Guardant Health v. Natera — Court Imposes $3M Sanctions and Ethics Training on Quinn Emanuel

Background

Guardant Health and Natera are competitors in cancer diagnostics, and their long-running dispute includes Guardant’s claim that Natera engaged in false and misleading advertising about its colorectal cancer recurrence test. Natera was represented by Quinn Emanuel Urquhart & Sullivan. The misconduct that produced this sanctions order centers on Natera’s expert, Dr. Howard Hochster, and his handling of pre-publication data from the COBRA clinical trial — a Guardant-sponsored study whose early closure for higher-than-expected false positives would have supported Natera’s defense.

On September 15, 2023, Dr. Hochster sent a memo to Quinn associates Andrew Bramhall and Elle Wang that contained specific COBRA results he had obtained, in confidence, from one of the trial’s principal investigators. He flagged the data as “confidential” and “embargoed” until the January 2024 ASCO GI conference and wrote, in caps, “PLEASE DO NOT DISCUSS DETAILS with anyone else.” Quinn used the memo as the seed for a supplemental expert report served on January 31, 2024 — a month before trial — revising it to track only what had been made public when the ASCO abstract was released on January 16, 2024.

When Guardant moved to strike the late report, Quinn partner Brian Cannon told the court at the February 21, 2024 hearing that he was “not aware of any sort of early access that Dr. Hochster may have had.” That statement was incorrect, and other Quinn attorneys on the team knew it. After Guardant subpoenaed Rutgers (Dr. Hochster’s institution) and obtained emails on June 13, 2024 showing Hochster had received a draft of the COBRA abstract from a colleague on September 13, 2023 — two days before sending Quinn his “memo” — the team chose not to correct the record. Hochster also lied about whether he still possessed the relevant emails; a court-ordered forensic examination of his computer eventually proved he did.

Judge Chen had previously found that Quinn Emanuel “deliberately and knowingly misled this Court” and awarded $2,985,909.63 in compensatory sanctions covering the costs Guardant incurred when the trial was vacated, discovery was reopened, and the case was restructured around the supposedly newly discovered data. The court appointed former U.S. Attorney Ismail Ramsey as Special Master to apportion that sum and recommend any punitive measures.

The Court’s Holding

Judge Chen adopted the Special Master’s Report and Supplemental Report in full. The Quinn Emanuel parties filed only procedural objections and did not contest the substance of the Special Master’s factual findings or the recommended apportionment.

Firm-level sanctions. Quinn Emanuel is jointly and severally liable for 100% of the $2,985,909.63 compensatory award, plus a $100,000 punitive sanction under the court’s inherent authority. The firm must also develop, administer, and document an eight-hour ethics course (focused on the duty of candor and the obligations imposed by 28 U.S.C. § 1927) for every attorney on the Natera defense team. An outline of the course is due to the court by July 6, 2026.

Individual apportionment. The Special Master capped individual liability at 1–2% and concluded that one of the named attorneys bore no personal responsibility:

• Andrew Bramhall (partner) — up to 2% / approximately $58,000, plus eight hours of ethics training.
• Brian Cannon (partner) — up to 2% / approximately $58,000, plus eight hours of ethics training. Cannon made the “no early access” statement at the February 21, 2024 hearing.
• Victoria Maroulis (managing partner) — up to 2% / approximately $58,000. The Special Master found she directed the team’s strategy of relying on “facile distinctions” between the draft abstract and the data drawn from it.
• Elle Wang (associate) — up to 1% / approximately $29,000, plus eight hours of ethics training.
• Margaret Shyr (partner) — up to 1% / approximately $29,000. When Wang flagged that Hochster’s data was confidential, Shyr responded in writing: “If that data is confidential, how did Hochster get it? Maybe I don’t want to know.”
• Ryan Landes (partner) — no apportionment. The Special Master concluded he was not sufficiently culpable to bear individual liability.

Natera was absolved of any apportioned liability; the court accepted that Natera relied on its outside counsel.

Procedural objections rejected. Quinn argued that Shyr and Maroulis — initially interviewed only as witnesses — were denied due process when the Special Master later recommended apportionment as to them. The court distinguished In re Ruffalo, noting that both attorneys received a show-cause order, were given a fresh opportunity to testify or submit evidence (which they declined), and knew the underlying “charge” from the start. Quinn also argued that the $100,000 punitive sanction required beyond-a-reasonable-doubt proof. The court held that even under that heightened standard the record supports the sanction, citing the Ninth Circuit’s Coleman v. Newsom framework and noting that $100,000 is roughly 0.004% of Quinn’s 2025 revenue and 1.2% of a single equity partner’s 2025 profits.

State Bar referral. Under California Business and Professions Code § 6086.7(a)(3), the court must notify the State Bar of any judicial sanction against an attorney exceeding $1,000. The court will transmit the order, with the appended Special Master’s Reports, to the State Bar with respect to Bramhall, Cannon, Wang, Shyr, and Maroulis.

The Court’s Framing

The order opens with a sustained narrative — framed as a Professional Responsibility hypothetical — that walks through every step of the misconduct from a mid-level associate’s perspective: the expert’s memo, the partner who said “maybe I don’t want to know,” the “thin distinctions” the team relied on, and the team’s decision not to correct the record after the Rutgers production proved the expert had lied. Three pages in, the court reveals that the hypothetical is the actual factual record. Judge Chen writes that the conduct “implicates a culture of lawyering that is deeply disturbing… that takes refuge in lawyering finesse and prioritizes winning motions over acting ethically,” and is “particularly damaging to younger associates, who take their cues and learn their practice from partners who fail to model ethical behavior.”

Key Takeaways

• Personal financial exposure for litigators is real. Five attorneys — including the firm’s California managing partner — will be reported to the State Bar and bear individual joint-and-several liability ranging from roughly $29,000 to $58,000. The amounts are modest relative to firm revenue but are individually allocated, individually reportable, and individually disclosable on bar applications and conflict checks for the rest of these lawyers’ careers.
• “Maybe I don’t want to know” is not a strategy. Margaret Shyr’s contemporaneous written reaction — preserved in the team’s internal emails — is what moved her from witness to sanctioned attorney. The Special Master cited it as direct evidence of conscious avoidance.
• The duty to correct outlives the misstatement. Several of the sanctioned attorneys were not the ones who made the original misstatement at the February 21, 2024 hearing, but they were on the team when the Rutgers production proved the misstatement wrong and they declined to go back to the court. The court treats that omission as independently sanctionable.
• Expert vetting is a firm responsibility, not the expert’s. When Dr. Hochster told the team he had “no responsive documents,” the simple verification — a screen-share search of his email — was not done until a court-ordered forensic exam forced it. The court found that failure to do a “reasonable and competent inquiry” was itself sanctionable conduct under § 1927.
• Punitive sanctions can be imposed without a jury where the dollar amount is not “serious.” The court applied the Ninth Circuit’s Coleman v. Newsom proportionality test and held that a $100,000 sanction against a firm of Quinn’s size does not require a criminal jury trial — but the court still found the conduct proved beyond a reasonable doubt.

Why It Matters

This is one of the most pointed sanctions orders ever entered against an AmLaw 100 litigation firm. The dollar figures are recoverable as a cost of doing business — the firm reportedly paid over $9 million per equity partner in 2025 — but the personal State Bar referrals, the mandatory firm-wide ethics curriculum, and Judge Chen’s narrative framing make this a reputational event rather than a financial one. The court’s repeated point — that “thin distinctions” and reflexive non-correction protect no one and harm the associate-level lawyers who learn from the partners modeling that behavior — reads as much like a message to the broader litigation bar as it does a decision in this case.

In patent and life-sciences litigation specifically, where expert witnesses routinely sit at the intersection of confidential clinical data and competitive commercial interests, the order recalibrates how aggressively firms must verify what their experts know, when they learned it, and what they still possess. “Asked and answered, counselor” — Dr. Hochster’s response when Quinn pushed him a second time on whether he had any responsive emails — is now a cautionary tale, not a punchline.