T 49/83 (OJ 1984, 112) first defined the term "plant varieties" as a multiplicity of plants which were largely the same in their characteristics and remained the same within specific tolerances after every propagation cycle. Following on from this, the board in T 320/87 (OJ 1990, 71) concluded that hybrid seed and plants, lacking stability in some trait of the whole generation population, could not be classified as plant varieties within the meaning of Art. 53(b) EPC 1973. In this regard, see also T 788/07. In T 356/93 (OJ 1995, 545). The board held that plant cells as such, which with modern technology can be cultured much like bacteria and yeasts, could not be considered to fall under the definition of a plant or of a plant variety. This was confirmed by G 1/98, which stated that plant cells should be treated like microorganisms.
The term 'plant variety' is defined in R. 26(4) EPC in the same way as in Directive 98/44/EC on the legal protection of biotechnological inventions, namely as "any plant grouping within a single botanical taxon of the lowest known rank, which grouping, irrespective of whether the conditions for the grant of a plant variety are fully met, can be:
(a) defined by the expression of the characteristics that results from a given genotype or combination of genotypes,
(b) distinguished from any other plant grouping by the expression of at least one of the said characteristics, and
(c) considered as a unit with regard to its suitability for being propagated unchanged."
The words "the expression of the characteristics that results from a given genotype or combination of genotypes" used in R. 26(4)(a) EPC refer to the entire constitution of a plant or a set of genetic information. In contrast, a plant defined by single recombinant DNA sequences is not an individual plant grouping to which an entire constitution can be attributed within the above meaning. A plant defined in this way is not a concrete living being or grouping of concrete living beings but an abstract and open definition embracing an indefinite number of individual entities defined by a part of its genotype or by a property bestowed on it by that part (G 1/98, T 189/09, T 1242/06 of 31 May 2012).