Critics of the patent system argue that ineffective patent office screening is posing an impediment to innovation. This column develops a model to examine the effect of examination, fees, and court litigation on patent quality. Results show that frontloading fees (i.e. higher fees for application versus approval), capping litigation costs, and intensifying patent office examination all lead to increases in social welfare. Simulations calibrated with existing data suggest that about 65-85% of granted patents are invalid.