Mirati Therapeutics (MRTX) SC 13D/A Mirati Therapeutics / Boxer Capital ownership change

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

SCHEDULE 13D
(Rule 13d-101)

Under the Securities Exchange Act of 1934
(Amendment No. 19)*

Mirati Therapeutics, Inc.
(Name of Issuer)

Common Stock, $0.001 par value
(Title of Class of Securities)

60468T105
(CUSIP Number)

Josh La Grange

Fried, Frank, Harris, Shriver & Jacobson LLP

801 17th Street, NW, Washington, DC 20006

202-639-7497

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

January 23, 2024
(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box  ☐.

* 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 disclosures provided in a prior cover page.

The information required on 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.: 60468T105 SCHEDULE 13D/A Page 2 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Boxer Capital, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 3 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Boxer Asset Management Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	CO

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 4 of 14 Pages

1	NAMES OF REPORTING PERSONS
	MVA Investors, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 5 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Lockend Five, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Nevada
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 6 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Braslyn Ltd.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Bahamas
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	CO

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 7 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Aaron I. Davis
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States of America
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 8 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Shehan B. Dissanayake
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States of America
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 9 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Christopher Fuglesang
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States of America
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 10 of 14 Pages

1	NAMES OF REPORTING PERSONS
	Joe Lewis
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☒
				(b)	☐
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United Kingdom
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			-0-
		8	SHARED VOTING POWER
			-0-
		9	SOLE DISPOSITIVE POWER
			-0-
		10	SHARED DISPOSITIVE POWER
			-0-
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	-0-
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 11 of 14 Pages

This Amendment No. 19 (“Amendment No. 19”) amends and supplements the statement on Schedule 13D filed on November 4, 2013 (the “Original Filing”) by Boxer Capital, LLC (“Boxer Capital”), Boxer Asset Management Inc. (“Boxer Management”), MVA Investors, LLC (“MVA Investors”) and Joe Lewis, as amended by Amendment No. 1 filed on February 2, 2015, Amendment No. 2 filed on September 18, 2015, Amendment No. 3 filed on January 6, 2016 (“Amendment No. 3”), Amendment No. 4 filed on January 15, 2016 (“Amendment No. 4”), Amendment No. 5 filed on March 17, 2016, Amendment No. 6 filed on June 8, 2016, Amendment No. 7 filed on June 24, 2016, Amendment No. 8 filed on September 28, 2016, Amendment No. 9 filed on January 10, 2017, Amendment No. 10 filed on January 30, 2017, Amendment No. 11 filed on June 27, 2017, Amendment No. 12 filed on November 20, 2017, Amendment No. 13 filed on May 23, 2019, Amendment No. 14 filed on July 19, 2019, Amendment No. 15 filed on February 14, 2020, Amendment No. 16 filed on November 2, 2020, Amendment No. 17 filed on August 16, 2023 and Amendment No. 18 filed on October 12, 2023. Amendment No. 3 was an original filing for Braslyn Ltd. (“Braslyn”). Amendment No. 4 was an original filing for Aaron I. Davis, Shehan B. Dissanayake, Christopher Fuglesang and Ivan M. Lieberburg. Amendment No. 16 was an original filing for Lockend Five, LLC (“Lockend Five”). Boxer Capital, Boxer Management, MVA Investors, Braslyn, Lockend Five, Joe Lewis, Aaron I. Davis, Shehan B. Dissanayake and Christopher Fuglesang are collectively referred to herein as the “Reporting Persons.” The Original Filing, as previously amended, remains in effect except to the extent that it is amended, restated or superseded by information contained in this Amendment No. 19. Capitalized terms used and not defined in this Amendment No. 19 have the meanings set forth in the Original Filing, as previously amended.

Item 4. Purpose of Transaction.

Item 4 is hereby amended by incorporating the following:

On January 23, 2024, the Issuer filed a Form 8-K with the SEC announcing the consummation of a transaction in which the Company became a wholly owned subsidiary of Bristol-Myers Squibb Company, as described in greater detail therein (the “Merger”). As described in that 8-K, upon the effective time (the “Effective Time”) of the Merger each share of Company Stock (with certain exceptions), including each share of Common Stock then beneficially owned by the Reporting Persons, was automatically converted into the right to receive (i) cash in an amount equal to $58.00 subject to applicable withholding tax and (ii) one contingent value right representing the right to receive $12.00 in cash, without interest and subject to any applicable tax withholding upon achievement of a specified milestone is achieved (as further explained in the Form 8-K) (the consideration contemplated by (i) and (ii), together, the “Merger Consideration”). By virtue of the Merger, each then unexpired and unexercised issued and outstanding warrant to purchase shares of Common Stock issued by or on behalf of the Company (each, a “Company Warrant”) that was outstanding as of immediately prior to the Effective Time, including all those held by the Reporting Persons, was converted into the right to receive, upon exercise of such Company Warrant, the same Merger Consideration as the holder would have been entitled to receive following the Effective Time if such holder had been, immediately prior to the Effective Time, the holder of the number of shares of Common Stock then issuable upon exercise in full of such Company Warrant without regard to any limitations on exercise contained therein. Accordingly, as of January 23, 2024, the Reporting Persons ceased to beneficially own shares of Common Stock.

Item 5. Interest in Securities of the Issuer.

(a), (b)  The Reporting Persons do not have or share the right or power to vote, or to direct the vote of, or to dispose of, or direct the disposition of, any shares of Common Stock. The Reporting Persons do not beneficially own any shares of Common Stock.

(c)         Other than as reported in Forms 4 filed with the SEC, the Reporting Persons have not engaged in any transaction in the Common Stock in the past 60 days.

(d)         Other than as described herein and except as may result from indirect interests of investors in Boxer Capital and MVA Investors, no persons other than the Reporting Persons have the right to receive or the power to direct the receipt of dividends, or proceeds of sale of such securities outlined in this report.

CUSIP No.: 60468T105 SCHEDULE 13D/A Page 12 of 14 Pages

(e)        As described in Item 4, on January 23, 2024, the Reporting Persons ceased to beneficially own any shares of Common Stock.

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.

Dated: January 24, 2024

BOXER CAPITAL, LLC
By:	/s/ Aaron I. Davis
Name:	Aaron I. Davis
Title:	Chief Executive Officer
BOXER ASSET MANAGEMENT INC.
By:	/s/ Paul Higgs
Name:	Paul Higgs
Title:	Director
BRASLYN LTD.
By:	/s/ Jason Callender
Name:	Jason Callender
Title:	Director
MVA INVESTORS, LLC
By:	/s/ Aaron I. Davis
Name:	Aaron I. Davis
Title:	Authorized Signatory
LOCKEND FIVE, LLC
By:	/s/ Greg Miller
Name:	Greg Miller
Title:	Manager
JOSEPH C. LEWIS
By:	/s/ Joseph C. Lewis
	Joseph C. Lewis, Individually
AARON I. DAVIS
By:	/s/ Aaron I. Davis
	Aaron I. Davis, Individually

SHEHAN B. DISSANAYAKE
By:	/s/ Shehan B. Dissanayake
	Shehan B. Dissanayake, Individually
CHRISTOPHER FUGLESANG
By:	/s/ Christopher Fuglesang
	Christopher Fuglesang, Individually