Sec Form 4 Filing - Moore David @ CEMPRA, INC. - 2017-02-23

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 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

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person Moore David 2. Issuer Name and Ticker or Trading Symbol CEMPRA, INC. [ CEMP] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chief Commercial Officer (Last) (First) (Middle) 6320 QUADRANGLE DRIVE, SUITE 360 3. Date of Earliest Transaction (MM/DD/YY) 02/23/2017 (Street) CHAPEL HILL, NC27517 4. If Amendment, Date Original Filed (MM/DD/YY) 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 1,500 D

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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 Employee Stock Option (Right to Buy) $ 3.15 02/23/2017 A 25,000 ( 1 ) 02/22/2027 Common Stock 25,000 $ 0 25,000 D Restricted Stock Units ( 2 ) 02/23/2017 A 25,000 ( 3 ) ( 3 ) Common Stock 25,000 $ 0 25,000 D Employee Stock Option (Right to Buy) $ 23.51 ( 4 ) 12/31/2024 Common Stock 36,363 36,363 D Employee Stock Option (Right to Buy) $ 12.79 ( 5 ) 01/01/2024 Common Stock 100,000 100,000 D Employee Stock Option (Right to Buy) $ 31.13 ( 6 ) 12/31/2025 Common Stock 59,660 59,660 D Employee Stock Option (Right to Buy) $ 3 ( 7 ) 01/02/2027 Common Stock 125,000 125,000 D Restricted Stock Units ( 2 ) ( 3 ) ( 3 ) Common Stock 50,000 50,000 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Moore David 6320 QUADRANGLE DRIVE SUITE 360 CHAPEL HILL, NC27517 Chief Commercial Officer Signatures /s/ Alexander M. Donaldson, by Power of Attorney 02/27/2017 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The option vests according to the following schedule: 1/48th of the shares shall vest at the end of each month over 48 months, beginning after 02/23/2017. ( 2 )Each restricted stock unit represents a contingent right to receive one share of Cempra, Inc. common stock. ( 3 )The restricted stock units vest in full on January 1, 2019, subject to continued employment, or upon termination without cause. ( 4 )The option vests on the following schedule: 1/48th of the shares shall vest at the end of each month over 48th months, beginning after 01/01/2015. ( 5 )The option vests according to the following schedule: 25,000 shares vested immediately on January 2, 2014 and 18,750 shares vest in one year annual installments, beginning January 2, 2015. ( 6 )The option vests on the following schedule: 1/48th of the shares shall vest at the end of each month over 48th months, beginning after January 1, 2016. ( 7 )The option vests according to the following schedule: 1/48th of the shares shall vest at the end of each month over 48 months, beginning after 01/01/2017.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* 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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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 Number.