Welcome to our dedicated page for Lyell Immunopharma SEC filings (Ticker: LYEL), 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.
Lyell Immunopharma filings document the regulatory record of a Nasdaq-listed clinical biotechnology company developing next-generation CAR T-cell therapies. Its 8-K reports furnish operating results and business updates for ronde-cel in large B-cell lymphoma and LYL273 in metastatic colorectal cancer and other GCC-expressing cancers, along with cash, financing and clinical-program disclosures.
The company’s filings also cover material agreements, including licensing rights for LYL273, and governance matters such as annual-meeting proposals, director elections, auditor ratification, executive compensation votes, officer appointments and compensatory arrangements. Securities disclosures identify Lyell’s common stock listed on the Nasdaq Global Select Market.
Lyell Immunopharma, Inc. (LYEL) reported that Chief Medical Officer David Shook sold 500 shares of common stock on September 10, 2026 in an open-market transaction primarily to cover a tax withholding obligation from the settlement of vested restricted stock units. The shares were sold at a weighted average price of $12.70 per share, within a range of $12.32 to $12.70 per share. After this sale, Shook directly holds 20,423 shares of Lyell common stock, and no Rule 10b5-1 trading plan is reported for this transaction.
Lyell Immunopharma, Inc. (LYEL) reported that its Chief Medical Officer, Jarrad Mattieu Aguirre, received a stock option grant for 47,500 shares of common stock on September 10, 2026. The option has an exercise price of $12.20 per share and expires on September 9, 2036. According to the vesting terms, 12.5% of the option shares will vest on February 28, 2027, with the remainder vesting in equal monthly installments over the following 42 months, subject to continued service.
After this award, Aguirre holds 20,279 shares of common stock directly, which include 14,451 restricted stock units that vest quarterly over a thirty-month period following July 9, 2026, also conditioned on continued service. No Rule 10b5-1 trading plan is reported for these transactions.
Lyell Immunopharma, Inc. (LYEL) reported the initial equity holdings of its Chief Medical Officer, Jarrad Mattieu Aguirre. He holds 20,279 shares of Common Stock, including 14,451 restricted stock units (RSUs) that vest quarterly over thirty months following July 9, 2026, subject to continued service. He also holds three option awards to purchase Common Stock: options over 46,249 shares at $11.64 per share expiring February 12, 2035; 35,000 shares at $23.71 expiring February 9, 2036; and 15,000 shares at $19.20 expiring May 10, 2036, each subject to specified time-based vesting schedules.
Lyell Immunopharma, Inc. (LYEL) reported that it has successfully completed the planned technology transfer for its GCC-targeted CAR T-cell candidate LYL273 to the LyFE Manufacturing Center in Bothell, Washington, following review by the FDA. LyFE is implementing an improved manufacturing process and updated analytical methods to enhance manufacturing performance and increase capacity.
The ongoing Phase 1/2 trial of LYL273 in relapsed/refractory metastatic colorectal cancer continues to enroll patients to determine a recommended Phase 2 dose and optimize the safety management plan. Additional clinical data and a planned End-of-Phase 1 FDA meeting are now expected in 2027. Earlier trial data showed gastrointestinal prophylaxis reduced Grade ≥ 2 diarrhea/colitis from 55% without prophylaxis to 10% with prophylaxis, and LyFE is expected to have capacity to manufacture more than 1,200 CAR T-cell doses per year.
Lyell Immunopharma, Inc. (LYEL) reported that its President and CEO, Lynn Seely, had an automatic sale of 9,589 shares of common stock on 2026-08-21 at $15.54 per share. The shares were sold to cover a tax withholding obligation from vested restricted stock units, leaving 63,899 shares held directly.
Lyell Immunopharma, Inc. (LYEL) reported that its Chief Operating Officer, Stephen J. Hill, had 989 shares of common stock automatically sold on 2026-08-21 at $15.54 per share. According to the disclosure, the sale was made to cover a tax withholding obligation arising from the settlement of vested restricted stock units, leaving 16,816 shares held directly.
Lyell Immunopharma, Inc. (LYEL) reported an insider transaction by Chief Scientific Officer Gary K. Lee. On 2026-08-21, 1,457 shares of common stock were sold at $15.54 per share. According to the disclosure, these shares were automatically sold to cover a tax withholding obligation from the settlement of vested restricted stock units, leaving 16,220 shares held directly after the transaction.
Lyell Immunopharma, Inc. received an updated beneficial ownership report from Foresite Capital-affiliated funds and James B. Tananbaum. The group reports beneficial ownership of 653,328 shares of common stock, representing 2.7% of the class, based on 24,505,141 shares outstanding as of August 3, 2026. Foresite Capital Fund V, L.P. holds 476,386 shares (1.9%) and Foresite Capital Opportunity Fund V, L.P. holds 176,942 shares (0.7%). Foresite Capital Fund IV, L.P. and its related management entity report 0 shares. Voting and dispositive power over the fund-held shares may be deemed to reside with their respective general partners and ultimately with Tananbaum, who signs pursuant to an Agreement of Joint Filing.
Lyell Immunopharma, Inc. officer Veronica Sanchez Bulis, VP and Corporate Controller, reported a sale of 621 shares of common stock on 2026-08-10 at a weighted average price of $14.34 per share, with sale prices ranging from $14.20 to $14.34. According to the disclosure, the shares were automatically sold to cover tax withholding obligations arising from the settlement of vested restricted stock units, rather than as a discretionary open-market sale. Following this transaction, Bulis directly holds 14,799 shares of Lyell Immunopharma common stock.
Lyell Immunopharma, Inc. Chief Scientific Officer Gary K. Lee reported an automatic sale of 131 shares of common stock on 2026-08-10 at a weighted average price of $14.34 per share. The shares were sold to satisfy a tax withholding obligation from the settlement of vested restricted stock units, leaving 17,677 shares held directly.