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 *
Welling Glenn W.
   2. Issuer Name and Ticker or Trading Symbol
MEDIFAST INC [MED] 		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)
C/O ENGAGED CAPITAL, LLC, 610 NEWPORT CENTER DR. SUITE 250		 3. Date of Earliest Transaction (Month/Day/Year)
12/01/2017
(Street)

NEWPORT BEACH, CA 92660		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ 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 12/01/2017   S   251,950 D $ 64.6 242,169 I By: Engaged Capital Flagship Master Fund, LP (1)
Common Stock 12/01/2017   S   23,050 D $ 64.6 22,380 I By: Managed Account of Engaged Capital, LLC (2)
Common Stock               5,309 D  

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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
Welling Glenn W.
C/O ENGAGED CAPITAL, LLC
610 NEWPORT CENTER DR. SUITE 250
NEWPORT BEACH, CA 92660		   X      

Signatures

 /s/ Glenn W. Welling   12/05/2017
**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) Securities owned directly by Engaged Capital Flagship Master Fund, LP ("Engaged Capital Master"). Mr. Welling, solely by virtue of his position as the Founder and Chief Investment Officer of Engaged Capital, LLC ("Engaged Capital"), the general partner and investment adviser of Engaged Capital Master, and as the sole member of Engaged Capital Holdings, LLC ("Engaged Holdings"), the managing member of Engaged Capital, may be deemed to beneficially own the securities owned directly by Engaged Capital Master for purposes of Section 16. Mr. Welling expressly disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.
(2) Securities held in an account separately managed by Engaged Capital (the "Engaged Capital Account"). Mr. Welling, solely by virtue of his position as the Founder and Chief Investment Officer of Engaged Capital, the investment adviser of the Engaged Capital Account, and as the sole member of Engaged Holdings, the managing member of Engaged Capital, may be deemed to beneficially own the securities held in the Engaged Capital Account for purposes of Section 16. Mr. Welling expressly disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.

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