This spring, the U.S. Supreme Court will hear Laboratory Corp. of America Holdings (dba LabCorp) v. Metabolite Laboratories Inc., No. 04-607 (filed Nov. 3, 2004), a case in which it might redefine the limits of patentable subject matter. The Supreme Court will decide whether a patent that claims a method for detecting a form of vitamin B deficiency by “correlating” an increased level of an amino acid is invalid because one cannot patent “laws of nature, natural phenomena, and abstract ideas.” In a case with far-reaching implications, the Court is poised after nearly 25 years to address the core issues of patentable subject matter.

Metabolite Laboratories Inc. is the licensee of U.S. Patent No. 4,940,658 (the ’658 patent). The ’658 patent claims methods for detecting cobalamin or folate deficiency, a condition that can cause serious illness in humans, including vascular disease, cognitive dysfunction, birth defects and cancer. Cobalamin and folate are B vitamins, known as B12 and folic acid, respectively. Because these B vitamins assist in metabolizing the amino acid homocysteine, scientists have directly assayed homocysteine to screen for cobalamin and folate deficiency. However, these direct homocysteine assays were often unreliable. Researchers then discovered a relationship between elevated levels of total homocysteine and a deficiency in either cobalamin or folate. This more reliable test was the subject of claim 13 of the ’658 patent: “A method for detecting a deficiency of cobalamin or folate in warm-blooded animals comprising the steps of: assaying a body fluid for an elevated level of total homocysteine; and correlating an elevated level of total homocysteine in said body fluid with a deficiency of cobalamin or folate.”