SCHEDULE: NuCana CEO Griffith Boosts Stake to 12.0%

NuCana plc CEO Hugh S. Griffith has disclosed a 12.0% beneficial ownership stake in the company, primarily through stock options.

Summary

• Hugh S. Griffith, CEO and Director of NuCana plc, beneficially owns 2,829,961,890 ordinary shares, representing 12.0% of the company's outstanding ordinary shares as of March 18, 2026.
• This ownership comprises 1,000,000 ordinary shares acquired in 2008, 265,026 ordinary shares in the form of American Depositary Shares (ADSs) acquired in 2021 and 2022, and options to purchase 2,828,696,864 ordinary shares exercisable within 60 days of March 18, 2026.
• The ordinary shares and ADSs were acquired using personal funds, totaling 40,000 Pounds Sterling for the initial shares and 67,026.61 Pounds Sterling for the ADSs.
• The stock options were granted as part of his compensation under the NuCana plc 2020 Long Term Incentive Plan and the NuCana BioMed Limited 2016 Share Option Scheme.
• The filing of this Schedule 13D was delayed past the June 20, 2025 deadline due to inadvertent administrative oversight, including the Reporting Person undergoing extensive surgery and treatment for serious illness.

Sentiment

Score: 7

Explanation: StockSavvy.ai views this filing positively due to the CEO's substantial and increasing beneficial ownership, which signals strong confidence and alignment with shareholder interests. The late filing is a minor administrative issue, mitigated by the disclosed personal circumstances.

Positives

• The CEO, Hugh S. Griffith, holds a significant beneficial ownership stake of 12.0% in NuCana plc, indicating strong alignment with shareholder interests.
• A substantial portion of his ownership is through vested stock options, aligning his incentives with long-term company performance.
• The acquisition of shares and ADSs using personal funds demonstrates direct financial commitment to the company.

Negatives

• The Schedule 13D filing was made after the prescribed deadline of five business days following June 20, 2025, due to administrative oversight and the CEO's serious illness.

Risks

• The delay in filing the Schedule 13D due to administrative oversight and the CEO's serious illness could raise minor concerns regarding internal compliance procedures or management capacity during health challenges.

Future Outlook

Hugh S. Griffith currently holds his securities for investment purposes and does not have any immediate plans or proposals for transactions or actions related to the Issuer's corporate activities. However, he may, at any time, review or reconsider his position and potentially formulate new plans or proposals.

Management Comments

• "Acquired securities of the Issuer for investment purposes based on his belief that the Issuer's securities represented an attractive investment opportunity and in the ordinary course of his business of investing in securities for his own accounts."
• "The failure to timely file was the result of inadvertent administrative oversight in connection with the Reporting Person's executive responsibilities and related administrative constraints, including the Reporting Person undergoing extensive surgery and treatment for serious illness."
• "The Reporting Person did not seek to gain, and does not believe the Reporting Person obtained, any advantage from filing this Schedule 13D after the deadline."

Industry Context

StockSavvy.ai notes that a significant beneficial ownership stake by a company's CEO, such as Hugh S. Griffith's 12.0% in NuCana plc, typically signals strong confidence in the company's future prospects and aligns management's interests with those of public shareholders. This level of insider commitment is often viewed favorably by investors, especially in biotechnology or pharmaceutical companies where long-term vision and leadership stability are crucial.

Comparison to Industry Standards

• StockSavvy.ai observes that a 12.0% beneficial ownership by a CEO is a substantial stake, often exceeding the average insider ownership percentages seen in many publicly traded companies, particularly those with larger market capitalizations.
• For example, while some founder-led tech companies might exhibit higher insider ownership, a 12.0% stake in a biotech firm like NuCana plc demonstrates a significant personal investment and commitment, comparable to the high insider alignment seen in successful growth-stage companies where founders retain substantial control and influence.

Stakeholder Impact

• Shareholders: Likely positive, as high insider ownership often correlates with strong management incentives and long-term focus.
• Employees: No direct impact mentioned, but a stable, committed leadership could foster a positive work environment.
• Customers/Suppliers: No direct impact mentioned.
• Creditors: No direct impact mentioned.

Next Steps

• Hugh S. Griffith may, at any time and from time to time, review or reconsider his position and/or change his purpose and/or formulate plans or proposals with respect to his investment in NuCana plc.

Key Dates

Keywords

NuCana plc, Hugh S. Griffith, Schedule 13D, beneficial ownership, insider ownership, stock options, CEO stake, NUCANA, ordinary shares, ADSs