Patent bar Patent eligibility and utility (35 U.S.C. 101) question: claim recites a mathematical formula for calculating the optimal cure time of rubber

Patent barPatent eligibility and utility (35 U.S.C. 101)

A claim recites a mathematical formula for calculating the optimal cure time of rubber, and further recites constantly measuring mold temperature, recalculating the cure time with the formula, and automatically opening the press when the calculated time has elapsed. Under the USPTO's analysis, which conclusion is best supported?

A The claim is ineligible, because measuring temperature is extra-solution activity
B The claim fails Step 1, because formulas are not processes
C The claim is eligible only if the formula is new
D It integrates the formula into a practical application
E The claim is ineligible, because it recites a mathematical formula

Show the answer and explanation

Answer: D. It integrates the formula into a practical application

Answer: It integrates the formula into a practical application. At Step 2A prong two, a claim that recites a judicial exception is not 'directed to' it if additional elements integrate it into a practical application, for example by improving a technology or a manufacturing process. Using the formula to control when the press opens, as in Diamond v. Diehr, applies the exception in a meaningful way (MPEP 2106.04(d), 2106.05(a)). Why not the others: - Recites a formula: reciting an exception does not end the analysis. - Extra-solution activity: here the measurement and press control are integral to the improved process. - Novel formula: novelty of the exception is irrelevant to eligibility. - Step 1: the claim recites a series of steps, so it is a process. Rule: A judicial exception integrated into a practical application is eligible at Step 2A prong two. Source: MPEP § 2106.04(d), § 2106.05(a) (9th ed., Rev. 01.2024); 35 U.S.C. 101; as at Oct 2026

Common mistake

Treating any claim that recites math as ineligible.

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Original study material written from the MPEP; not a question from the current exam.Independent. Not affiliated with or endorsed by the USPTO. Verify figures and rules against current guidance before relying on them.