Extracting information about reservoir quality from seismic data is a key challenge in exploration, appraisal and production of hydrocarbons. We demonstrate how to perform quantitative reservoir characterization by using inverse rock physics modelling on seismic inversion data. This allows us to evaluate the non-uniqueness of our predictions. We demonstrate our methodology on a gas–condensate Norwegian Sea field under appraisal and production, and perform reservoir quality predictions along a selected seismic cross-section where we have well control. Even though such a seismic dataset is more uncertain than well log data, which have been used previously in similar analysis, we still achieve reasonable and consistent predictions of reservoir quality.