The lower court's opinion was controversial because many commentators felt that the scope of Ariad's patent's claims went far beyond what was covered or enabled in the patent itself. As a transcription factor, NF-κB regulates over 300 genes, and NF-κB-controlled pathways are relevant to many human diseases. As many as 200 marketed drugs have mechanisms of action that may affect the NF-κB pathway. Lilly's defense is termed by some as the "Lilly written description" doctrine, as it entails the need for an extremely detailed and precise description of the action embodiment of the invention itself.