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

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. )*

Translate Bio, Inc.

(Name of Issuer)

Common Stock, par value $0.001

(Title of Class of Securities)

89374L104

(CUSIP Number of Class of Securities)

Alec N. Litowitz

Magnetar Capital LLC

1603 Orrington Ave.

Evanston, Illinois 60201

(847) 905-4400

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

August 5, 2021

(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 Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box. ¨

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 240.13d-7(b) for other parties to whom copies are to be sent.

*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. 89374L104

SCHEDULE 13D

Page 2 of 13

1.	NAME OF REPORTING PERSON: Magnetar Financial LLC
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
	(a) ¨
	(b) x
3.	SEC USE ONLY
4.	SOURCE OF FUNDS OO
5.	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

NUMBER OF

SOLE VOTING POWER

BENEFICIALLY

OWNED BY

SHARED VOTING POWER

3,972,186

EACH REPORTING

PERSON

SOLE DISPOSITIVE POWER

WITH

10.

SHARED DISPOSITIVE POWER

3,972,186

11.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,972,186
12.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 5.26%
14.	TYPE OF REPORTING PERSON IA; OO

CUSIP No. 89374L104

SCHEDULE 13D

Page 3 of 13

1.	NAME OF REPORTING PERSON: Magnetar Capital Partners LP
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
	(a) ¨
	(b) x
3.	SEC USE ONLY
4.	SOURCE OF FUNDS OO
5.	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

NUMBER OF

SOLE VOTING POWER

BENEFICIALLY

OWNED BY

SHARED VOTING POWER

3,972,186

EACH REPORTING

PERSON

SOLE DISPOSITIVE POWER

WITH

10.

SHARED DISPOSITIVE POWER

3,972,186

11.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,972,186
12.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 5.26%
14.	TYPE OF REPORTING PERSON HC; OO

CUSIP No. 89374L104

SCHEDULE 13D

Page 4 of 13

1.	NAME OF REPORTING PERSON: Supernova Management LLC
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3.	SEC USE ONLY
4.	SOURCE OF FUNDS OO
5.	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

NUMBER OF

SOLE VOTING POWER

BENEFICIALLY

OWNED BY

SHARED VOTING POWER

3,972,186

EACH REPORTING

PERSON

SOLE DISPOSITIVE POWER

WITH

10.

SHARED DISPOSITIVE POWER

3,972,186

11.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,972,186
12.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 5.26%
14.	TYPE OF REPORTING PERSON HC; OO

CUSIP No. 89374L104

SCHEDULE 13D

Page 5 of 13

1.	NAME OF REPORTING PERSON: Alec N. Litowitz
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) ¨ (b) x
3.	SEC USE ONLY
4.	SOURCE OF FUNDS OO
5.	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6.	CITIZENSHIP OR PLACE OF ORGANIZATION United States of America

NUMBER OF

SOLE VOTING POWER

BENEFICIALLY

OWNED BY

SHARED VOTING POWER

3,972,186

EACH REPORTING

PERSON

SOLE DISPOSITIVE POWER

WITH

10.

SHARED DISPOSITIVE POWER

3,972,186

11.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,972,186
12.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 5.26%
14.	TYPE OF REPORTING PERSON HC; IN

SCHEDULE 13D

item 1.

security and issuer

This Schedule 13D (this “Statement”) relates to the common stock, $0.001 par value (the “Shares”), of Translate Bio, Inc., a company incorporated in Delaware (the “Company”). The principal executive offices of the Company is 29 Hartwell Avenue, Lexington, MA, 02421.

Item 2.

identity and background

(a) The persons filing this Statement are Magnetar Financial LLC, a Delaware limited liability company (“Magnetar Financial”), Magnetar Capital Partners LP, a Delaware limited partnership (“Magnetar Capital Partners”), Supernova Management LLC, a Delaware limited liability company (“Supernova Management”), and Alec N. Litowitz (“Mr. Litowitz”) (collectively, the “Reporting Persons”).

This Statement relates to Shares held for the accounts of each of (i) Magnetar PRA Master Fund Ltd, a Cayman Islands exempted company (“PRA Master Fund”), (ii) Magnetar Constellation Fund II-PRA LP, a Delaware limited partnership (“Constellation Fund”), and (iii) Magnetar Systematic Multi-Strategy Master Fund Ltd, a Cayman Islands exempted company, (“Systematic Master Fund”), collectively (the “Funds”).

Magnetar Financial is a Securities and Exchange Commission (“SEC”) registered investment adviser under Section 203 of the Investment Advisers Act of 1940, as amended, and manager of investment funds and managed accounts. Magnetar Financial serves as investment adviser to each of the Funds. In such capacity, Magnetar Financial exercises voting and investment power over the Shares held for the accounts of each of the Funds. Magnetar Capital Partners serves as the sole member and parent holding company of Magnetar Financial. Supernova Management is the general partner of Magnetar Capital Partners. The manager of Supernova Management is Mr. Litowitz.

(b) The business address of each of the Reporting Persons is 1603 Orrington Avenue, 13^th Floor, Evanston, Illinois 60201.

(c) Each of the Funds is a private investment fund; Magnetar Financial is a privately-held SEC registered investment adviser and manager of investment funds and managed accounts; Magnetar Capital Partners is a privately-held limited partnership and serves as the sole member and parent holding company of Magnetar Financial; Supernova Management is a privately-held limited liability company and is the general partner of Magnetar Capital Partners; and Mr. Litowitz is a citizen of the United States of America, manager of Supernova Management and Chief Executive Officer of Magnetar Financial.

(d) None of the Reporting Persons has, during the last five years, been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

(e) None of the Reporting Persons has, during the last five years, been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction as a result of which such Reporting Person was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

(f) Magnetar Financial is a Delaware limited liability company. Magnetar Capital Partners is a Delaware limited partnership. Supernova Management is a Delaware limited liability company. Mr. Litowitz is a citizen of the United States of America.

Item 3.

source and amount of funds or other consideration

The aggregate amount of funds used by the Reporting Persons in purchasing the 3,972,186 Shares reported herein on behalf of the Funds have come directly from the assets of the Funds, which may at any given time, have included margin loans made by brokerage firms in the ordinary course of business. The aggregate amount of funds used by the Reporting Persons in purchasing the Shares on behalf of the Funds was $149,589,847.15 (excluding commissions and other execution-related costs).

ITEM 4.

PURPOSE OF TRANSACTION

The Reporting Persons acquired the 3,972,186 Shares reported herein on behalf of the Funds after the public announcement of the Merger Agreement (as defined below) for purposes of receiving the merger consideration described below upon consummation of the Merger (as described below).

Each of the Reporting Persons reserves the right to acquire additional securities of the Company in the open market, in privately negotiated transactions, or otherwise, to dispose of all or a portion of the Shares and/or other securities reported in this Statement, or to change their intention with respect to any or all of the matters referred to in this Item 4.

Other than as described above in this Item 4, the Reporting Persons do not have any plans or proposals that relate to, or would result in, any actions or events specified in clauses (a) through (j) of Item 4 to Schedule 13D.

ITEM 5.

INTEREST IN SECURITIES OF THE ISSUER

The Company reported in their Form 10-Q filed on August 5, 2021 that 75,586,714 Shares were issued and outstanding as of August 2, 2021.

(a) As of the close of business August 13, 2021, each of the Reporting Persons may have been deemed to have beneficial ownership of 3,972,186 Shares, which consisted of (i) 2,276,335 Shares held for the benefit of PRA Master Fund, (ii) 1,274,223 Shares held for the benefit of Constellation Fund; and (iii) 421,628 Shares held for the benefit of Systematic Master Fund, and all such Shares represented beneficial ownership of approximately 5.26% of the Shares.

(b) As of the close of business August 13, 2021, each of the Reporting Persons may have been deemed to share the power to vote and direct the disposition of 3,972,186 Shares, which consisted of (i) 2,276,335 Shares held for the benefit of PRA Master Fund, (ii) 1,274,223 Shares held for the benefit of Constellation Fund; and (iii) 421,628 Shares held for the benefit of Systematic Master Fund, and all such Shares represented beneficial ownership of approximately 5.26% of the Shares.

(c) Except as set forth on Schedule A attached hereto and Item 6, the Funds had no transactions in the Shares during the 60 days preceding the date of filing of this Statement. All of the transactions set forth on Schedule A attached hereto were effected in the ordinary course of business of Magnetar Financial for the accounts of each of the Funds. The transactions in the Shares set forth on Schedule A were effected in open market transactions on the NASDAQ and various other trading markets.

As disclosed by the Company in the 8-K filed with the SEC on August 2, 2021:

On August 2, 2021, Translate Bio, Inc., a Delaware corporation (the “Company”), entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Sanofi, a French société anonyme (“Sanofi”), and Vector Merger Sub, Inc., a Delaware corporation and an indirect wholly owned subsidiary of Sanofi (“Purchaser”).

Pursuant to the Merger Agreement, on the terms and subject to the conditions thereof, Purchaser will commence a cash tender offer (the “Offer”) to acquire all of the outstanding shares of common stock of the Company, $0.001 par value per share (the “Shares”), at a purchase price of $38.00 per Share in cash (the “Offer Price”), without interest and subject to any withholding of taxes required by applicable legal requirements.

The obligation of Purchaser to purchase Shares tendered in the Offer is subject to the conditions set forth in the Merger Agreement, including (1) that the number of Shares validly tendered in accordance with the terms of the Offer and not validly withdrawn, considered together with all other Shares otherwise beneficially owned by Sanofi or any of its wholly owned subsidiaries (including Purchaser) (but excluding Shares tendered pursuant to guaranteed delivery procedures that have not yet been received, as defined by Section 251(h)(6) of the Delaware General Corporation Law (the “DGCL”)), would represent one more than 50% of the total number of Shares outstanding at the time of the expiration of the Offer, (2) the absence of any injunction or other order issued by a court of competent jurisdiction or law prohibiting consummation of the Offer or the Merger, (3) the expiration or early termination of the applicable waiting period (or any extension thereof) under the HSR Act, (4) the accuracy of the Company’s representations and warranties, subject to certain materiality standards set forth in the Merger Agreement and (5) compliance by the Company in all material respects with its obligations under the Merger Agreement and (6) the absence of a Material Adverse Effect (as defined in the Merger Agreement).

Following the completion of the Offer and subject to the satisfaction or waiver of certain conditions set forth in the Merger Agreement, Purchaser will merge with and into the Company, with the Company continuing as the surviving corporation and as an indirect wholly owned subsidiary of Sanofi (the “Merger”). The Company, Sanofi and Purchaser will effect the Merger after consummation of the Offer pursuant to Section 251(h) of the DGCL. At the effective time of the Merger (the “Effective Time”), the Shares then outstanding (other than Shares (1) held by the Company (or in the Company’s treasury), Sanofi or any direct or indirect wholly owned subsidiary of Sanofi (other than Purchaser), or by stockholders of the Company who have properly exercised and perfected their statutory rights of appraisal under Delaware law, or (2) irrevocably accepted for purchase in the Offer) will each be converted into the right to receive an amount in cash equal to the Offer Price (the “Merger Consideration”), without interest and subject to any withholding of taxes required by applicable legal requirements.

(d) No other person is known by the Reporting Persons to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, any Shares that are beneficially owned by the Reporting Persons.

Item 6. contracts, arrangements, understandings or relationships with respect to the securities of the issuer

Pursuant to Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, as amended, the Reporting Persons have entered into an agreement with respect to the joint filing of this Statement, and any amendment or amendments hereto.

A client of Magnetar Financial has entered into a total return swap agreement giving it economic exposure to the Company.

Magnetar Asset Management LLC (“Magnetar Asset Management”) is an SEC registered investment adviser and an affiliate of Magnetar Financial. Magnetar Capital Partners serves as the sole member and parent holding company of Magnetar Asset Management. Certain clients of Magnetar Asset Management have entered into total return swap agreements giving them economic exposure to the Company.

Except as otherwise described herein, no contracts, arrangements, understandings or similar relationships exist with respect to the securities of the Company among or between the Reporting Persons or any other person or entity.

ITEM 7.

MATERIAL TO BE FILED AS EXHIBITS

Exhibit No.

Description

99.1

Joint Filing Agreement, dated as of August 15, 2021 among the Reporting Persons.

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:August 15, 2021

	magnetar financial llc

	By: Magnetar Capital Partners LP, its Sole Member

	By:	/s/ Alec N. Litowitz
		Name: Alec N. Litowitz
		Title: Manager of Supernova Management LLC, the General Partner of Magnetar Capital Partners LP

	magnetar capital partners LP

	By:	/s/ Alec N. Litowitz
		Name: Alec N. Litowitz
		Title: Manager of Supernova Management LLC, the General Partner of Magnetar Capital Partners LP

	supernova management llc

	By:	/s/ Alec N. Litowitz
		Name: Alec N. Litowitz
		Title: Manager

	/s/ Alec N. Litowitz
	Alec N. Litowitz

SCHEDULE A

Funds

Date	Number of Shares Bought	Price Per Share($) ⁽¹⁾⁽²⁾
8/3/2021	3,184,108	37.638399 ⁽³⁾
8/4/2021	435,421	37.741383 ⁽⁴⁾
8/5/2021	181,340	37.755063 ⁽⁵⁾
8/6/2021	171,317	37.738639 ⁽⁶⁾

(1) Excludes commissions and other execution-related costs.

(2) Upon request by the staff of the Securities and Exchange Commission, full information regarding the number of shares bought or sold (as the case may be) at each separate price will be provided.

(3) Reflects a weighted average purchase price of $37.638399 per share, at prices ranging from $37.595 to $37.72 per share.

(4) Reflects a weighted average purchase price of $37.741383 per share, at prices ranging from $37.62 to $37.89 per share.

(5) Reflects a weighted average purchase price of $37.755063 per share, at prices ranging from $37.68 to $37.80 per share.

(6) Reflects a weighted average purchase price of $37.738639 per share, at prices ranging from $37.67 to $37.87 per share.

EXHIBIT INDEX

Exhibit No.

Description

99.1

Joint Filing Agreement, dated as of August 15, 2021, among the Reporting Persons.

Translate Bio, Inc. SC 13D