(c) except for the differences which result from the act of derivation, the variety conforms to the initial variety in the expression of the essential characteristics that result from the genotype or combination of genotypes of the initial variety. Article 17 The breeder’s right shall not extend to: – acts done privately and for non-commercial purposes; – acts done for experimental purposes; – acts done for the purpose of breeding other varieties, and also acts referred to in the second and third paragraphs of Article 16 above in respect of such other varieties on condition that: ∗ ∗ the protected variety is not used repeatedly in order to produce the new variety; the new variety is not essentially-derived from the protected variety where the latter variety is not itself an essentially-derived variety; ∗ the new variety is clearly distinguishable from the protected variety; – and to acts done by farmers for propagating purposes on their own holdings by using the product of the harvest which they have obtained by cultivating the protected variety, with the exception of fruit trees and ornamental and flower plants. Article 18 The breeder’s right shall not extend to acts concerning material of the protected variety or a variety essentially derived from the protected variety which has been sold or marketed by the breeder or with his consent, unless such acts: (a) involve further propagation of the variety in question or (b) involve an export of material of the variety, which enables the propagation of the variety, into a country which does not protect varieties of the plant genus or species to which the variety belongs, except where the exported material is for final consumption purposes. For the purposes of the first paragraph above, “material” means in relation to a variety: (a) propagating material of any kind, (b) harvested material, including entire plants and parts of plants, and (c) any product made directly from the harvested material. Article 19