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

SCHEDULE 13G


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

Arconic Inc.
(Name of Issuer)


Common Stock
(Title of Class Securities)


03965L100
(CUSIP Number)


December 31, 2018
(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which
this Schedule is filed:
[x]	Rule 13d-1(b)
[ ]	Rule 13d-1(c)
[ ]	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 disclosure 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).
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 control number.


CUSIP No.03965L100


1
NAME OF REPORTING PERSONS.
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).
FIRST PACIFIC ADVISORS, LP
20-1362771


2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
(A)  [ ]
(B)  [ ]


3
SEC USE ONLY



4
CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE





NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH


5
SOLE VOTING POWER




6
SHARED VOTING POWER
26,188,451



7
SOLE DISPOSITIVE POWER




8
SHARED DISPOSITIVE POWER
26,188,451

9
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
26,188,451


10
CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS)



11
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
5.4

12
TYPE  OF REPORTING PERSON (SEE INSTRUCTIONS)
IA




1
NAME OF REPORTING PERSONS.
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).
J. RICHARD ATWOOD


2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
(A)  [ ]
(B)  [ ]


3
SEC USE ONLY



4
CITIZENSHIP OR PLACE OF ORGANIZATION
UNITED STATES





NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH


5
SOLE VOTING POWER



6
SHARED VOTING POWER
26,188,451



7
SOLE DISPOSITIVE POWER




8
SHARED DISPOSITIVE POWER
26,188,451

9
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

26,188,451

10
CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS)



11
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
5.4

12
TYPE  OF REPORTING PERSON (SEE INSTRUCTIONS)
HC, IN

?

1
NAME OF REPORTING PERSONS.
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).
STEVEN T. ROMICK


2
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
(A)  [ ]
(B)  [ ]


3
SEC USE ONLY



4
CITIZENSHIP OR PLACE OF ORGANIZATION
UNITED STATES





NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH


5
SOLE VOTING POWER




6
SHARED VOTING POWER
26,188,451



7
SOLE DISPOSITIVE POWER




8
SHARED DISPOSITIVE POWER
26,188,451

9
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
26,188,451


10
CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS)



11
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
5.4

12
TYPE  OF REPORTING PERSON (SEE INSTRUCTIONS)
HC, IN



Item 1.
	(a)	Name of Issuer
	Arconic Inc.

	(b)	Address of Issuer?s Principal Executive Offices
	390 Park Avenue, New York, NY 10022-4608


Item 2.
	(a)	Name of Person Filing
This Schedule 13G is being filed on behalf of First
Pacific Advisors, LP, a Delaware limited partnership
(?FPA?), J. Richard Atwood, and Steven T. Romick, each a
Director of General Partner (each, a ?Reporting Person?).
	(b)	Address of Principal Business office or, if None,
		Residence
		The address for each Reporting Person is as follows:
		11601 Wilshire Blvd., Suite 1200, Los Angeles, CA
		90025
(c)	Citizenship
FPA is a Delaware limited partnership
J. Richard Atwood is a United States citizen
Steven T. Romick is a United States citizen
(d) 	Title of Class Securities
Common Stock
(e)	CUSIP Number
		03965L100
Item 3.	If this statement is filed pursuant to Section 240.13d-
1(b), or 240.13d-2(b) or (c), check whether the person filing is
a:
(a)	[ ]	Broker or dealer registered under Section 15 of
the Act (15 U.S.C. 78c).



(b)	[ ]	Bank as defined in Section 3(a)(6) of the Act (15
U.S.C. 78c).

(c)	[ ]	Insurance company as defined in Section 3(a)(19)
of the Act (15 U.S.C. 78c).

(d)	[ ]	Investment company registered under Section 8 of
the Investment Company Act (15 U.S.C. 80a-8).

(e)	[X]	An investment adviser in accordance with Section
240.13d-1(b)(1)(ii)(E).*

(f)	[ ]	An employee benefit plan or endowment fund in
accordance with Section 240.13d-1(b)(ii)(F).

(g)	[X]	A parent holding company or control person in
accordance with Section 240.13d-1(b)(1)(ii)(G).**

(h)	[ ]	A savings association as defined in Section 3(b)
of the Federal Deposit Insurance Act (12 U.S.C.
1813).

(i)	[ ]	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)	[ ]	Group in accordance with Section 240.13d-
1(b)(ii)(J).

	*FPA is an investment adviser in accordance with
	  Section 240.13d-1(b)(1)(ii)(E).
	**J Richard Atwood and Steven T. Romick are
    control person(s) in
	   accordance with Section 240.13d-
   1(b)(1)(ii)(G).

Item 4.	Ownership
	FPA
(a) Amount beneficially owned: 26,188,451
(b) Percent of class: 5.4
(c) Number of shares to which the person has:


(i)  Sole power to vote or to direct the vote: None
(ii) Shared power to direct the vote: 26,188,451
(iii) Sole power to dispose or to direct the
disposition of: None
(iv) Shared power to dispose or to direct the
disposition of: 26,188,451
	J. Richard Atwood
(a) Amount beneficially owned: 26,188,451
(b) Percent of class: 5.4
(c) Number of shares to which the person has:
(i)  Sole power to vote or to direct the vote: None
(ii) Shared power to direct the vote: 26,188,451
(iii) Sole power to dispose or to direct the
disposition of: None
(iv) Shared power to dispose or to direct the
disposition of: 26,188,451
	Steven T. Romick
(a) Amount beneficially owned: 26,188,451
(b) Percent of class: 5.4
(c) Number of shares to which the person has:
(i)  Sole power to vote or to direct the vote: None
(ii) Shared power to direct the vote: 26,188,451
(iii) Sole power to dispose or to direct the
disposition of: None
(iv) Shared power to dispose or to direct the
disposition of: 26,188,451

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 securities, check the following [ ]

Item 6.	Ownership of More than Five Percent on Behalf of Another
Person.
FPA, in its capacity as investment adviser to its various
clients, may be deemed to be the beneficial owner
of 26,188,451 shares owned by such clients, as in its
capacity as investment adviser it has the power to
dispose, direct the disposition of, and vote the shares
of the issuer owned by its clients.
J. Richard Atwood is a Director of the General Partner.
As a controlling person of FPA, he may be deemed to
beneficially own 26,188,451 shares of the issuer owned by
FPA's clients.
Steven T. Romick is a Director of the General
Partner.  As a controlling person of FPA, he may be
deemed to beneficially own 26,188,451 shares of the
issuer owned by FPA's clients.
Pursuant to Rule 13d-4, J. Richard Atwood and Steven T.
Romick disclaim beneficial ownership of the securities
owned by FPA's clients.

Item 7.	Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on By the Parent
Holding Company or Control Person.
	N/A

Item 8.	Identification and Classification of Members of the
Group.
	N/A


Item 9.	Notice of Dissolution of Group.
	N/A



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 or
with the effect of changing or influencing the control of
the issuer and were not acquired and are not held in
connection with or as a participant in any transaction
having that purpose or effect.

Date:  February 12, 2019


FIRST PACIFIC ADVISORS, LP


By: /s/ J. Richard Atwood
	Name: J. Richard Atwood
	Its: Director of General Partner

_/s/ J. Richard Atwood                   __
J. Richard Atwood


_/s/ Steven T. Romick                    __
Steven T. Romick
?
Exhibit A
Joint Filing Agreement Pursuant to Rule 13d-1
[This agreement is made pursuant to Rule 13d-l(k)(1) under the
Securities and Exchange Act of 1934, as amended (the ?Act?) by
and among the parties listed below, each referenced to herein as
a ?Joint Filer.?  The Joint Filers agree that a statement of
beneficial ownership as required by Sections 13(g) or 13(d) of
the Act and the Rules thereunder may be filed on each of their
behalf on Schedule 13G or Schedule 13D, as appropriate, and that
said joint filing may thereafter be amended by further joint
filings.  The Joint Filers state that they each satisfy the
requirements for making a joint filing under Rule 13d-1.

Date:  February 12, 2019

FIRST PACIFIC ADVISORS, LP


By: /s/ J. Richard Atwood
	Name: J. Richard Atwood
	Its: Director of General Partner

_/s/ J. Richard Atwood                   __
J. Richard Atwood


_/s/ Steven T. Romick                    __
Steven T. Romick


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