NuCana (NASDAQ: NCNA) CEO reports initial share and option holdings

Rhea-AI Filing Summary

NuCana plc director and CEO Hugh Griffith has filed an initial Form 3 reporting his equity holdings in the company. He reports direct ownership of 1,000,000 Ordinary Shares and American Depositary Shares, with one entry showing 52 American Depositary Shares. According to the disclosure, each American Depositary Share represents 5,000 Ordinary Shares of NuCana plc.

The filing also lists several option awards over Ordinary Shares, all held directly. These include separate option positions over 62,499,995, 1,221,867,885, 1,544,328,984, 691,582,704 and 831,561,761 underlying Ordinary Shares, each with very low exercise prices in Pounds Sterling. Footnotes state that some options are fully vested and expire between June 20, 2035 and January 14, 2036, while others vest in annual installments through June 20, 2029 and January 14, 2030, subject to continued service.

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

Griffith Hugh

(Last) (First) (Middle)

C/O NUCANA PLC

3 LOCHSIDE WAY

(Street)

EDINBURGH EH12 9DT

(City) (State) (Zip)

UNITED STATES

(Country)

2. Date of Event Requiring Statement (Month/Day/Year)
03/18/2026

3. Issuer Name and Ticker or Trading Symbol
NuCana plc [ NCNA ]

3a. Foreign Trading Symbol

5. If Amendment, Date of Original Filed (Month/Day/Year)

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Ordinary Shares	1,000,000	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
American Depositary Shares	(1)	(1)	Ordinary Shares	52	(1)	D
Options	(2)	(2)	Ordinary Shares	62,499,995	(2)	D
Options	(3)	(3)	Ordinary Shares	1,221,867,885	(3)	D
Options	(4)	(4)	Ordinary Shares	1,544,328,984	(4)	D
Options	(5)	(5)	Ordinary Shares	691,582,704	(5)	D
Options	(6)	(6)	Ordinary Shares	831,561,761	(6)	D

Explanation of Responses:

1. Each American Depositary Share ("ADS") represents 5,000 ordinary shares, nominal value 0.0004 Pounds Sterling per share (the "Ordinary Shares"), of NuCana plc (the "Company"). ADSs have no expiration date.

2. The Ordinary Shares underlying this option have an exercise price of 0.004 Pounds Sterling, completed vesting on June 20, 2025 and expire June 20, 2035.

3. The Ordinary Shares underlying this option have an exercise price of 0.0004 Pounds Sterling, completed vesting on June 20, 2025 and expire June 20, 2035.

4. The Ordinary Shares underlying this option have an exercise price of 0.0004 Pounds Sterling, completed vesting on January 14, 2026 and expire January 14, 2036.

5. The Ordinary Shares underlying this option have an exercise price of 0.0004 Pounds Sterling and will vest as to 25% on June 20, 2026, with the remainder vesting in three equal annual installments thereafter, subject to the Reporting Person's continued service with the Company through the applicable vesting date.

6. The Ordinary Shares underlying this option have an exercise price of 0.0004 Pounds Sterling and will vest as to 25% on January 14, 2027, with the remainder vesting in three equal annual installments thereafter, subject to the Reporting Person's continued service with the Company through the applicable vesting date.

Remarks:

Exhibit 24.1 - Power of Attorney

	/s/ Ian Webster, Attorney-in-Fact for Hugh Griffith	03/18/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 3: SEC 1473 (03-26)

FAQ

What does NuCana (NCNA) CEO Hugh Griffith report in this Form 3?

Hugh Griffith reports his initial beneficial ownership in NuCana. The filing shows direct holdings of 1,000,000 Ordinary Shares, American Depositary Shares, and several large option awards over Ordinary Shares with long-dated expirations and low exercise prices.

How many NuCana (NCNA) Ordinary Shares does Hugh Griffith hold directly?

The Form 3 shows Hugh Griffith directly holding 1,000,000 Ordinary Shares of NuCana. This position is separate from his option awards, which give rights to acquire additional Ordinary Shares under various stock option grants described in the filing.

What American Depositary Share position does the NuCana (NCNA) Form 3 disclose?

The filing lists a holding of American Depositary Shares with an entry showing 52 such securities. A footnote explains that each American Depositary Share represents 5,000 Ordinary Shares of NuCana plc, and that these ADSs have no expiration date.

What option awards over NuCana (NCNA) Ordinary Shares are reported for Hugh Griffith?

The Form 3 discloses several option positions over Ordinary Shares, including grants over 62,499,995 and multiple blocks exceeding 600 million underlying shares. Footnotes detail low exercise prices in Pounds Sterling, completed vesting for some grants, and expirations between 2035 and 2036.

How do the NuCana (NCNA) options held by Hugh Griffith vest and expire?

Some options are fully vested and expire on June 20, 2035 or January 14, 2036. Other grants vest 25% on June 20, 2026 or January 14, 2027, with the balance vesting in three equal annual installments, contingent on continued service.