PTAB

IPR2021-01250

Berkeley Lights Inc v. University Of British Columbia

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: System and Method for Microfluidic Cell Culture
  • Brief Description: The ’936 patent relates to methods for selecting a cell, or a clone thereof, from a population of cells. The methods involve introducing cells into a microfluidic device, culturing them to create individual clonal populations within microfluidic chambers, and measuring a cell product secreted by those populations to select desired cells.

3. Grounds for Unpatentability

Ground 1: Obviousness over Lecault and Diercks - Claims 1, 2, 4-6, 9-10, 16, 18, 20-21, 24, 28-29 are obvious over Lecault in view of Diercks.

  • Prior Art Relied Upon: Lecault (a July 2011 NATURE METHODS article), and Diercks (Application # 2007/0183943).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Lecault, an article authored by several of the ’936 patent’s inventors, described a microfluidic platform that meets nearly all limitations of independent claim 1. Lecault taught a device with thousands of nanoliter-scale chambers, a single introduction port, methods for retaining individual cells in unique chambers, exchanging culture medium, and growing the cells into clonal populations. Petitioner contended the only limitation of claim 1 not disclosed by Lecault was the step of "measuring a cell product secreted by the individual clonal cell populations."
    • Motivation to Combine: Petitioner asserted a person of ordinary skill in the art (POSITA) would combine Lecault with Diercks to supply the missing limitation. Diercks, which was co-authored by an inventor of the ’936 patent, explicitly taught microfluidic systems for measuring secreted cell products (e.g., cytokines) to analyze and sort cells. Lecault itself suggested its technology would find applications in "clone selection and cell characterization," providing an express motivation to incorporate known analytical techniques like those in Diercks to achieve this characterization.
    • Expectation of Success: Both references addressed isolating and analyzing single cells in microfluidic devices. A POSITA would have had a reasonable expectation of success in implementing the well-established analyte measurement techniques from Diercks (e.g., using functionalized beads) within the cell culture chambers of Lecault's device.

Ground 2: Obviousness over Park and DiCarlo - Claims 1, 2, 5, 6, 9, 10, 16, 28-29 are obvious over Park in view of DiCarlo.

  • Prior Art Relied Upon: Park (a Feb. 2010 MICROFLUID. NANOFLUIDICS article), and DiCarlo (a Dec. 2006 ANAL. CHEM. article).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that Park disclosed a microfluidic device with a microwell array that captured single cells using recirculation flow. The device was designed to provide sufficient room for cell growth and division, thereby creating clonal populations within the microwells. Similar to the Lecault-based ground, Petitioner argued Park taught all limitations of claim 1 except for the measurement of a secreted cell product.
    • Motivation to Combine: Park provided an express motivation to combine its teachings with DiCarlo. Park cited DiCarlo directly, stating that "[s]ingle cell trapping is necessary to allow identification of differing cell phenotypes." DiCarlo was a review article that explained how microfluidic techniques could be used to isolate single cells and analyze secreted biomolecules, such as antibodies. This explicit cross-reference directed a POSITA to use the analytical methods described by DiCarlo with Park's cell-trapping device.
    • Expectation of Success: DiCarlo established that analyzing secreted products was a known technique in the art before Park was published. A POSITA would have reasonably expected success in applying the measurement techniques discussed in DiCarlo to the cells cultured in Park's device, as Park's system was amenable to such analysis.

  • Additional Grounds: Petitioner asserted claims 28 and 29 are also obvious over Lecault in view of Diercks and DiCarlo, adding DiCarlo’s teachings on antibody detection to the primary combination of Ground 1.

4. Key Technical Contentions (Beyond Claim Construction)

  • A central contention was that the challenged claims were not entitled to their earliest asserted priority date. Petitioner argued the key limitation "measuring a cell product secreted" lacked written description support in the parent ’395 Application (filed July 7, 2011). This limitation was allegedly introduced as new matter in a continuation-in-part application filed on September 28, 2012. This later effective filing date was critical, as it rendered the Lecault reference, published in July 2011, available as prior art under 35 U.S.C. §102(b).

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under §314(a) and the Fintiv factors would be inappropriate. The core arguments were that the parallel district court litigation was in its early stages, with the Board’s institution decision expected before the close of fact discovery, and that the trial date was set for after the Board's Final Written Decision (FWD) deadline. Petitioner also asserted diligence in filing the inter partes review (IPR) approximately two months after the Patent Owner narrowed the asserted claims in the litigation.
  • Petitioner also argued against denial under §325(d), contending that the primary prior art and arguments were not previously considered by the USPTO. Specifically, while Lecault was cited on the face of the patent, it was never substantively discussed or used in a rejection, likely because the examiner did not challenge the incorrect, earlier priority date. The Park and DiCarlo references were not before the examiner at all.

6. Relief Requested

  • Petitioner requested the institution of an IPR and the cancellation of claims 1, 2, 4-6, 9-10, 16, 18, 20-21, 24, and 28-29 of the ’936 patent as unpatentable.