Until 2012, it was never seriously doubted that methods and devices for the diagnostic testing of medical conditions could be patented if they met the statutory standards of novelty and non-obviousness. In that year, however, the Supreme Court decided Mayo Collaborative Services v. Prometheus Labs, 566 US 66 (2012), which held that the diagnostic test in question was merely the application of a "law of nature," and was therefore ineligible for patent protection under Section 101 of the Patent Act. Since then, US District Courts and the USPTO Patent Trial and Appeal Board (PTAB), relying on the precedent set by Mayo, have almost routinely invalidated diagnostic testing patents as patent ineligible under Section 101, and these decisions, with few exceptions, have been upheld by the US Court of Appeals for the Federal Circuit. Former USPTO Director David Kappos, in an op-ed published May 27, 2020 on "MorningConsult.com," concludes that the post-Mayo Section 101 jurisprudence has "drastically reduced patent protection for precisely the kinds of innovation we now need so desperately" in the wake of the COVID-19 pandemic, resulting in "dramatic reductions in investment and innovation" in the diagnostic testing field.  Mr. Kappos therefore calls for Congress to step in, along the lines of legislation that has been proposed by Sen. Thom Tillis (R. NC) and Sen. Chris Coons (D. DE), to reverse what he believes is the innovation-stifling effects of Mayo and its progeny.