Magic Mushrooms

If a green-blue film of mold covers bread, fruit or other foodstuffs, the food is considered hazardous to health and ends up in the garbage can. In biotechnology however, molds, especially of the genus Aspergillus, are very popular. What they all have in common is that they produce a wide variety of chemicals in a CO2-neutral way. It is obvious that such innovative processes are commercially extremely interesting and must be protected from imitation, and in practice they do not pose a fundamental problem in terms of patent law.

But what if you go back one step in the process and look at the seeds from which these fantastic little bioreactors are created? Does patent protection fail here due to the provision of Art. 53(b) EPC, according to which plant or animal varieties and essentially biological processes for the production of plants or animals are excluded from patent protection?

The Amycel case

The local chamber of the European Patent Court in The Hague recently had to decide on such a fundamental issue (1). The subject of the proceedings was an action brought by Amycel LLC for an interim injunction due to alleged infringement of its European patent EP 1993350 B2. The sole subject matter of this property right, which had to survive opposition proceedings, was the hybrid Agaricus bisporus cultivated mushroom strain BR06, the culture of which had been deposited with ATCC. Specifically, the case concerned the use of this strain, which had been bred by crossing wild mushroom strains and was characterized by significantly higher yields. Amycel based the alleged patent infringement on the fact that a Polish farmer marketed a mushroom variety in the Netherlands whose genome was more than 99.5% identical to the protected strain.

The defendant argued that the patent was to be regarded as invalid from the beginning, since the patenting of mushrooms falls under the provisions of Art. 53(b) EPC, according to which plants and animals are excluded from patent protection. The new strain that Amycell had had protected was a pure breeding product, which is why only plant variety protection could be considered here; however, this did not exist. In addition, the patent proprietor itself admitted that the genomes were not 100% identical (2).

Mushrooms belong to the funghi kingdom

The Board did not agree with this view. Rather, it took the view that the provisions of Art. 53(b) EPC were to be interpreted strictly and therefore only plants and animals were excluded from patentability. Fungi, on the other hand, belong to the kingdom of Fungi, which is taxonomically distinct from the plant and animal kingdom. Such a distinction was already common practice at the time the EPC was drafted, so that it could not be said that this aspect had simply not been taken into account.

The Board also agreed with the patent proprietor’s arguments with regard to the question of identity. According to this, it was practically impossible to find a 100% match even with completely identical samples. At most, a match of 99.85% could be achieved because errors in the sequencing of the DNA could not be avoided to a small extent.

Experts’ conclusion

The decision goes far beyond the present case. Firstly, a supranational court responsible for infringement issues has ruled on the facts of the case and thus created guidelines for all 19 EU states that have so far acceded to the UPC

Second, the decision naturally also affects those mushroom varieties that are not developed by biotechnological means (e.g., CAS) but by traditional cultivation and serve as bioreactors for a wide variety of pharmaceutical raw materials, such as for example small molecules. The market value of active ingredients produced with the help of fungi was already estimated at over US$ 54 billion in 2023 (3).

However, the Board left open how high the level of similarity in the genome must be in order to justify a patent infringement. In the present case, this could be disregarded as the sequencing had produced a value that practically corresponded to 100%. However, whether a 90% match would have been sufficient, for example, remains an open question. Perhaps the pragmatic consideration that German courts apply with regard to equivalent embodiments is helpful here: according to this, such a percentage match is to be regarded as critical for an infringement offense, with which all tasks that the original strain solves are also solved at least to a reasonable extent.  This means that even inferior embodiments are sufficient for equivalence (4).

Finally, the Chamber’s decision is not entirely without contradiction: the Community Plant Variety Office has so far disregarded taxonomy issues without any objections and has indeed granted variety protection to mushrooms and oyster mushrooms. In case of doubt, it is therefore advisable to pursue both paths, patent and plant variety protection.