CareDx, Inc. v. Natera, Inc, No. 22-1027 (Fed. Cir. 2022)Annotate this Case
The patents share the same specification and are entitled “Non-Invasive Diagnosis of Graft Rejection in Organ Transplant Patients.” They discuss diagnosing or predicting organ transplant status by using methods to detect a donor’s cell-free DNA (cfDNA). When an organ transplant is rejected, the recipient’s body, through its natural immune response, destroys the donor cells, releasing cfDNA from the donated organ’s dying cells into the blood. These increased levels of donor cfDNA—which occur naturally as the organ’s condition deteriorates—can be detected and then used to diagnose the likelihood of an organ transplant rejection.
In an infringement action, the district court found the patents ineligible under 35 U.S.C. 101. The Federal Circuit affirmed. The court applied the Supreme Court’s two-part “Alice” test to determine whether the claims were patent-eligible applications of laws of nature and natural phenomena or claims that impermissibly tie up such laws and phenomena. The claims boil down to collecting a bodily sample, analyzing the cfDNA using conventional techniques, including PCR, identifying naturally occurring DNA from the donor organ, and then using the natural correlation between heightened cfDNA levels and transplant health to identify a potential rejection, none of which was inventive. This is not a case involving a method of preparation or a new measurement technique.