The current lack of consistency between business processes and their underlying business models lead to a lack of understanding about business process contribution to the value chain. In order to enhance understanding of business models and their impacts to business processes, consistency of value model representations is one important aspect. Examining representations - i.e. e³value, Resource Event Agent model, and the Business Object Model -concerns both grammar and method. Therefore, the paper presents in a first step an ontologic grammar evaluation of value models, which bases on the Bunge Wand Weber Representation Model. By examining conceptual representations using e³value, UML class diagram and ER modelling in context of value models, their impact to business processes is analysed evaluating the expressiveness in terms of ontologic coverage and overlap. Impact refers to the ability to transform the concepts of value models to the process level. The paper’s contribution is not the overall evaluation, but the proof of appropriateness of value modelling grammars to their potential of an enhanced user understanding.