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Sort It Out: Cell Sorting Method with Data Processing Steps Patent Eligible

In XY, LLC v. Trans Ova Genetics, LC (Case 2019-1789, issued July 31, 2020), the Federal Circuit provided another example of a life sciences method claim avoiding patent ineligibility under the Alice framework at step one, altogether avoiding the “inventive concept” analysis under step two.  Most significantly, the Federal Circuit reiterated that mere recitation of an abstract idea does not necessarily mean that a claim is “directed to” that abstract idea. 

The technology described and claimed in U.S. Patent No. RE46,559 (“the ’559 Patent”) concerns flow cytometry methods of for sorting cells by computationally enhancing detected differences.  The ’559 Patent emphasizes the importance of separating sperm based on the presence of an X or Y chromosome in animal husbandry processes for obtaining offspring of a desired sex, and the challenges in doing so.  The asserted independent claim recites steps of “establishing a fluid stream” and “entraining particles,” followed by several steps of “executing instructions read from a computer readable memory” to detect signals, convert the signals into “n-dimensional parameter data,” “rotationally alter the n-dimensional parameter data,” and “real-time classify each of the individual detected particles.”  The final step, which proved critical to the Federal Circuit’s analysis, recites “using the real-time classification, sorting the individual particles with the flow cytometer.”

The district court found the claim to be directed to the abstract idea of a “mathematical equation” (Alice step one), and lacking an inventive concept because XY admitted that each element was known in the art (Alice step two).  The Federal Circuit disagreed, citing McRO, Inc. v. Bandai Namco Games Am. Inc., 837 F.3d 1299, 1312 (Fed. Cir. 2016) for the propositions that the claims should be considered “in their entirety to ascertain whether their character as a whole is directed to excluded subject matter,” and “[i]f the claims are not directed to an abstract idea, the inquiry ends.” 

Focusing on the implementation step, rather than the computational steps, the Federal Circuit concluded that “the claims are directed to a purportedly improved method of operating a flow cytometry apparatus to classify and sort particles.”  The Court likened this “improved method of operating” to the method of operating a rubber-molding press in Diamond v. Diehr, 450 U.S. 175, 184 (1981), in that “the asserted claims ‘describe in detail a step-by-step method’ for accomplishing a physical process.”  For the Federal Circuit, the recitation of formulas did not render the claims “directed to” an abstract idea because the method “incorporates applied mathematics in a purported improvement to an otherwise-known method to yield an improved result.”  As such the claims were deemed patent eligible under Alice step one.

The Federal Circuit also dismissed a comparison to the claims in Parker v. Flook, 437 U.S. 584 (1978), because the claims in Flook required “nothing more than updating an alarm limit—a number—through application of the recited formula.”  As such, the physical step at the end of the claim in XY, physically sorting the individual particles “using the real-time classification,” proved critical in rendering the claims non-abstract when considered as a whole

Takeaway:  The XY decision reminds us reciting an abstract idea (e.g., a mathematical formula) in a method claim does not render the claim patent ineligible per se.  Rather, what matters is whether the claim also incorporates that abstract idea into a physical process

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Brad M. Scheller is an experienced patent litigator and strategic counselor to start-up ventures and established businesses in the mechanical and electrical arts, with a focus in EV and battery technologies and advising clients on patent portfolio growth, management and enforcement. He represents clients before the United States Patent and Trademark Office and as lead counsel in federal district court and appellate litigation across the country.