge on the UK advertising code, which states that environmental claims must be clear and "supported by a high level of substantiation".

In each case, the watchdog determined that the retailers' use of the term "sustainable" lacked sufficient context, which insinuated that the claims were absolute rather than qualified.

"The claim was absolute and therefore a high level of substantiation in support needed to be produced," the regulator stated.

"We had not seen evidence to support it. We therefore concluded the ad was likely to mislead."

All three advertisements were banned, with the companies warned that future promotions must contain qualifying details and robust evidence for any assertions about their products’ environmental performance.

How the ASA is using AI to identify greenwashing

The offending ads were identified through the ASA's monitoring system, which uses AI to track the legitimacy of claims in the advertising of fashion retailers.

"These rulings send a clear message that advertisers must be able to back up their green claims with solid evidence, so people get fair, accurate information when they're choosing what to buy,” explains Justine Grimley, Operations Manager at the watchdog.

This could mark a new era in the crackdown on greenwashing where tech is used to enforce regulations more regularly.

On the other hand, AI is also being used by advertisers and ad departments more and more. The worry is that AI still makes too many mistakes to be trusted to deliver compliant and accurate adverts.

For Brinsley Dresden, Co-Head of Advertising and Marketing Law at Lewis Silkin, AI-generated advertisements were creating a "big challenge" for advertisers making tightly regulated green claims.

The fashion sector’s problem with greenwashing

The fashion industry is under more scrutiny than ever in 2025, with fast fashion retailers increasingly feeling the heat from consumers and regulators alike.

According to the Ellen Macarthur Foundation, one truckload of clothing is incinerated or landfilled every second.

And while buying second-hand clothing is becoming more popular, the World Bank suggests that global clothes sales will increase by 65% by 2030.

As a result, many people are demanding greater transparency about how clothes are produced and the kinds of materials they are made from.

Last year, the UK's Competition and Markets Authority reprimanded fast-fashion retailers Asos and Boohoo, along with Asda's George clothing line, over unsubstantiated environmental claims.

Fast fashion giant SHEIN has also been fined in Europe and investigated in the UK for its communications related to sustainability.

The CMA's guidance for the fashion industry states that broad claims such as "sustainable" are likely to mislead consumers, who would reasonably assume products have no negative environmental impact.

Lacoste told the Financial Times it had reduced the environmental footprint of raw materials in its children's collection by 19% since 2022.

Elsewhere, Nike said it remained “committed to providing consumers with clear information to help them make the choices that are right for them.”

Superdry did not respond to requests for comment.