T 0028/20 - (I) The established decisive principle

 Key points

• The Board, on inventive step: "the established decisive principle governing the answer to the question as to what a person skilled in the art would have done depends on the result he wished to obtain (T 939/92, OJ EPO 1996, 309: point 2.5.3 of the reasons).”
• “In the case in hand, it must therefore be considered that the skilled person is deemed to be merely seeking to provide further impact-modified compositions in alternative to the ones of D9 but is not wishing to necessarily keep all properties obtained with the compositions of the examples of D9 at the same level.”

However, the established decisive principle governing the answer to the question as to what a person skilled in the art would have done depends on the result he wished to obtain (T 939/92, OJ EPO 1996, 309: point 2.5.3 of the reasons). In the case in hand, it must therefore be considered that the skilled person is deemed to be merely seeking to provide further impact-modified compositions in alternative to the ones of D9 but is not wishing to necessarily keep all properties obtained with the compositions of the examples of D9 at the same level. Thus, the skilled person would consider an increase in the amount of impact-modifier even in amounts higher than the ones taught in D9 as a useful and obvious measure, in particular to further increase the impact resistance of the compositions so prepared. In doing so, the skilled person would be merely accepting possible disadvantages (which were not demonstrated in the present case but only alleged, both by the opposition division and the respondent) related to the use of higher amounts of impact modifiers. In that respect, it is further noted that it is not credible to the Board that increasing the amount of impact-modifier from a maximum of 29.4 wt.% as taught in D9 to a slightly higher amount of 30 wt.% as defined in claim 1 of the main request may be expected to lead to so dramatic changes in the properties of the composition that the skilled person would be deterred from using such an amount of impact modifier.

https://www.epo.org/law-practice/case-law-appeals/recent/t200028eu1.html