Background

The 'Nadorcott' variety was the result of a cross between the 'Murcott' mandarin and an unknown variety. It was said to be discovered in 1982 by El Bachir Nadori in the collections of the Institut National de la Recherche Agronomique, Morocco. Following an application in 1995, a unitary EU Community Plant Variety Right for the mandarin variety was granted in 2004, with an expiration date in 2029. The rights were retained as a separate UK right from January 2021. The rights are owned by the Moroccan royal family.

The variety was a commercial success because, if grown under the right conditions, the fruit is seedless. The variety has been the subject of extensive litigation, including the controversial CJEU decision (Case C‑176/18) in 2019, discussed by the IPKat here. Infringement proceedings have been ongoing in Spain and South Africa for several years.

The Seeds of the Dispute

The case against Asda concerns a competitor variety sold under the name 'Tang Gold' (or 'Tango' in some countries), which was developed by the University of California Riverside. 'Tang Gold' fruits do not have seeds because the plant does not produce viable pollen. The University filed a US plant patent application, which was granted in 2007 (PP 17,863). The plant patent describes the variety as being developed from an irradiated bud of the 'W. Murcott' cultivar, which had unknown pedigree, but that the "cultivar 'W. Murcott' from which 'Tango' was derived may be identical to a mandarin cultivar known as 'Afourer' and also as 'Nadorcott'."

The infringement case is based on the allegation that 'Tang Gold' is an essentially derived variety (EDV) of 'Nadorcott', and therefore falls within the scope of the 'Nadorcott' PVR. Mirroring the convoluted language from the UPOV Convention, an EDV is defined in the UK Plant Varieties Act 1997 in section 7(3). The concept of EDVs has been difficult and controversial, described as the "Gordian knot" of the UPOV Convention. UPOV has sought to provide clarification over the years, which culminated in the publication of new Explanatory Notes at the end of 2023. 

When it comes to interpreting the Plant Varieties Act, it should be emphasised that the Explanatory Notes are not binding on members. Nevertheless, buttressed by the new Explanatory Notes, the owners of 'Nadorcott' issued warnings to UK supermarkets against selling 'Tang Gold' mandarins without their authorisation. In 2024, the owners brought an infringement action against Sainsbury's, which settled in October. At the start of 2025, they initiated proceedings against Asda.

Stay of Proceedings Denied

When these proceedings began, the validity of the 'Nadorcott' Community PVR was still being challenged on the grounds of novelty and entitlement. The CPVO Board of Appeal and the General Court had rejected the challenge to validity. However, not long before the hearing in the Patents Court, the CJEU refused permission to appeal on 14 March 2025. 

In response, Asda filed an application at the UK Plant Variety Rights Office (PVRO) for a declaration that the 'Nadorcott' PVR is null and void on the grounds of novelty, distinctness, and entitlement. Under the UK Act, only the PVRO has jurisdiction to rule on invalidity, cancellation and suspension of a PVR (subject to judicial review). Therefore, Asda sought a stay of the infringement proceedings before the Patents Court, pending the invalidity determination.

Mr Justice Mellor rejected the application for a stay. Comparisons were drawn to the situation for European patents, addressed in IPCom v. HTC Europe [2013] EWCA Civ 1496 (covered by the IPKat here). However, Mr Justice Mellor pointed out that the situation is different for plant varieties. Whereas difficulties can arise because twin routes to revocation of a patent may be pursued at the same time through EPO opposition proceedings and in the UK courts, the same is not true for PVRs, where only the PVRO has jurisdiction, and there is no possibility of amendment of the PVR - either it is valid, or not. Therefore, Mr Justice Mellor was "unpersuaded that there is any overlap of any significance, or any real risk of inconsistent decisions." 

It was also relevant that many of Asda's validity arguments being raised before the UK PVRO had already been considered while the 'Nadorcott' variety was "bogged down for more than 8 years in the invalidity proceedings in Europe," including the hearings before specialist plant variety tribunals (the CPVO and its Board of Appeal). There was no information available about how long the validity challenge would take, but Mr Justice Mellor encouraged the UK PVRO to decide the challenge "as soon as it is able to do so." 

We will await an outcome on validity from the Plant Variety Rights Office in due course. Meanwhile, the infringement proceedings will go to trial in November 2025.

Source: https://ipkitten.blogspot.com/2025/06/no-stay-of-infringement-proceedings.html