The data is frightening. The average age of folks in the U.S. diagnosed with colorectal cancer has dropped in the past 15 years to 67 from 72. According to one of our country’s leading cancer hospitals, MD Anderson, “[n]early one in nine new colon cancer cases and one in five new rectal cancer cases occur in people under age 50.” The problem is so acute that the hospital has had to start a “Young-Onset Colorectal Cancer Program,” and is leading a clinical trial tracking young patients faced with this dread diagnosis as they battle to survive the disease. Unfortunately, the rise in cases has even dipped down into the 20-29 age cohort — with many of the diagnoses of young-onset colorectal cancer patients not being made until the cancer has not only taken root, but spread. While the causes of this rise have not yet been pinpointed with accuracy, it is likely that multiple factors are at play, from lifestyles and diet to genetic predispositions.
Meanwhile, the gold standard screening mechanism for colorectal cancer — colonoscopy — only starts getting recommended (i.e., covered by insurance) for those 45 and up, except for those with a genetic disposition or who suffer from inflammatory bowel conditions like Crohn’s disease. In short, it is up to young people (and older, for that matter) to educate themselves on the risk factors for, and the early symptoms of, colorectal cancer, on top of getting colonoscopies when screening guidelines recommend them — and to take quick action if any troubling symptoms arise.
Because the invasive nature and preparation required for a colonoscopy can be a (bad) excuse for the around 40% of our fellow Americans who (wrongly) just wing it and don’t get screened, there has long been a need for noninvasive early detection mechanisms for colorectal cancer, particularly for those in the over-45 category. Putting aside the fact that getting a colonoscopy is not that bad — and surely better than treatment for a later-detected tumor as a result of delayed screening — the simple truth is that the more options patients have for screening the better. In that respect, the introduction of Cologuard after FDA-approval in 2014 has been a gamechanger. It is estimated that Cologuard generated close to $2 billion in revenue for its manufacturer, Exact Sciences, in 2024 alone. At around $500 or so per test, that means a lot of people are getting screened for colorectal cancer that might not otherwise be doing so, but for a simple, noninvasive, at-home test like Cologuard.
Not surprisingly, Exact has protected Cologuard with dozens of patents, as would be expected for a blockbuster product. And where there is a blockbuster product, competitors are often not far behind. Enter ColoSense, which was approved by the FDA in 2024, but is not yet available to order. That may change soon, however, as ColoSense’s manufacturer Geneoscopy has partnered with testing giant Labcorp to administer the test upon launch. Fearing that outcome, Exact filed a Delaware patent infringement lawsuit against Geneoscopy in November 2023, with a companion motion for a preliminary injunction that is still awaiting decision. In the meantime, the case has proceeded into discovery, with trial set for November 2026.
While it will be interesting to see how the case plays out, including how the PI motion is disposed of, the first big decision related to the dispute just came out of a different forum, the PTAB. On July 9, 2025, the PTAB cancelled all 20 issued claims of Exact’s ‘781 patent, one of the two patents asserted by Exact against Geneoscopy in the pending Delaware lawsuit. After first agreeing with Exact’s proposal for the applicable level of skill in the art, the PTAB determined that no claim construction was necessary to reach its decision on the ‘781 patent’s validity. After a quick overview of the prior art at issue, the panel then zeroed in on a dispositive issue in the IPR, the question of whether there was a nexus between Exact’s evidence of secondary considerations of nonobviousness and the challenged claims. To Exact’s chagrin, the question was answered in the negative and the challenged claims were found obvious.
To start, the panel confirmed that the burden of proof was on the patentee, Exact, to show a nexus existed. Unsurprisingly, Exact pointed to Cologuard as the product required for nexus, supporting its position with expert testimony regarding the disclosure of the Cologuard Patient Guide and the limitations of the patent claims. In addition, Exact pointed to Cologuard’s boffo sales as evidence of commercial success, alongside the fact that Cologuard represented a welcome advance in screening options for colorectal cancer — with the attendant prizes and industry acclaim that follow such advances. Lastly, Exact argued that the “ColoSense Collection Kit contains the same elements as Exact Science’ successful Cologuard Collection Kit.”
In response, Geneoscopy pointed to the robust patent portfolio protecting Cologuard to undercut the suggestion that it was the ‘781 patent carrying the load for Cologuard’s success. In particular, the PTAB noted that Exact itself had made arguments in other patent applications that “later-claimed inventions were the reasons for Cologuard’s success and satisfaction of the long-felt need.” As a result, the PTAB determined that “Cologuard is not coextensive with the challenged claims, and no nexus between the product and the challenged claims is shown on this record.” From there, it was quick work for the panel to find obviousness based on the extensive prior art raised by Geneoscopy.
Ultimately, this IPR decision illustrates the challenges faced by companies like Exact in terms of surviving obviousness challenges against individual patents in a larger portfolio, especially where that portfolio is constructed of patents claiming incremental innovations. At a minimum, Exact’s loss of one of the two patents it chose to assert in its Delaware patent case will embolden Geneoscopy to continue to fight against Exact’s patents as it works to compete in the marketplace. Without rooting for an outcome in the case, considering the huge need for effective colorectal screening mechanisms, we can only hope that patient choice in this area continues to expand. When it comes to the fight against colorectal cancer, Exact’s failure to meet the exacting nexus standard could prove the public’s gain…
Please feel free to send comments or questions to me at gkroub@kskiplaw.com or via Twitter: @gkroub. Any topic suggestions or thoughts are most welcome.
Gaston Kroub lives in Brooklyn and is a founding partner of Kroub, Silbersher & Kolmykov PLLC, an intellectual property litigation boutique, and Markman Advisors LLC, a leading consultancy on patent issues for the investment community. Gaston’s practice focuses on intellectual property litigation and related counseling, with a strong focus on patent matters. You can reach him at gkroub@kskiplaw.com or follow him on Twitter: @gkroub.
The post Exacting Nexus Standard appeared first on Above the Law.
The data is frightening. The average age of folks in the U.S. diagnosed with colorectal cancer has dropped in the past 15 years to 67 from 72. According to one of our country’s leading cancer hospitals, MD Anderson, “[n]early one in nine new colon cancer cases and one in five new rectal cancer cases occur in people under age 50.” The problem is so acute that the hospital has had to start a “Young-Onset Colorectal Cancer Program,” and is leading a clinical trial tracking young patients faced with this dread diagnosis as they battle to survive the disease. Unfortunately, the rise in cases has even dipped down into the 20-29 age cohort — with many of the diagnoses of young-onset colorectal cancer patients not being made until the cancer has not only taken root, but spread. While the causes of this rise have not yet been pinpointed with accuracy, it is likely that multiple factors are at play, from lifestyles and diet to genetic predispositions.
Meanwhile, the gold standard screening mechanism for colorectal cancer — colonoscopy — only starts getting recommended (i.e., covered by insurance) for those 45 and up, except for those with a genetic disposition or who suffer from inflammatory bowel conditions like Crohn’s disease. In short, it is up to young people (and older, for that matter) to educate themselves on the risk factors for, and the early symptoms of, colorectal cancer, on top of getting colonoscopies when screening guidelines recommend them — and to take quick action if any troubling symptoms arise.
Because the invasive nature and preparation required for a colonoscopy can be a (bad) excuse for the around 40% of our fellow Americans who (wrongly) just wing it and don’t get screened, there has long been a need for noninvasive early detection mechanisms for colorectal cancer, particularly for those in the over-45 category. Putting aside the fact that getting a colonoscopy is not that bad — and surely better than treatment for a later-detected tumor as a result of delayed screening — the simple truth is that the more options patients have for screening the better. In that respect, the introduction of Cologuard after FDA-approval in 2014 has been a gamechanger. It is estimated that Cologuard generated close to $2 billion in revenue for its manufacturer, Exact Sciences, in 2024 alone. At around $500 or so per test, that means a lot of people are getting screened for colorectal cancer that might not otherwise be doing so, but for a simple, noninvasive, at-home test like Cologuard.
Not surprisingly, Exact has protected Cologuard with dozens of patents, as would be expected for a blockbuster product. And where there is a blockbuster product, competitors are often not far behind. Enter ColoSense, which was approved by the FDA in 2024, but is not yet available to order. That may change soon, however, as ColoSense’s manufacturer Geneoscopy has partnered with testing giant Labcorp to administer the test upon launch. Fearing that outcome, Exact filed a Delaware patent infringement lawsuit against Geneoscopy in November 2023, with a companion motion for a preliminary injunction that is still awaiting decision. In the meantime, the case has proceeded into discovery, with trial set for November 2026.
While it will be interesting to see how the case plays out, including how the PI motion is disposed of, the first big decision related to the dispute just came out of a different forum, the PTAB. On July 9, 2025, the PTAB cancelled all 20 issued claims of Exact’s ‘781 patent, one of the two patents asserted by Exact against Geneoscopy in the pending Delaware lawsuit. After first agreeing with Exact’s proposal for the applicable level of skill in the art, the PTAB determined that no claim construction was necessary to reach its decision on the ‘781 patent’s validity. After a quick overview of the prior art at issue, the panel then zeroed in on a dispositive issue in the IPR, the question of whether there was a nexus between Exact’s evidence of secondary considerations of nonobviousness and the challenged claims. To Exact’s chagrin, the question was answered in the negative and the challenged claims were found obvious.
To start, the panel confirmed that the burden of proof was on the patentee, Exact, to show a nexus existed. Unsurprisingly, Exact pointed to Cologuard as the product required for nexus, supporting its position with expert testimony regarding the disclosure of the Cologuard Patient Guide and the limitations of the patent claims. In addition, Exact pointed to Cologuard’s boffo sales as evidence of commercial success, alongside the fact that Cologuard represented a welcome advance in screening options for colorectal cancer — with the attendant prizes and industry acclaim that follow such advances. Lastly, Exact argued that the “ColoSense Collection Kit contains the same elements as Exact Science’ successful Cologuard Collection Kit.”
In response, Geneoscopy pointed to the robust patent portfolio protecting Cologuard to undercut the suggestion that it was the ‘781 patent carrying the load for Cologuard’s success. In particular, the PTAB noted that Exact itself had made arguments in other patent applications that “later-claimed inventions were the reasons for Cologuard’s success and satisfaction of the long-felt need.” As a result, the PTAB determined that “Cologuard is not coextensive with the challenged claims, and no nexus between the product and the challenged claims is shown on this record.” From there, it was quick work for the panel to find obviousness based on the extensive prior art raised by Geneoscopy.
Ultimately, this IPR decision illustrates the challenges faced by companies like Exact in terms of surviving obviousness challenges against individual patents in a larger portfolio, especially where that portfolio is constructed of patents claiming incremental innovations. At a minimum, Exact’s loss of one of the two patents it chose to assert in its Delaware patent case will embolden Geneoscopy to continue to fight against Exact’s patents as it works to compete in the marketplace. Without rooting for an outcome in the case, considering the huge need for effective colorectal screening mechanisms, we can only hope that patient choice in this area continues to expand. When it comes to the fight against colorectal cancer, Exact’s failure to meet the exacting nexus standard could prove the public’s gain…
Please feel free to send comments or questions to me at [email protected] or via Twitter: @gkroub. Any topic suggestions or thoughts are most welcome.
Gaston Kroub lives in Brooklyn and is a founding partner of Kroub, Silbersher & Kolmykov PLLC, an intellectual property litigation boutique, and Markman Advisors LLC, a leading consultancy on patent issues for the investment community. Gaston’s practice focuses on intellectual property litigation and related counseling, with a strong focus on patent matters. You can reach him at [email protected] or follow him on Twitter: @gkroub.
