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SCHEDULE 13G/A

Under the Securities Exchange Act of 1934
(Amendment No. 3)*

NUCANA PLC

(Name of Issuer)

Ordinary Shares

(Title of Class of Securities)

67022C106

(CUSIP Number)

December 30, 2019

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

o Rule 13d-1(b)

o Rule 13d-1(c)

x Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 67022C106
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Morningside Venture Investments Ltd
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)		x
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization British Virgin Islands
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power 0
			6.		Shared Voting Power 0
			7.		Sole Dispositive Power 0
			8.		Shared Dispositive Power 0
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o
	11.	Percent of Class Represented by Amount in Row (9)0%
	12.	Type of Reporting Person (See Instructions) CO

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CUSIP No. 67022C106
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Frances Anne Elizabeth Richard
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)		x
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization United Kingdom
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power 0
			6.		Shared Voting Power 0
			7.		Sole Dispositive Power 0
			8.		Shared Dispositive Power 0
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o
	11.	Percent of Class Represented by Amount in Row (9)0%
	12.	Type of Reporting Person (See Instructions) IN

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CUSIP No. 67022C106
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Raymond Long Sing Tang
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)		x
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization United Kingdom
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power 0
			6.		Shared Voting Power 0
			7.		Sole Dispositive Power 0
			8.		Shared Dispositive Power 0
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o
	11.	Percent of Class Represented by Amount in Row (9)0%
	12.	Type of Reporting Person (See Instructions) IN

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CUSIP No. 67022C106
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Jill Marie Franklin
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)		x
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization United Kingdom
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power 0
			6.		Shared Voting Power 0
			7.		Sole Dispositive Power 0
			8.		Shared Dispositive Power 0
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o
	11.	Percent of Class Represented by Amount in Row (9) 0%
	12.	Type of Reporting Person (See Instructions) IN

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CUSIP No. 67022C106
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Peter Stuart Allenby Edwards
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)		x
		(b)		o
	3.	SEC Use Only
	4.	Citizenship or Place of Organization United Kingdom
Number of Shares Beneficially Owned by Each Reporting Person With			5.		Sole Voting Power 0
			6.		Shared Voting Power 0
			7.		Sole Dispositive Power 0
			8.		Shared Dispositive Power 0
	9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
	10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o
	11.	Percent of Class Represented by Amount in Row (9) 0%
	12.	Type of Reporting Person (See Instructions) IN

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Item 1.
	(a)	Name of Issuer NuCana plc
	(b)	Address of Issuer’s Principal Executive Offices 10 Lochside Place, Edinburgh, EH12 9RG, United Kingdom
Item 2.
	(a)	Name of Person Filing Morningside Venture Investments Ltd Frances Anne Elizabeth Richard Raymond Long Sing Tang Jill Marie Franklin Peter Stuart Allenby Edwards
	(b)	Address of Principal Business Office or, if none, Residence c/o THC Management Services S.A.M. 2nd Floor, Le Prince De Galles 3-5 Avenue Des Citronniers MC 98000, Monaco With copies to: Rosemary G. Reilly Wilmer Cutler Pickering Hale and Dorr LLP 60 State Street Boston, Massachusetts 02109
	(c)	Citizenship Morningside Venture Investments Ltd – British Virgin Islands Frances Anne Elizabeth Richard - United Kingdom Raymond Long Sing Tang – United Kingdom Jill Marie Franklin – United Kingdom Peter Stuart Allenby Edwards – United Kingdom
	(d)	Title of Class of Securities Ordinary Shares
	(e)	CUSIP Number 67022C106
Item 3.	If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
	(a)	o	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).
	(b)	o	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
	(c)	o	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).
	(d)	o	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8).
	(e)	o	An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);
	(f)	o	An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);
	(g)	o	A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);
	(h)	o	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
	(i)	o	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
	(j)	o	Group, in accordance with §240.13d-1(b)(1)(ii)(J).

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Item 4.	Ownership
Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.
	(a)	Amount beneficially owned: (2) Morningside Venture Investments Ltd – 0 Frances Anne Elizabeth Richard – 0 Raymond Long Sing Tang – 0 Jill Marie Franklin – 0 Peter Stuart Allenby Edwards – 0
	(b)	Percent of class:    Morningside Venture Investments Ltd – 0% Frances Anne Elizabeth Richard – 0% Raymond Long Sing Tang– 0% Jill Marie Franklin– 0% Peter Stuart Allenby Edwards – 0%
	(c)	Number of shares as to which the person has:
		(i)	Sole power to vote or to direct the vote    Morningside Venture Investments Ltd – 0 shares Frances Anne Elizabeth Richard – 0 shares Raymond Long Sing Tang – 0 shares Jill Marie Franklin – 0 shares Peter Stuart Allenby Edwards – 0 shares
		(ii)	Shared power to vote or to direct the vote     Morningside Venture Investments Ltd – 0 shares Frances Anne Elizabeth Richard – 0 shares Raymond Long Sing Tang– 0 shares Jill Marie Franklin– 0 shares Peter Stuart Allenby Edwards – 0 shares
		(iii)	Sole power to dispose or to direct the disposition of    Morningside Venture Investments Ltd – 0 shares Frances Anne Elizabeth Richard – 0 shares Raymond Long Sing Tang– 0 shares Jill Marie Franklin– 0 shares Peter Stuart Allenby Edwards – 0 shares
		(iv)	Shared power to dispose or to direct the disposition of    Morningside Venture Investments Ltd – 0 shares Frances Anne Elizabeth Richard – 0 shares Raymond Long Sing Tang – 0 shares Jill Marie Franklin – 0 shares Peter Stuart Allenby Edwards – 0 shares
(2) This statement is filed by: (i) Morningside Venture Investments Ltd., a British Virgin Islands exempted company (“MVIL”), with respect to the Ordinary Shares directly and beneficially owned by it; (ii) Frances Anne Elizabeth Richard, with respect to the Ordinary Shares beneficially owned by her as a result of her position as a director with MVIL; (iii) Raymond Long Sing Tang, with respect to the Ordinary Shares beneficially owned by him as a result of his position as a director with MVIL; (iv) Jill Marie Franklin, with respect to the Ordinary Shares beneficially owned by her as a result of her position as a director of MVIL; and (v) Peter Stuart Allenby Edwards, with respect to the Ordinary Shares beneficially owned by him as a result of his position as a director with MVIL.  Each of the foregoing is referred to as a “Reporting Person” and collectively as the “Reporting Persons.”  Frances Anne Elizabeth Richard, Raymond Long Sing Tang, Jill Marie Franklin, and Peter Stuart Allenby Edwards are the directors of MVIL and share voting and dispositive power with respect to the securities held by MVIL.  Ms. Richard, Mr. Tang, Ms. Franklin and Mr. Edwards each disclaims beneficial ownership of the securities owned directly by MVIL, except to the extent of his or her pecuniary interest therein.  MVIL is ultimately wholly beneficially owned by a family trust established by Madam Chan Tan Ching Fen.
Item 5.	Ownership of Five Percent or Less of a Class
If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following   x.
Item 6.	Ownership of More than Five Percent on Behalf of Another Person
Not applicable.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person
Not applicable.
Item 8.	Identification and Classification of Members of the Group
See attached for identification of Members of the Group.
Item 9.	Notice of Dissolution of Group
Not applicable.

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Item 10.

Certification

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. We also hereby agree to file this statement jointly pursuant to the Agreement listed on Exhibit 99.1 hereto.

	January 16, 2020
	Date
	MORNINGSIDE VENTURE INVESTMENTS LTD.
By:	/s/ Frances Anne Elizabeth Richard
	Frances Anne Elizabeth Richard, Director
	/s/ Frances Anne Elizabeth Richard
	Frances Anne Elizabeth Richard
	/s/ Raymond Long Sing Tang
	Raymond Long Sing Tang
	/s/ Jill Marie Franklin
	Jill Marie Franklin
	/s/ Peter Stuart Allenby Edwards
	Peter Stuart Allenby Edwards

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