The IP design is often neglected by the management literature, whereas the issue of the strategic IP management begins with IP creation. This paper intends to deal with IP as an asset to be designed and focuses on IP design by ensuring novelty and inventive step of the inventions and not their quantity. By building on the most recent design theories like Conceot Knowledge design theory, this research introduces a general framework of patent design that allows controlling for " patentability " criteria, describe a patent in a unique way using actions, effects and associated knowledge and consider reasoning of person skilled in the art. Using the introduced model, the existing patent design methods are compared and their performance characterized using an introduced patent design model. The results show that patent proposal quality depends on the capacity to extend the existing knowledge combinations; to overcome the initial design reasoning of person skilled in the art and ensure sufficient inventive step and novelty. Finally, the patent design model actually demonstrates that there is an unexplored property of design theories-non-substitution-showing that the order in design is irreversible and influences the quality of results.