The UK Supreme Court has delivered a significant judgment for the food and beverage industry, dismissing Oatly’s appeal and ruling that its trademark “Post Milk Generation” is invalid for use on oat-based food and drink products in the UK.

In a unanimous decision in Dairy UK Ltd v Oatly AB, the Court held that the slogan unlawfully uses the protected term "milk" under UK-assimilated EU agricultural marketing law, even though it appears as part of a broader phrase rather than a product name.

At the heart of the case was whether the word “milk” in “Post Milk Generation” constitutes a prohibited “designation” under Regulation (EU) No. 1308/2013 (retained in UK law post-Brexit), which reserves dairy terms exclusively for animal-derived products.

The Supreme Court found that “milk” is being used as a designation, not merely as a cultural or generational reference and that the phrase does not clearly describe a characteristic quality of the product (such as being milk-free) in a sufficiently direct way to fall within the regulation’s exception.

As a result, the trademark cannot be used on oat-based food and drink products, although it remains valid for non-food items such as merchandise.

Richard May, partner at law form Osborne Clarke, said: “The key principle is straightforward: if a product is not derived from animal milk, it cannot be marketed using reserved dairy designations such as ‘milk’ or ‘cheese’."

He continued: "In practical terms, terminology such as ‘oat milk’ or ‘plant-based cheese’ now carries heightened legal risk in the UK market. Marketing teams will need to ensure that product names and campaign messaging do not stray into protected territory.”

Oatly strongly criticised the ruling.

Bryan Carroll, general manager for Oatly UK & Ireland, stated: “We are deeply disappointed by today’s UK Supreme Court ruling. In our view, prohibiting the trademarking of the slogan ‘Post Milk Generation’ for use on our products in the UK is a way to stifle competition and is not in the interests of the British public. This decision creates unnecessary confusion and an uneven playing field for plant-based products that solely benefits Big Dairy.”

Despite the outcome, Oatly signalled it will continue to use the slogan on merchandise and remain committed to its sustainability-driven brand positioning.

For the wider food and beverage sector, the ruling reinforces that branding, not just labelling, falls within regulatory scope. Even marketing slogans and trademarks can trigger legal restrictions if they reference protected product categories.