Welcome to our dedicated page for Ess Tech SEC filings (Ticker: GWH), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
The ESS Tech, Inc. (NYSE: GWH) SEC filings page on Stock Titan provides access to the company’s regulatory disclosures, including Forms 10-K, 10-Q and 8-K, as well as proxy statements and material agreements. These documents offer detailed insight into ESS’s long-duration iron flow energy storage business, its capital structure, governance and risk profile.
In its periodic reports, ESS describes its role as a manufacturer of long-duration energy storage systems for commercial and utility-scale applications, based on iron flow battery technology that uses iron, salt and water. Quarterly and annual reports discuss topics such as revenue, operating expenses, cash flows, financing arrangements and factors that could affect the business. Investors can review these filings to understand how ESS is funding its strategic shift to the Energy Base platform and managing its balance sheet.
ESS frequently files Current Reports on Form 8-K to disclose material events. Recent 8-K filings have covered leadership changes, including the appointment of a new Chief Executive Officer, Chief Strategy Officer and General Counsel, Chief Financial Officer and Chief Operating Officer. Other 8-Ks describe financing transactions such as an unsecured promissory note of up to $40 million with an investment fund managed by Yorkville Advisors Global, amendments to that note, and the launch of a $75 million at-the-market equity offering program under a Sales Agreement with several agents.
The company’s definitive proxy statement (DEF 14A) provides information on board composition, corporate governance, executive compensation and stockholder voting matters, including approval of share issuances related to its standby equity purchase agreement and certain warrants. These materials help investors evaluate ESS’s governance structure and shareholder approvals for key capital measures.
On Stock Titan, ESS filings are supplemented with AI-powered summaries that explain the main points of long and technical documents, highlight significant changes, and point out items such as financing obligations, equity programs and governance decisions. Users can monitor new filings as they are posted to understand how ESS’s long-duration energy storage strategy, leadership and capital plans are reflected in its official SEC disclosures.
ESS Tech, Inc. filed its Annual Report on Form 10-K for the fiscal year ended December 31, 2025. The company describes its business as a developer and manufacturer of long-duration iron flow batteries (including a patented Proton Pump) designed for ~20,000 cycles and multi-hour storage durations. The report discloses $22.0 million in cash and short-term investments and states there is substantial doubt about the company’s ability to continue as a going concern. The filing lists 27,173,757 shares outstanding as of February 27, 2026, a reported net loss of $63.4 million for 2025, an accumulated deficit of $845.8 million, approximately 315 patents granted/applied-for, and 62 full-time employees as of December 31, 2025.
ESS Tech, Inc. is calling a virtual 2026 annual meeting on May 29, 2026 at 8:00 a.m. Pacific time for holders of 27,922,991 shares of common stock as of April 6, 2026. Stockholders will elect two Class II directors, ratify KPMG LLP as auditor, and cast advisory votes on executive pay and how often future say-on-pay votes occur.
The board recommends voting for both director nominees, for KPMG’s ratification, for approving named executive officer compensation, and for holding say-on-pay votes every one year. The proxy also outlines board independence, committee structures, a prior 1-for-15 reverse stock split, and detailed 2025 compensation for senior executives.
ESS Tech, Inc. reported that director and Founding Chairman Michael Niggli has notified the company he will resign from its Board of Directors, Audit Committee, and Nominating and Corporate Governance Committee, effective as of the 2026 annual meeting of stockholders on May 29, 2026.
The company stated that Mr. Niggli’s resignation is not due to any disagreement regarding operations, policies, or practices. ESS Tech expressed gratitude for his leadership as Founding Chairman and his years of service and contributions to the company.
ESS Tech, Inc. is an early-stage long-duration energy storage company focused on iron flow batteries for grid and commercial applications. Its technology uses earth-abundant materials, targets up to 20,000 cycles without capacity fade, and is designed for safe, long-duration use in harsh temperatures.
The company remains deeply unprofitable. Revenue fell to $1.6 million in 2025 from $6.3 million in 2024, while net losses were $63.4 million in 2025 and $86.2 million in 2024, leading to an accumulated deficit of $845.8 million. Cash and cash equivalents plus short-term investments were $22.0 million as of December 31, 2025, and management discloses substantial doubt about ESS’s ability to continue as a going concern.
ESS highlights significant risks: early commercialization, manufacturing scale-up challenges, supply chain disruptions, strong competition from lithium-ion and other storage technologies, dependence on government incentives, and the need to raise additional capital. As of mid-2025, non‑affiliate equity market value was about $13.6 million, with 27,173,757 shares outstanding as of February 27, 2026.
ESS Tech, Inc. reported very early-stage commercial revenue and ongoing heavy losses for 2025 while restructuring its business and balance sheet. For the year ended December 31, 2025, revenue was $1.6 million, reflecting limited product and service sales and reductions tied to winding down legacy contracts.
The company posted a net loss of $63.4 million, improved from a $86.2 million loss in 2024, and an Adjusted EBITDA loss of $44.3 million, a 38% year-over-year improvement. Total operating expenses fell 33% to $29.7 million as research and development, sales and marketing, and general and administrative costs were all reduced.
ESS ended 2025 with $14.5 million in cash and cash equivalents, $7.5 million in short-term investments, and working capital of about $1.0 million, down from $15.8 million a year earlier. It bolstered liquidity with a $40 million financing in October 2025, an $8.6 million at-the-market equity raise, and a $15 million registered direct offering completed in January 2026, while repaying about $28.5 million of its initial Yorkville promissory note tranche.
ESS Tech, Inc. Chief Financial Officer Kate Eileen Suhadolnik reported an open-market sale of common stock. On February 20, 2026, she sold 741 shares of ESS Tech common stock at $1.54 per share.
According to the footnotes, these shares were sold specifically to cover tax withholding obligations related to the vesting of restricted stock units (RSUs). After this transaction, she directly owned 164,414 shares of ESS Tech common stock, and a portion of her holdings consists of RSUs, each representing a contingent right to receive one share of common stock.
ESS Tech, Inc. officer Kelly F. Goodman reported an open-market sale of Common Stock. On February 20, 2026, Goodman sold 2,269 shares at an average price of $1.54 per share to cover tax withholding obligations related to vesting restricted stock units. After this transaction, Goodman directly owned 215,853 shares of ESS Tech common stock.
ESS Tech, Inc. reported that its Chief Financial Officer, Kate Eileen Suhadolnik, received equity awards on February 13, 2026. She was granted 137,500 stock options with an exercise price of $0.00 per share and 137,500 shares of common stock represented by restricted stock units (RSUs).
Both the options and RSUs vest as to 1/16th on May 20, 2026, with an additional 1/16th vesting quarterly thereafter, so long as she remains a service provider to ESS Tech through each vesting date. Following the RSU grant, her directly owned common stock holdings increased to 165,155 shares.
ESS Tech, Inc. reported that company officer Kelly F. Goodman received equity awards on February 13, 2026. Goodman was granted stock options for 137,500 shares of common stock at an exercise price of $0.00 per share and now holds stock options for 137,500 shares in total. Goodman also received 137,500 shares of common stock in the form of restricted stock units (RSUs), bringing direct common share holdings to 218,122 shares after the award. The RSUs vest as to 1/16 on May 20, 2026 and 1/16 quarterly thereafter, and the options follow the same vesting schedule, in each case contingent on Goodman remaining a service provider. Each RSU represents a contingent right to receive one share of ESS Tech common stock.
ESS Tech, Inc. disclosed that funds associated with Alyeska Investment Group, L.P., Alyeska Fund GP, LLC and Anand Parekh beneficially own 1,400,000 shares of its common stock. This represents 7.14% of the company’s outstanding common shares as of a recent prospectus.
The filing shows Alyeska and Parekh share both voting and dispositive power over all 1,400,000 shares, with no sole voting or dispositive authority. The investors certify the stake is held in the ordinary course of business and not for the purpose of changing or influencing control of ESS Tech.