Welcome to our dedicated page for Hyliion Holdings Corporation SEC filings (Ticker: HYLN), 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.
Hyliion Holdings Corp. filings document formal disclosures for a developer of modular power plant technology centered on the KARNO™ generator platform. Recent Form 8-K reports furnish quarterly and annual results announcements, including management updates on KARNO development, testing, customer applications, military programs, and related business milestones.
The company’s proxy materials cover board matters, shareholder voting items, executive compensation, equity awards, pay-versus-performance tables, and governance disclosures. Together, these filings provide the regulatory record for Hyliion’s operating results, public-company governance, compensation structure, and capital-market communications as it develops distributed power-generation technology.
Hyliion Holdings Corp. (HYLN) reported a Form 4 transaction for its Chief Strategy Officer, who sold 25,218 shares of common stock on November 17, 2025 at $1.66 per share. After this sale, the officer directly holds 765,250 common shares.
The filing explains that these shares were sold at the issuer’s direction under an award agreement to cover the officer’s tax withholding obligations tied to vesting dates on August 25, November 13, and November 14, 2025. An administrative error by a third-party service provider led to cash being used for August 25 taxes initially, so the related shares were instead sold on November 17, 2025, the first date in an open trading window when a sale could be completed.
Hyliion Holdings Corp. (HYLN) reported that its Chief Executive Officer, director and 10% owner Thomas J. Healy sold 159,776 shares of common stock on November 17, 2025 at a price of $1.66 per share. After this transaction, he beneficially owned 35,237,111 shares, held directly. According to the disclosure, the sale was made at the direction of the company under an award agreement that allows the issuer to sell shares to cover the reporting person’s tax withholding obligations.
The explanation notes that the sale includes shares sold to cover tax withholding tied to vesting dates on August 25, November 13, and November 14, 2025. Due to an administrative error by a third-party service provider, cash was initially used to satisfy the August 25, 2025 tax obligation, and the related share sale could not occur until the next open trading window, which began on November 17, 2025.
Hyliion Holdings Corp. (HYLN) insider Jose Miguel Oxholm, the company’s Chief Legal & Compliance Officer, filed an amended Form 4 to correct a prior report. The amendment removes an earlier reference to common shares allegedly withheld to cover taxes on a transaction dated 08/25/2025, which the company’s third-party service provider had reported in error.
The filing clarifies that no shares were actually withheld on 08/25/2025, and updates the record to show that Oxholm directly beneficially owns 813,512 shares of common stock following the reported transaction.
Hyliion Holdings Corp. (HYLN) reported an administrative correction to insider ownership reporting rather than a new stock transaction. Chief Strategy Officer Cheri Lantz filed an amended Form 4 to fix an earlier report dated August 25, 2025. The original filing had shown common shares being withheld to cover taxes, using transaction code “F,” but the company now states that no shares were actually withheld on that date due to an administrative error by a third-party service provider. After the correction, Lantz is reported as directly owning 792,997 shares of Hyliion common stock.
Hyliion Holdings Corp. insider Thomas J. Healy, the chief executive officer, director and 10% owner of HYLN, filed an amended Form 4 to correct a prior report for August 25, 2025. The earlier filing had shown shares of common stock withheld to cover taxes, but the company states this was due to an administrative error by its third-party service provider and that no shares were actually withheld on that date. Following the correction, Healy is shown as directly owning 35,396,887 shares of Hyliion common stock.
Hyliion Holdings Corp. Chief Accounting Officer Greg Standley reported an automatic share withholding related to equity compensation. On 11/14/2025, 2,275 shares of Hyliion common stock were disposed of at $1.70 per share under transaction code “F,” which indicates shares were withheld to cover tax liabilities from the vesting and distribution of restricted stock units. After this tax withholding event, Standley beneficially owns 226,417 shares of Hyliion common stock directly.
Hyliion Holdings Corp. (HYLN) Chief Commercial Officer Govindaraj Ramasamy reported automatic share withholding transactions related to equity compensation. On 11/13/2025, 4,110 shares of common stock were withheld at $1.68 per share, and on 11/14/2025, 7,397 shares were withheld at $1.70 per share. These are coded as transaction type “F,” meaning shares were withheld to cover tax liabilities arising from the vesting and distribution of restricted stock units. Following these transactions, the reporting person beneficially owned 552,454 shares of Hyliion common stock, held directly.
Hyliion Holdings Corp. officer reports tax-related share transactions. The company’s Chief Technology Officer reported multiple transactions in Hyliion common stock in mid-November 2025. On November 13, 2025, 4,110 shares were withheld at prices of $1.68 per share, and on November 14, 2025, 7,397 shares were withheld at $1.70 per share, both to cover tax liabilities tied to restricted stock unit vesting. On November 17, 2025, 9,039 shares were sold at $1.66 per share under the issuer’s award agreement to satisfy additional tax withholding obligations. After these transactions, the reporting person held 507,572 shares directly. The filing notes that the November 17 sale also corrected an earlier administrative error by a third-party service provider related to tax withholding for shares that vested on August 25, 2025.
Hyliion Holdings Corp. (HYLN) reported an insider equity update for its Chief Financial Officer, Jon Panzer. On 11/13/2025, 5,226 shares of common stock and on 11/14/2025, 9,406 shares were disposed of at prices of $1.68 and $1.70 per share, respectively. These dispositions were not open-market sales but shares withheld to cover a tax liability arising from the vesting and distribution of restricted stock units.
After these transactions, Panzer directly beneficially owned 892,225 shares of Hyliion common stock. The filing indicates this was a routine tax-related adjustment to his equity holdings, with no derivative securities reported in Table II.
Hyliion Holdings Corp. insider Joshua T. Mook, the company’s Chief Technology Officer, filed an amended Form 4 to correct a previously reported tax-withholding transaction. The earlier filing had shown shares of common stock withheld on August 25, 2025 under transaction code "F" due to an administrative error by the issuer’s third party service provider. The amendment clarifies that no shares were actually withheld on that date and updates Column 5 of Table I. Following the corrected entry, Mook is reported as beneficially owning 529,479 shares of common stock, held directly.