Allegations of misleading financial disclosures and management failures have surfaced in a new lawsuit targeting the leadership of a publicly traded energy storage company. A shareholder has filed a verified derivative complaint in the United States District Court for the District of New Jersey, seeking to hold current and former members of the company’s board of directors and certain executive officers accountable for alleged breaches of fiduciary duties under Delaware law and violations of federal securities laws.
The complaint was submitted by Ronald F. Skaff on March 25, 2026, naming EOS Energy Enterprises, Inc. as the nominal defendant. The suit is directed at individuals including Joseph Nigro, Joseph Mastrangelo, Jeffrey Bornstein, Claude Demby, Alex Dimitrief, Jeffrey McNeil, Gregory Nixon, Nick Robinson, Marian Walters, David Urban, and Nathan Kroeker.
According to court documents reviewed by Skaff’s attorneys from Kantrowitz, Goldhamer & Graifman P.C. and Shuman, Glenn & Stecker, the case centers on events occurring between November 2025 and February 2026. During this period—the ‘Relevant Period’—the complaint alleges that company leaders issued “a series of materially false and misleading statements to stockholders,” particularly regarding financial performance projections for fiscal year 2025.
EOS Energy Enterprises describes itself as a manufacturer focused on zinc-based energy storage systems intended as alternatives to lithium-ion batteries for utility and commercial applications. The company went public in November 2020 via a merger with B. Riley Principal Merger Corp. II.
The filing outlines how optimistic revenue forecasts were made throughout 2025 by senior executives such as CEO Joseph Mastrangelo and interim CFO/CCO Nathan Kroeker. For example, in earnings calls and press releases during November 2025, leadership reaffirmed expectations for full-year revenues between $150 million and $160 million while highlighting production milestones at its Turtle Creek manufacturing facility.
On November 20, 2025—buoyed by these positive projections—the company announced it had raised approximately $458 million through a direct offering of common stock at $12.78 per share to select purchasers. Simultaneously, EOS launched a private offering totaling up to $600 million in convertible senior notes due in 2031. These funds were earmarked partly for repurchasing outstanding convertible notes due in 2030 as well as general corporate purposes.
However, according to Skaff’s complaint, “major fourth quarter issues were being concealed” from investors at this time. On February 26, 2026 before markets opened, EOS reported actual full-year revenue for 2025 was only $114.2 million—well below prior guidance—and disclosed a gross loss of $143.8 million along with an adjusted EBITDA loss of $219.1 million. Net loss attributable to shareholders reached $969.6 million.
During an earnings call that day, Chief Operating Officer John Mahaz cited several operational setbacks: “battery line downtime ran well above industry norms,” automated production quality targets took longer than expected to achieve—which led to rework costs—and supplier nonperformance caused additional delays.
Following these announcements on February 26th, shares fell over 39%, closing at $6.74 per share (down from highs above $18 earlier). The price continued declining thereafter.
The plaintiff alleges that throughout late 2025 into early 2026 the individual defendants failed their duties by issuing overly optimistic or inaccurate statements about operational capacity and financial results while not disclosing underlying problems with manufacturing processes or internal controls over forecasting accuracy: “the Company’s inadequate systems and processes prevented it from ensuring reasonably accurate guidance.” The complaint further asserts that audit committee members permitted ineffective oversight over disclosures.
Skaff brings two primary legal claims: first—a demand for contribution under sections 10(b) and 21D of the Securities Exchange Act relating to potential liability arising from ongoing securities litigation (referenced as Yung v. EOS Energy Enterprises); second—a claim for breach of fiduciary duty against all named individual defendants for failing to act with loyalty or good faith toward shareholders.
As relief on behalf of EOS Energy Enterprises itself (not personally), Skaff requests compensatory damages against individual defendants; orders directing reforms in corporate governance; coverage for legal fees; other equitable remedies; plus authorization for maintenance of this action as a derivative suit representing all shareholders’ interests.
Attorneys listed on the filing are Gary S. Graifman (Kantrowitz Goldhamer & Graifman P.C.) based in Montvale, New Jersey; Brett D. Stecker (Shuman Glenn & Stecker) based in Ardmore, Pennsylvania; no judge name is specified in the document provided. The case is identified as Case No.: 2:26-cv-03158.
Source: 226cv03158_Skaff_v_Nigro_Complaint_District_New_Jersey.pdf
