6.1.5 Definition by production process 

Antibodies can be defined by the process of their production, i.e. either by the immunisation protocol of a non-human animal with a well-characterised antigen or by the specific cell line used to produce them (for more details, see F‑IV, 4.12).

However, if such a product-by-process definition is based on the immunisation by an antigen comprising a sequence less than 100% identical to a defined sequence, it does not fulfil the requirements of Art. 84, because the use of variants renders the scope of the antibodies obtained by the immunisation process unclear.