The patent at issue in the case relates to methods for detecting Cobalamine (Vitamin B12) and Folate (Folic Acid) deficiency by determining the levels of homocysteine in the body. The claim in question pertains to a method of detecting deficiency of cobalamine or folate in warm-blooded animals comprising the following steps: assaying a body fluid for an elevated level of total homocysteine and correlating the values to an elevated level of total homocysteine in said body fluid with a deficiency of cobalamine or folate.
The successor of University Patents Inc. (the patent holder), Competitive Technologies Inc., licensed the patent to Metabolite which in turn sublicensed the patent to Roche Biomedical Laboratories (now Lab Corp). Lab Corp. exercised the licensed patent and paid royalties under the License to Metabolite. For some time, LabCorp performed total homocysteine assays under the sublicense. However, after a while, it switched to another total homocysteine assay developed by Abbott Laboratories and discontinued royalty payments to Metabolite for total homocysteine assays.
In response, Metabolite sued LabCorp for infringement in the District Court of Colorado. The district court held that LabCorp was liable for contributory infringement and granted damages to a tune of seven million dollars. The court said that the doctors by co-relating levels of homocysteine to Vitamin B deficiency infringed claim 13 of the patent. As Lab Corp. supplied the data to make such an analysis, it said that Lab Corp. was liable for contributory infringement. During the proceedings, Lab Corp. argued that claim 13 was not valid because it claims a scientific principle, i.e. the relationship of homocysteine to cobalamine and folic acid deficiency and not a specific method based on it. The court rejected this argument and stated that the claim is not a scientific principle. The Federal Circuit upheld the decision of District Court on validity of the patent claim and infringement by Lab Corp.
The US Supreme Court accepted the writ of certiorari filed by Lab Corp., challenging the decision of the Federal Circuit on validity of claim 13 of the patent. The question to be decided by the court was "Whether a vaguely worded patent claim "directing a party simply to correlate test results can validly claim a monopoly over a basic scientific relationship used in medical treatment such that any doctor necessarily infringes the patent merely by thinking about the relationship after looking at a test result."