This paper empirically examines the emerging anti-commons effect of academic patenting and licensing on knowledge production and diffusion in Taiwan. Through a dataset of 229 Taiwanese academic patent inventors, the results reveal that the anti-commons effect is not significant as expected. However, this effect has becomes more vivid in application-oriented research and disclosure delay while academic patent inventors have involved more in licensing activities. Programs to encourage academic licensing should be aware of the side effects on academic knowledge production and diffusion.