Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Mantle Ridge LP
  2. Issuer Name and Ticker or Trading Symbol
CSX CORP [CSX]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
900 THIRD AVENUE, 11TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
03/07/2017
(Street)

NEW YORK, NY 10022
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 03/07/2017   X   1,201,138 A $ 30.9 1,204,135 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   1,276,136 A $ 30.85 2,480,271 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,013,062 A $ 30.5 4,493,333 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,377,838 A $ 30.23 6,871,171 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,320,154 A $ 30.79 9,191,325 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,179,655 A $ 31.21 11,370,980 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   211,000 A $ 37.14 11,581,980 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   572,700 A $ 36.95 12,154,680 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   593,285 A $ 31 12,747,965 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   938,626 A $ 31.06 13,686,591 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   208,000 A $ 37.02 13,894,591 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   51,000 A $ 36.82 13,945,591 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   4,000,000 A $ 38.27 17,945,591 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   295,000 A $ 37.22 18,240,591 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,246,491 A $ 30.63 20,487,082 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   1,077,512 A $ 31.3 21,564,594 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   572,000 A $ 36.84 22,136,594 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   483,000 A $ 36.66 22,619,594 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   1,606,731 A $ 30.51 24,226,325 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   1,103,772 A $ 30.59 25,330,097 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   1,592,095 A $ 30.62 26,922,192 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   995,816 A $ 30.66 27,918,008 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   533,726 A $ 30.76 28,451,734 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   190,717 A $ 36.61 28,642,451 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   951,576 A $ 37.38 29,594,027 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   1,074,036 A $ 37.63 30,668,063 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   510,511 A $ 37.56 31,178,574 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   981,688 A $ 37.83 32,160,262 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,791,487 A $ 38.35 34,951,749 I See footnotes (1) (2) (3) (4) (5)
Common Stock 03/07/2017   X   2,488,348 A $ 38.57 37,440,097 I See footnotes (1) (2) (3) (4) (5)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Mantle Ridge LP
900 THIRD AVENUE, 11TH FLOOR
NEW YORK, NY 10022
  X      
MR Argent Advisor LLC
900 THIRD AVENUE, 11TH FLOOR
NEW YORK, NY 10022
  X      
MR Argent GP LLC
900 THIRD AVENUE, 11TH FLOOR
NEW YORK, NY 10022
  X      
Hilal Paul C
900 THIRD AVENUE, 11TH FLOOR
NEW YORK, NY 10022
  X      

Signatures

 MANTLE RIDGE LP, By: Mantle Ridge GP LLC, its managing member, By: PCH MR Advisor Holdings LLC, its managing member, By: /s/ Paul C. Hilal, Paul C. Hilal, Sole Member   03/09/2017
**Signature of Reporting Person Date

 MR ARGENT ADVISOR LLC, By: Mantle Ridge LP, its sole member, By: Mantle Ridge GP LLC, its managing member, By: PCH MR Advisor Holdings LLC, its managing member, By: /s/ Paul C. Hilal,Paul C. Hilal, Sole Member   03/09/2017
**Signature of Reporting Person Date

 MR ARGENT GP LLC, By: MR GP HoldCo LLC, its managing member, By: MR GP HoldCo MM LLC, its managing member, By: PCH MR GP Holdings LLC, its managing member, By: /s/ Paul C. Hilal, Paul C. Hilal, Sole Member   03/09/2017
**Signature of Reporting Person Date

 /s/ Paul C. Hilal, Paul C. Hilal   03/09/2017
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) In addition to Mantle Ridge LP, a Delaware limited partnership ("Mantle Ridge"), this Form 4 is being filed jointly by MR Argent Advisor LLC, a Delaware limited liability company ("MR Argent"), MR Argent GP LLC, a Delaware limited liability company ("Fund GP"), and Paul C. Hilal, a citizen of the United States of America (collectively, the "Reporting Persons"), each of whom has the same business address as Mantle Ridge and may be deemed to have a pecuniary interest in securities reported on this Form 4 (the "Subject Securities"). All Subject Securities reported on this Form 4 are rounded up to the nearest whole share.
(2) Seven shares of the Issuer are held by a wholly owned and wholly controlled special purpose subsidiary of Mantle Ridge.
(3) MR Argent, a wholly owned subsidiary of Mantle Ridge, advises the accounts of MR Argent Fund CE LP, a Delaware limited partnership, and MR Argent Offshore Fund AB LP, MR Argent Offshore Fund BB LP, MR Argent Offshore Fund CB 01 LP, MR Argent Offshore Fund CB 02 LP, MR Argent Offshore Fund CB 03 LP, MR Argent Offshore Fund CB 04 LP, MR Argent Offshore CB 05 LP and MR Argent Offshore CB 07 LP, each a Cayman Islands exempted limited partnership, and, if applicable, their subsidiaries, which are Cayman Islands exempted companies (all such funds and their subsidiaries together, the "Mantle Ridge Funds").
(4) MR Argent, as the investment adviser to the Mantle Ridge Funds, and Mantle Ridge, as the sole member of MR Argent, each may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a 1(a) under the Securities Exchange Act of 1934. As the general partner of the Mantle Ridge Funds, Fund GP may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a). By virtue of Paul C. Hilal's position as ultimately controlling MR Argent, Mantle Ridge and MR GP HoldCo LLC, the sole member of the Fund GP, Paul C. Hilal may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a). Each of the Reporting Persons disclaims any beneficial ownership of any of the Subject Securities, except to the extent of any pecuniary interest therein.
(5) Paul C. Hilal is a member of the board of directors of the Issuer, and as a result, each of the Reporting Persons are directors by deputization for purposes of Section 16 of the Securities Exchange Act of 1934.
 
Remarks:
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