PTAB

IPR2021-01386

Berkeley Lights Inc v. University Of British Columbia

Key Events

Petition

petition

Title: System and Method for Microfluidic Cell Culture
Brief Description: The ’270 patent discloses methods for culturing single cells using a microfluidic device. The methods involve introducing cells into a device with thousands of microfluidic chambers, retaining single cells in different chambers, and exchanging cell culture medium to create and culture individual clonal cell populations.

Prior Art Relied Upon: Park, J.Y. et al., "Single cell trapping in large microwells capable of supporting cell spreading and proliferation," (Feb. 1, 2010) ("Park").
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Park discloses every element of the challenged claims. Park described a microfluidic device with a single inlet reservoir, a main channel, and an array of 10,000 triangular microwells (the claimed "chambers") for high-throughput single-cell trapping and culturing. Petitioner asserted Park's method of flowing a cell suspension through the channel, trapping single cells in microwells via recirculation flow, and flushing the system with culture media meets all steps of independent claim 1. For dependent claims 29 and 30, Petitioner contended that Park's disclosure of monitoring cell growth and its inclusion of "time lapse images" of cell trapping and images showing cell division after two days of culture anticipates the limitations of monitoring cell growth via time-lapse imaging.

Prior Art Relied Upon: Park and the general knowledge of a Person of Ordinary Skill in the Art (POSA).
Core Argument for this Ground:
- Prior Art Mapping: This ground was presented as an alternative to the anticipation argument for claims 29 and 30. Petitioner argued that even if Park did not explicitly disclose monitoring cell growth with time-lapse imaging, Park’s device was described as being "capable of supporting cell spreading and proliferation" and enabling "observation of the direct descendants of single cells."
- Motivation to Combine: These disclosures in Park would have motivated a POSA to apply the well-known and routine technique of time-lapse imaging to monitor the very cell growth and proliferation the device was designed to facilitate.
- Expectation of Success: A POSA would have had a high expectation of success, as time-lapse micrography was a conventional and widely used tool for studying cell behavior for over half a century prior to the invention.

Prior Art Relied Upon: Park and Dykstra, B., et al., "High-resolution video monitoring of hematopoietic stem cells..." (May 23, 2006) ("Dykstra").
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued Dykstra taught a detailed method for monitoring cell growth and division in custom-designed microwells. Dykstra specifically disclosed using a videotracking system to image single cells at 3-minute intervals over a four-day period to track cell division kinetics and generate clonal populations.
- Motivation to Combine: A POSA would have been motivated to combine Park's high-throughput single-cell trapping device with Dykstra’s established long-term, high-resolution monitoring technique. The combination would allow for detailed observation of the "long-term cell responses" that Park's device was intended to support.
- Expectation of Success: A POSA would have had a reasonable expectation of success, as Dykstra successfully demonstrated the technique, and the equipment used was standard for the field.

Prior Art Relied Upon: Park and Inoue, I., et al., "On-chip culture system for observation of isolated individual cells," (Aug. 9, 2001) ("Inoue").
Core Argument for this Ground:
- Prior Art Mapping: Inoue disclosed a complete culture system for single-cell cultivation, including a microchamber array, a microscope, and a digital image processor. Inoue taught using this system with time-lapse imaging to continuously observe and analyze the "time-course growth" of single E. coli cells.
- Motivation to Combine: Petitioner emphasized that Park itself expressly cited Inoue as a precedent for the "observation of the direct descendants of single cells." This direct citation would have strongly motivated a POSA reading Park to look to Inoue's methods and apply its time-lapse imaging techniques to monitor cell growth in Park's device.
- Expectation of Success: A POSA would have had a high expectation of success, given that both references reported successful application of their respective technologies and Park implicitly endorsed Inoue's methodology through citation.

Petitioner stated that no terms require express construction for the purposes of the IPR.
However, the petition's arguments were based on the claim constructions urged by the Patent Owner in co-pending district court litigation. Specifically, Petitioner adopted the Patent Owner's proposed construction of "chamber" as "an enclosed space within a microfluidic device" and its position that "inlet" should be given its plain and ordinary meaning, which does not require the inlet and outlet to be different openings.

§314(a) (Fintiv Factors): Petitioner argued against discretionary denial under Fintiv, contending that the factors, on balance, weighed against denial. Key arguments included: a stay of the parallel district court litigation had been requested; the trial date was set for December 2022, close to the FWD deadline; and the IPR was filed diligently after the Patent Owner narrowed the asserted claims in litigation. Petitioner also asserted the merits of the petition were particularly strong.
§325(d): Petitioner argued against denial based on prior art presented to the USPTO. It was argued that the primary reference, Park, and a key secondary reference, Inoue, were never before the Examiner. While Dykstra was cited on the face of the patent, it was only part of the specification's background and there was no evidence the Examiner considered its material teachings on time-lapse imaging of single cells in microwells.

Petitioner requested the Board institute an inter partes review and cancel claims 1, 29, and 30 of Patent 10,738,270 as unpatentable.