UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13D
(AMENDMENT NO. 4)
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Motif Bio plc
(Name of Issuer)
Ordinary Shares, par value £0.01 per share
(Title of Class of Securities)
619784101
(CUSIP Number)
Nancy Tomassone
Invesco Ltd.
1555 Peachtree Street, N.E., Suite 1800
Atlanta, Georgia 30309
Telephone Number: (404) 892-0896
(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

March 29, 2019
(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.  
Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 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 (the “Exchange Act”) or otherwise subject to the liabilities of that section of the Exchange Act but shall be subject to all other provisions of the Exchange Act (however, see the Notes).
1
NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
 
Invesco Ltd.
IRS# 980557567
2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)
              (b)
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
Bermuda
 
 
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH REPORTING
PERSON WITH
7
SOLE VOTING POWER
52,724,000
8
SHARED VOTING POWER
0
9
SOLE DISPOSITIVE POWER
52,724,000
10
SHARED DISPOSITIVE POWER
0
11
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
52,724,000
12
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     ☐
13
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
14.9%
14
TYPE OF REPORTING PERSON
HC, IA
*Includes 10,908,000 shares of the Issuer’s common stock beneficially owned by the Reporting Person pursuant to warrants that may be exercised at any time.

This Amendment No. 4 (this “Amendment No. 4”) amends and supplements the statement on Schedule 13D originally filed on November 23, 2016, as amended and supplemented by that certain Amendment No. 1 filed on February 2, 2018, that certain Amendment No. 2 filed on February 11, 2019, and that certain Amendment No. 3 filed on February 15, 2019 (collectively, the “Schedule 13D” and, together with this Amendment No. 4, this “Statement”). Capitalized terms used herein and not otherwise defined have the meaning ascribed to them in the Schedule 13D.
Item 1. Security and Issuer 
This Amendment No. 4 relates to the common stock, par value £0.01 per share (the “Ordinary Shares”), of Motif Bio plc (the “Issuer”). The address of the principal executive office of the Issuer is One Tudor Street, London, EC4Y 0AH, United Kingdom.
Item 3. Source and Amount of Funds or Other Consideration 
The information set forth in Item 3 of the Schedule 13D is hereby amended and supplemented by adding the following thereto:
This Amendment No. 4 reflects the decrease in beneficial ownership percentage of the Reporting Person as the result of issuances by the Issuer increasing the Issuer’s total Ordinary Shares outstanding to 342,491,023 and is not due to any change in the number of Ordinary Shares owned by the Reporting Person.

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: April.02.2019 
INVESCO LTD.
By: /s/ Nancy Tomassone 
Name: Nancy Tomassone
Title: Global Assurance Officer