i4i Makes the Patent World Blind

All patents receive a presumption of validity pursuant to 35 USC § 282. Courts have traditionally put this presumption into practice by requiring invalidity to be established by clear and convincing evidence. The Supreme Court reaffirmed this understanding of the presumption in Microsoft Corp v i4i Ltd Partnership. District courts have divided, however, on whether to require clear and convincing evidence when the challenger seeks to invalidate a patent for covering ineligible subject matter. The conflict originates from a concurrence written by Justice Stephen Breyer in i4i, in which he stated that a heightened standard of proof—like the clear and convincing standard—can apply only to issues of fact, not issues of law. Because subject-matter eligibility has traditionally presented an issue of law, some courts hold that subject-matter-eligibility challenges cannot be subjected to the clear and convincing standard. Other courts agree with that sentiment but would apply the clear and convincing standard to resolve any underlying issues of fact. Still others maintain that subject-matter-eligibility challenges must be established by clear and convincing evidence. This Comment resolves this ambiguity by showing that subject-mattereligibility challenges must be established by clear and convincing evidence. It compares subject-matter-eligibility challenges to two other patent validity challenges: the on-sale bar and nonobviousness. These two comparisons show that patent law has consistently failed to confine the clear and convincing standard to issues of law. In fact, the standard has been imposed without regard for the distinction between issues of law and fact. Accordingly, judges should impose the clear and convincing standard on subject-matter-eligibility challenges