June 19, 2026  ·  Updated July 14, 2026  ·  United States District Court for the Southern District of New York, No. 1:26-cv-05196

By David Brunk, civil litigation attorney

Read the complaint

Barbara Wolfson v. Zoetis Alleges Breach of Fiduciary Duty for Failing to Disclose FDA Findings on Librela Product Safety

Barbara Wolfson has initiated a Verified Stockholder Derivative Complaint against Zoetis Inc., alongside its CEO Kristin C. Peck, CFO Wetteny Joseph, and several other directors and officers. Filed on June 19, 2026, in the United States District Court for the Southern District of New York, the case (No. 1:26-cv-05196) raises allegations of breach of fiduciary duty, securities fraud, and corporate misconduct.

The complaint accuses the leadership of Zoetis of making false and misleading statements regarding the safety and competitive positioning of the company's products, notably Librela. It contends these actions inflated the company's stock price artificially, leading to significant financial market repercussions when adverse realities came to light. Among the demands, Wolfson seeks reforms in the company's governance practices and internal controls, alongside damages for the allegations of misconduct against the individual defendants. The claims remain unproven pending court proceedings, and no defendants have yet responded to the allegations.

Alleged Fraud Mechanism in Zoetis Inc.

The plaintiffs claim that the Individual Defendants of Zoetis Inc. breached their fiduciary duties by failing to maintain effective internal controls, thereby allowing the company to make materially false and misleading statements. These inaccuracies pertained to product safety issues and competitive pressures, particularly involving Zoetis’ Companion Animal business—which accounts for 70% of the company’s revenue. The complaint alleges that the FDA’s adverse findings on the Librela product, along with competitive threats from Elanco, were not adequately disclosed, contributing to inflated stock prices. Individual Defendants reportedly engaged in securities fraud by making false statements about Zoetis’ product safety and competitive stature, impacting investor decision-making and artificially inflating the company’s stock value. The drop in stock price and financial performance disclosures led to significant financial market consequences.

Zoetis's internal governance is defined by its Code of Conduct, which mandates the prompt reporting of adverse events. This requirement aims to ensure transparency and safety compliance, particularly pertinent in the case of Librela, which faced an FDA "Dear Veterinarian Letter" addressing adverse events such as ataxia, seizures, and even fatalities in treated dogs (Compl. ¶67). However, the complaint alleges that such critical information was inadequately reported and that the risks were not suitably disclosed to investors or the market at large (Compl. ¶68). This purported nondisclosure is central to the plaintiff's claim of securities fraud under the Exchange Act.

Additionally, the Zoetis Code of Conduct strictly prohibits the trading of the company's securities based on material, non-public information. The plaintiffs allege that the Individual Defendants failed to act upon or disclose vital safety and competitive threats, therefore engaging in practices that may have misled shareholders and prospective investors. These allegations underscore the claim that fiduciary duties were breached, as the defendants did not uphold the standards of transparency and responsibility expected in their roles.

The failure to adequately oversee the competitive response to Elanco's product launches exacerbated Zoetis's vulnerabilities, contributing to a substantial decline in market capitalization and investor confidence.

These allegations remain unproven at this stage, and no response from the defendants has been filed.

Financial Implications

The allegations set forth in the complaint highlight significant financial implications for Zoetis Inc. and its shareholders. The plaintiff, Barbara Wolfson, contends that the company's Companion Animal business, which generates 70% of Zoetis' total revenue, was jeopardized by misleading statements and inadequate internal controls, leading to financial missteps.

According to the complaint, the Individual Defendants sold 21,210 shares while the stock was allegedly inflated, garnering upwards of $2.7 million in proceeds (Compl. ¶6). This activity is framed as an insider advantage gained through access to material non-public information, which the defendants purportedly did not disclose. Additionally, the shareholders claim that Zoetis repurchased 28.9 million of its own shares for approximately $3.8 billion. However, it is alleged that the company overpaid by about $1.3 billion for these shares due to the artificially inflated stock price, exacerbating the financial impact on the company (Compl. ¶7).

The financial consequences crystallized on May 7, 2026, as Zoetis reported troubling financial performance, leading to its stock price plummeting by more than 21%. The stock's drastic decline culminated in an approximately $10 billion wipeout of the company's market capitalization (Compl. ¶9). This event is part of the backdrop for the legal action, representing a significant loss in shareholder value attributed to the alleged mismanagement and oversight failures by the company's leadership.

These financial factors form a core part of the lawsuit's allegations, with the plaintiff seeking redress and accountability for the purported economic harm and deficient governance practices. The legal proceedings aim to address both the direct financial consequences and the underlying governance issues that allegedly led to such outcomes.

Parties and Their Roles

The derivative complaint, filed by Barbara Wolfson, seeks to represent the interests of Zoetis Inc. by challenging the conduct of several key individuals overseeing the company's operations. Barbara Wolfson, suing both individually and on behalf of the company, argues that breaches of fiduciary duty and other violations have negatively impacted Zoetis and its shareholders.

Central to Wolfson's allegations are Kristin C. Peck, the CEO of Zoetis, and Wetteny Joseph, the company's CFO. These executives, along with several directors and officers—Paul M. Bisaro, Vanessa Broadhurst, Frank A. D’Amelio, Gavin D.K. Hattersley, Sanjay Khosla, Antoinette R. Leatherberry, Michael B. McCallister, Gregory Norden, Willie M. Reed, Mark Stetter, Louise M. Parent, Robert W. Scully, and Stephanie Tilenius—are accused of failing to oversee adequate internal controls and engaging in conduct that led to the dissemination of false and misleading statements.

These positions and historical affiliations form the backdrop against which the alleged fiduciary breaches and subsequent financial impacts are framed, highlighting the roles and responsibilities of the defendants in relation to Zoetis' strategic direction and its interactions with the market.

Derivative Claims Against Defendants

The complaint raises multiple derivative claims on behalf of Zoetis Inc., alleging that the Individual Defendants breached their fiduciary duties to the company. Among the claims, the lawsuit asserts that these defendants failed to install and maintain effective internal controls over Zoetis’ Companion Animal business, which is a significant revenue driver for the firm. The filing further alleges that the defendants disseminated materially false and misleading statements about the company's financial status and its products, in violation of Section 14(a) of the Securities Exchange Act.

Additionally, the plaintiff claims that the defendants engaged in activities constituting a waste of corporate assets. Specifically, it is alleged that the company overpaid by approximately $1.3 billion for a repurchase of 28.9 million shares at inflated prices (Compl. ¶204). These actions reportedly occurred while the stock price was artificially inflated due to undisclosed adverse events and competitive pressures. Furthermore, the complaint accuses the defendants of unjust enrichment, particularly through the sale of 21,210 shares by the Individual Defendants, generating proceeds exceeding $2.7 million, during the period of alleged misinformation dissemination (Compl. ¶6).

The lawsuit also includes a claim for aiding and abetting breaches of fiduciary duty. This claim holds that the defendants acted in concert with one another to perpetuate and conceal the misinformation that inflated Zoetis’ stock. According to the complaint, this resulted in detrimental financial consequences for both the company and its shareholders, ultimately affecting the company's market capitalization and investor trust.

These derivative claims aim to hold the directors and officers of Zoetis accountable for their governance failures, seeking various forms of relief, including damages for the company. The lawsuit requests that the court declare these breaches and mandates reforms in Zoetis’ compliance and governance practices. By pursuing these claims, the plaintiff seeks to restore and protect the integrity of corporate governance at Zoetis.

Exchange Act Claims Asserted Derivatively

The complaint asserts claims under Sections 10(b), 14(a), and 21D of the Securities Exchange Act as derivative counts brought on Zoetis's behalf against the individual defendants. Specifically, the complaint accuses these defendants of committing securities fraud by disseminating false and misleading information about the company's financial health and product safety, thereby artificially inflating the stock price. The complaint also references a separate securities class action, City of Ann Arbor v. Zoetis, No. 1:26-cv-04401-JGK.

Section 10(b) and Rule 10b-5 of the Exchange Act are pivotal to the allegations, as they prohibit any act or omission resulting in fraud or deceit in connection with the purchase or sale of any security. The complaint claims that the individual defendants knowingly made false statements concerning the safety and performance of Librela, a key product in Zoetis' product lineup, and failed to disclose adverse regulatory findings from the FDA.

Violation of Section 14(a) is also asserted, centered around alleged misstatements in the company's proxy statements. According to the plaintiff, these documents obscured key details about the company's business outlook and product challenges, which in turn misled investors about the nature and extent of risks that Zoetis was facing, including competitive threats from Elanco’s products.

The allegations present a case where the market was misled by the company's communicated prospects and product safety narratives, impacting investor decisions and causing significant financial repercussions when the truth emerged. As of now, these allegations are unproven, and the defendants have yet to respond in court.

Distinctive Pleadings in the Filing

The complaint alleges that serious adverse events associated with Librela, such as ataxia and seizures in dogs, were highlighted in a letter from the FDA on December 16, 2024, which led to mandated updates in Librela's labeling. These adverse findings were significant enough to warrant changes in how the product was presented to veterinarians and the public (Compl. ¶67-68).

The filing alleges that Zoetis faced substantial competitive pressure from Elanco Animal Health's new offerings, Zenrelia and Credelio Quattro, which posed threats to Zoetis' market share, particularly in the dermatology and parasiticides segments. The complaint states that the Defendants did not properly oversee or disclose the impact of these competitive pressures, thus failing to inform shareholders about the challenges facing key product lines and the overall Companion Animal business.

These distinct claims in the complaint form part of a broader allegation of mismanagement and lack of transparency by Zoetis' leadership, suggesting that key adverse information was not disclosed as required under securities laws, impacting the investment decisions of shareholders. The alleged inadequate responses to both regulatory findings and market competition are central to the accusations of breached fiduciary duties and securities fraud.

Relief Sought and Current Procedural Posture

The complaint filed by plaintiff Barbara Wolfson in the Southern District of New York seeks several forms of relief on behalf of Zoetis Inc. She seeks a judicial finding that the Individual Defendants, including CEO Kristin C. Peck and CFO Wetteny Joseph, breached their fiduciary duties. Additionally, she demands damages against the Individual Defendants for their alleged misconduct, which she claims led to significant financial losses for Zoetis.

In terms of corporate governance, the plaintiff urges the court to order reforms to Zoetis' compliance, internal controls, and governance practices. These changes, she argues, are necessary to prevent similar issues in the future and to ensure the company's activities align with federal securities laws and internal policies.

Further, Wolfson requests the award of attorneys’ fees and associated costs incurred in prosecuting the action and demands a jury trial on all matters deemed triable by the court. This request underscores the plaintiff's position that the issues raised have sufficiently material impact to warrant full judicial scrutiny and a comprehensive public trial.

The case currently awaits the defendants' response, and no judicial determinations have been made. The claims articulated in the complaint remain allegations pending adjudication.

The allegations described here are taken from the filing and remain unproven; no responsive pleading is reflected in the source document.

The allegations described here are taken from the filing and remain unproven; no responsive pleading is reflected in the source document.

David Brunk is a civil litigation attorney. He can be reached at david@newmanbrunk.com.