PCR primers remain patent-ineligible subject matter

The Federal Circuit affirmed the Northern District of California’s summary judgment finding that patent claims related to detecting Mycobacterium tuberculosis (MTB) are patent-ineligible under 35 U.S.C. § 101. The claims recited (i) specific primers that bind MTB DNA and (ii) diagnostic methods of primer binding and amplification/detection through polymerase chain reaction (PCR). For the primer claims, the Federal Circuit cited language from its In re BRCA1- & BRCA2-Based Hereditary Cancer Test Patent Litig., 774 F.3d 755, 760 (Fed. Cir. 2014) opinion holding that primers are merely complementary sequences to naturally occurring DNA, and thus patent ineligible without more. The court further rejected the argument that the primer’s inclusion of a 3-prime end and 3-prime hydroxyl group (required by PCR) is enough of a change to create patent eligibility. The method claims were similarly found patent-ineligible: being directed to merely the relationship of identifying specific MTB nucleotides indicating the presence of MTB. The court further found that use of PCR amplification did not add an inventive concept because the process was routine by 1994. The court found inapposite arguments that the patent owner was the first to use PCR to detect MTB, a process that improved the prior techniques that could take three to eight weeks, stating: “Many groundbreaking, innovative, and brilliant discoveries have been held patent-ineligible.”

Judge O’Malley concurred, stating that the “broad language” of BRCA1 compels the conclusion. However, the concurrence questioned whether the BRCA1 opinion was supported by the specific issues and arguments in that case, and urged the court to revisit the BRCA1 conclusion en banc.  

A copy of the opinion can be found here