There is a fair chance that the seedless mandarins in your local supermarket recently featured in a case at the English High Court. The judgment – the first of its kind in England and Wales – has shone a rare spotlight on an intellectual property (IP) right that most people have never heard of.

This is a good moment to ask the obvious question: what exactly are plant breeders' rights, and why do they exist?

A brief history: where do these rights come from?

Plant breeders' rights (PBR), also known as plant variety rights, are a relatively modern addition to the IP landscape. Unlike patents, trade marks or copyright, which have centuries of legal history behind them, PBRs only emerged as a formal legal concept in the UK in 1964.

The catalyst was a straightforward practical problem. Developing a new plant variety – whether a disease-resistant wheat, a sweeter strawberry or a seedless mandarin – takes years of work, significant investment, and a great deal of scientific skill. Yet once a new variety exists, it can simply be propagated by anyone taking a cutting or saving a seed. Without some form of protection, there is no real benefit to those who did the hard 'graft', and the incentive to invest in new varieties collapses. Such an outcome poses serious risks to agriculture, horticulture, and, by extension, to the food security of the entire population.

One of the proposed international solutions was codified by the Convention of the International Union for the Protection of New Varieties of Plants (UPOV Convention), established in 1961 and in force since 1968, with significant revisions in 1978 and again in 1991. UPOV's purpose is to "provide and promote an effective system of plant variety protection, with the aim of encouraging the development of new varieties of plants for the benefit of society."

In the UK, the domestic implementation of the UPOV Convention is the Plant Varieties Act 1997 (the Act), which provides the UK's national system of plant variety protection (the Act replaced Part I of the older Plant Varieties and Seeds Act 1964, consolidating and updating the UK regime to bring it in line with the modern UPOV framework).

What do Plant Breeders' Rights protect?

Rights known as PBRs are granted under the Act and may subsist in varieties of all plant genera and species. To obtain protection, a variety must be a "qualifying variety" – which means it must be distinct, uniform, stable, and new.

These requirements reflect something important about how plant breeding works. New plant varieties do not emerge out of the blue – they are always derived from earlier, existing varieties[1]. Plant breeding involves discovering or introducing genetic variation and then selecting desirable traits, often aided by modern technologies. Every "new" variety is derived from at least one earlier variety to a greater or lesser degree. The distinctness and novelty requirements exist in the Act to ensure PBRs are reserved for genuine advances, not trivial tinkering.

What can the rights holder actually stop?

For propagating material of a protected variety – the seeds, cuttings, budwood or other material used to grow new plants – the rights holder can prevent a range of commercial acts carried out without authority. This includes the production or reproduction of the variety, offering it for sale, selling it, importing or exporting it, and stocking it for any of those purposes (consistent with most IP rights).

The focus on propagating material is deliberate. The Act is primarily designed to give breeders control at the point where their investment is most at risk: when someone else reproduces and commercialises the variety without permission.

However, the right extends further. It can also cover harvested material – the fruit, flowers or crop itself – obtained through the unauthorised use of propagating material provided that the rights holder did not have a "reasonable opportunity" to exercise their rights in relation to that unauthorised use before the harvested material was obtained.

This "cascade" from propagating material to harvested material is an important feature of the system – but, as discussed below, has been the subject of recent litigation.

The "essentially derived variety" problem

One of the subtler challenges in plant variety protection stems from the very nature of plant breeding. Because new varieties are always developed from earlier ones, there is a risk that newer technologies could enable close copying of successful protected varieties, a form of plagiarism through minor variation, undermining the incentive for original breeding investment.

The UPOV Convention addressed this through the "essentially derived variety" (EDV) concept, which is implemented by the Act. The rights of a PBR holder can extend to varieties that are "essentially derived" from the protected variety. This is where those varieties are predominantly derived from the initial variety, retaining the expression of its essential characteristics while being clearly distinguishable from it, and conforming to it in the expression of those essential characteristics except for differences resulting from the act of derivation.

That last element – what counts as an "essential characteristic," and whether it is truly "retained" – remains one of the more challenging questions in this area of law.

Obtaining and maintaining protection

PBRs are obtained by application to the Controller of Plant Variety Rights. The applicant must be the person who bred or discovered and developed the variety – or their successor in title. As discussed above, the variety must be distinct, uniform, stable and new.

Once granted, protection lasts 25 years for most varieties, and 30 years for trees, vines and potatoes. These periods may be extended by regulation – up to 35 years in the first category and 30 years in the second – where the characteristics of a particular species or group justify it. Throughout the term, the holder must remain able to produce propagating material capable of reproducing the variety.

Disputes over Plant Breeders' Rights

PBRs are genuinely niche. To date, disputes over PBRs very rarely end up in court, they are not well known outside specialist agricultural and horticultural circles, and most IP practitioners will never encounter them. As the English High Court noted in 2026, the EDV concept and the harvested material limitation had been judicially interpreted only a handful of times worldwide, and has never previously been the subject of an English judgment.

So why does it matter when these disputes do arise? Because legal uncertainty has real commercial consequences. Breeders need to know which varieties they can effectively protect and against what kinds of derivative work. Growers, importers and retailers need to understand the limits of their exposure – particularly where varieties are developed and protected across multiple jurisdictions. Unanswered legal questions create risk, and risk shapes behaviour: licensing terms, investment decisions, and market entry strategies all depend on clarity. When courts do address these questions, their answers carry weight well beyond the immediate dispute.

The rarity of litigation also reflects the nature of the industry. Supply chains are specialised, disputes often stay out of court, and the technical complexity of PBR cases makes litigation demanding and expensive. Therefore, when a case does reach the court, it tends to address questions that have never been answered before.

What issues have come up in practice? The Mandarin case in the UK

The High Court's judgment in Nador Cott Protection SAS v Asda Stores Limited [2026] EWHC 553 (Pat) is a useful illustration of exactly the kinds of questions the regime can throw up.

Nador Cott Protection SAS (NCP), the owner of UK Plant Breeders' Right No. 28016 in Nador Cott – a premium mandarin orange – brought infringement proceedings against Asda in respect of Tang Gold (also known as Tango). This is a variety that was developed by irradiating budwood derived from the Nador Cott variety to induce mutations that render the resulting plants sterile, and their fruit seedless.

The case raised two issues for the first time under English law.

First, was Tang Gold an essentially derived variety? The judge, Mellor J, held that the requirement in section 7(3) of the Act – that the derived variety must be predominantly derived from the initial variety while retaining the expression of its essential characteristics – means what it says. The word "retaining" is unqualified and is not satisfied if the essential characteristics of the initial variety have simply been removed. On the facts, "seediness"[2] and pollen viability were essential characteristics of Nador Cott that were not retained in Tang Gold. The claim therefore failed at the first hurdle. The judge noted that this demonstrates just how narrow the EDV concept is under English law, and that a different result might arise under the differently worded EU regulation. This could be a point of real practical significance for businesses operating across both markets.

Second, how should the "reasonable opportunity" condition in section 6(3) of the Act be interpreted? Mellor J held, interpreting section 6(3) of the Act, that "his rights" means the rights conferred by the Act – not a global bundle of rights held in other jurisdictions. He further held that "unauthorised use" can only arise in a territory where the rights holder actually holds a PBR and has not given authority for the relevant use. The "reasonable opportunity" test itself is a flexible, fact-sensitive standard – not a rigid cascade rule requiring rights holders to pursue growers before they can pursue retailers.

Both findings are the first of their kind in England and Wales and notably, NCP is appealing the judgment. If the case proceeds through the Court of Appeal, it is likely to receive close scrutiny both in the UK and beyond.

Key takeaways

PBRs are a quiet but important piece of the IP landscape. They exist because the economics of plant breeding require them and they are carefully drafted to balance protection with freedom to innovate. While there has been little litigation in this area to date, the questions that have arisen – about what makes a characteristic "essential," about the territorial limits of enforcement, and about what counts as a "reasonable" opportunity – are not straightforward. The Nador Cott v Asda judgment is a rare opportunity for those questions to be addressed by the English High Court, and the answers provided are likely to shape how breeders, growers, importers and retailers navigate their legal positions for years to come.

[1] While new varieties do not arise spontaneously, it is possible that some may originate from naturally occurring plants that have not yet been identified or documented in the wild. In this sense, "derived" refers to their biological origin rather than our current state of knowledge.

[2] Seediness refers to whether, and to what extent, a fruit contains seeds. In commercial fruit production, reduced seediness (or "seedlessness") is often a desirable trait and may result from sterility or other mechanisms affecting seed development.