In T 172/95 the board did not follow the appellant/opponent's argument that for the copolymer the subsequent European application contained information not to be found in the priority document. As to the objections concerning the fractionation method the appellant could provide no evidence for his allegation that the differences which were present would result in different ethylene polymers being claimed in the priority document and in the patent in suit. In contrast, the respondent provided evidence of the contrary. Regarding the calculation methods for two parameters defining the claimed copolymer, the board pointed out that the passage not present in the priority document did not change anything in the actual method of determination of these parameters, but merely specified how a person skilled in the art would normally operate. Therefore, the introduction of the above passage into the application as filed did not change anything in the definition of the copolymer, hence did not in substance modify the teaching of the priority document. Whereas in the priority document the copolymer could have one or more melting points, in the subsequent European application the possibility of two melting points was excluded.