Ethics in Brief: More Than Foolish: Federal Court Awards $2.9M Sanction for Attorneys’ “Deliberate” Misrepresentations
By Katie Parker
Associate Professor, USD School of Law
In a scathing order last fall, a federal judge in San Francisco labeled counsel “more than foolish” for making the implausible argument that an expert witness had “no memory” of a significant number of responsive emails that the expert had failed to produce. Last year’s order resulted in evidentiary sanctions, with a decision on monetary sanctions delayed until after trial.
This summer, following a jury trial and verdict, the Court returned to the sanctions issue, and awarded $2,985.909.63 in “misconduct related fees and costs” to the opposing party. Guardant Health, Inc. v. Natera, Inc., 2025 WL 1911524, No. 21-cv-04062-EMC (N.D. Cal. July 9, 2025).[1] A special master has now been selected to make recommendations on additional issues: apportionment of the sanction among counsel and their client, further punitive sanctions, and a possible referral to the California State Bar. Id. at * 4.
The Court’s analysis highlights the interplay between expert witness practice, disclosure obligations, and the duty of candor. It also provides important guidance for federal and state practitioners alike.
The Sanctioned Conduct
The case is a long-running false advertising/unfair competition dispute between Guardant and Natera involving their competing colorectal cancer screening products. The sanctions order arose out of Natera’s submission of a supplemental expert witness report which explained the data underlying a clinical trial (the “COBRA” study) of Guardant’s product. Natera’s counsel told the court multiple times that the expert, Dr. Hochster, had just recently received the data: “I’m certainly not aware of any sort of early access that Dr. Hochster may have had … it was not until … January 2024 that the underlying clinical data … was made available to the public.” Guardant v. Natera, 21-cv-4062-EMC, ECF No. 730 at 5-6. The court accepted these representations, denied a motion to strike the supplemental expert report, delayed the trial by four months, and ordered additional discovery into the issues raised in Dr. Hochster’s supplemental report and the COBRA study.
That discovery involved a dispute over whether Dr. Hochster had any relevant emails about the COBRA study, and Natera’s counsel repeatedly represented that Dr. Hochster had done a “comprehensive search” for emails about the COBRA study and found nothing. Id. at 7.
Dr. Hochster’s employer, however, later produced dozens of detailed, relevant emails in response to a third-party subpoena. Those emails demonstrated that Dr. Hochster (1) would have had those same responsive emails, and (2) had in-depth information about the results of the COBRA study months before the data was publicly released and months before his supplemental report. Id. at 9-10.
When Guardant moved to compel production of emails between Natera’s counsel and Dr. Hochster, an in camera review of those emails revealed that Dr. Hochster had directly emailed Natera’s attorneys regarding the clinical data months before it was publicly released and months before the supplemental report was provided to Guardant’s counsel. Id. at 12-13.
In light of the above, the court observed that Natera’s counsel “knew Dr. Hochster had correspondence with the COBRA investigators and that he had a copy of the abstract” and that counsel “deliberately and knowingly misled this Court.” Id.at 13. With these findings, the court invoked its inherent sanction authority and excluded all mention of the COBRA study at trial. Following a jury trial in Natera’s favor, the court granted Guardant’s request for nearly $3 million in compensatory sanctions. 2025 WL 1911524 at *4.
Takeaways for California Attorneys
The district court did not explicitly rely on or mention the California Rules of Professional Conduct. However the court is considering a referral to the state bar, and the court’s analysis provides important reminders for California practitioners. Just a few of the many takeaways are:
- Timely Disclosures and the Duty of Competence: CPRC Rule 1.1 codifies the duty of competence, and requires attorneys to have “sufficient learning and skill…necessary for the performance of” legal services. In federal civil litigation, this entails knowing and complying with the Federal Rules of Civil Procedure. Fed. R. Civ. P. 26(e)(2) requires parties to supplement their expert disclosures “in a timely manner if the party learns that in some material respect the disclosure or response is incomplete or incorrect…” With respect to Dr. Hochster and the COBRA study data, the delay of many months in supplementing the report was not “timely.” Dr. Hochster had, via email, asked Natera’s counsel to keep the COBRA results confidential, but such a request does not override the Federal Rules of Civil Procedure or the California Rules of Professional Conduct.
- The Duty of Candor and Document Collection: Natera’s counsel represented to the court that Dr. Hochster had conducted multiple searches of his email for emails about the COBRA study. Counsel also represented that there were no responsive emails. Dr. Hochster then testified at his deposition that he conducted only one search and it was untrue to say he had searched more than once. Dr. Hochster also testified that some emails did appear when he typed the requested search terms into his email search bar, and that he personally reviewed them and decided they weren’t responsive. This deposition testimony made clear that counsel’s statements were untrue. Regardless of whether the representations were knowingly false, this scenario highlights the importance of thorough conversations with experts and other witnesses about their records and ESI. Attorneys must ask detailed questions and feel confident about the answers before making representations to the court. With one’s own client, the better approach is to not permit a witness to conduct their own email collection and review, but rather for the attorney and ESI professionals to be directly involved. While this may not be feasible with an expert witness’s files, attorneys must take all efforts needed to ensure that they understand the facts and make truthful representations to the court.
- The Duty of Candor and Expert Witnesses: A key driving factor in the court’s sanctions orders was counsel’s February 2024 statements to the effect that Dr. Hochster did not have any early access or “insider information” about the COBRA study, and therefore couldn’t have supplemented his report earlier than he did. These statements were directly disproven by a September 2023 email from Dr. Hochster to three of Natera’s lawyers with the subject line “CONFIDENTIAL to QE on COBRA.docx,” in which he attached a memo describing the results of the COBRA study. The obvious takeaway here is to be unfailingly truthful in representations to the court. But beyond that, attorneys should educate expert witnesses early on about the litigation process, and about the duty of candor and how attorneys must comply with that duty in every aspect of the litigation, including representations regarding expert witnesses.
The story is not over with respect to Guardant’s sanctions motion. Former N.D. Cal. U.S. Attorney Ismail Ramsey is serving as a special master, with a schedule requiring his report and recommendation in October of this year on the issues of (1) apportionment of the monetary sanctions and (2) further punitive sanctions and State Bar referrals. N.D. Cal. Case 21-cv-04062-EMC, Document No. 951. For now, every California attorney should review the substantive sanctions analysis in the district court’s October 2024 Order, available at Document 730 on PACER.
[1] The 2024 Order analyzing the misconduct by the Defendant, its expert witness, and its counsel is not available on Westlaw. However, it is no longer under seal and it is available on the public docket via PACER. N.D. Cal. Case No. 21-cv-04062-EMC, Document No. 730. I have recommended that Westlaw electronically publish the October 24, 2024 Order. Any attorney can make such requests at west.attysubmissions@thomson.com.
