Dans Impax Laboratories Inc. v. Aventis Pharmaceuticals Inc. (October 3, 2008), la U.S. Court of Appeals for the Federal Circuit a étalie les 8 facteurs suivants pour déterminer s’il y a eu ou non “undue experimentation” afin d’établir l’anticipation:
- the quantity of experimentation;
- the amount of direction or guidance present;
- the presence or absence of working examples;
- the nature of the invention;
- the state of the prior art;
- the relative skill of those in the art;
- the predictability or unpredictability of the art; and
- the breadth of the claims.