Sec Form 4 Filing - Spooner Steven Edward @ MITEL NETWORKS CORP - 2018-02-28

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

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1. Name and Address of Reporting Person Spooner Steven Edward 2. Issuer Name and Ticker or Trading Symbol MITEL NETWORKS CORP [ MITL] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chief Financial Officer (Last) (First) (Middle) 350 LEGGET DRIVE, OTTAWA, A6 3. Date of Earliest Transaction (MM/DD/YY) 02/28/2018 (Street) K2K2W7 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 Shares 03/05/2018 M 23,325 A 218,516 D Common Shares 03/05/2018 M 33,750 A 252,266 D Common Shares 03/06/2018 S 26,762 ( 3 ) D $ 8.0086 225,504 D Common Shares 14,900 I Held By Registered Retirement Savings Plan For Steven Edward Spooner Common Shares 5,100 I Held By The Spooner Children Trust ( 4 )

8. Price of Derivative Security (Instr. 5) 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) 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 Restricted Stock Units ( 5 ) 02/28/2018 A 85,575 ( 6 ) ( 5 ) ( 5 ) Common Shares 85,575 ( 5 ) 85,575 D Performance Share Units ( 7 ) 02/28/2018 A 85,575 ( 6 ) ( 8 ) 02/28/2021 Common Shares 85,575 ( 5 ) 85,575 D Restricted Stock Units ( 1 ) 03/05/2018 M 23,325 ( 1 ) ( 1 ) Common Shares 23,325 ( 1 ) 23,325 D Restricted Stock Units ( 2 ) 03/05/2018 M 33,750 ( 2 ) 03/04/2023 Common Shares 33,750 ( 2 ) 67,500 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Spooner Steven Edward 350 LEGGET DRIVE OTTAWA, A6 K2K2W7 Chief Financial Officer Signatures /s/ Steven Edward Spooner 03/07/2018 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Represents 69,975 Common Shares underlying 69,975 RSUs granted to Mr. Spooner on March 5, 2015. These RSUs will vest as follows: (i) 23,325 of the RSUs will vest on March 5, 2017; (ii) 23,325 of the RSUs will vest on March 5, 2018; and (iii) 23,325 of the RSUs will vest on March 5, 2019. ( 2 )Represents 135,000 Common Shares underlying 135,000 Restricted Stock Units ("RSUs") granted to Mr. Spooner on March 4, 2016. These RSUs will vest as follows: (i) 33,750 of the RSUs will vest on March 4, 2017; (ii) 33,750 of the RSUs will vest on March 4, 2018; (iii) 33,750 of the RSUs will vest on March 4, 2019; and (iv) 33,750 of the RSUs will vest on March 4, 2020. ( 3 )Represents the automatic withholding of Common Shares to satisfy tax withholding obligations in connection with the vesting of RSUs. ( 4 )5,100 common shares ("Common Shares") of Mitel Networks Corporation (the "Company") are held by the Spooner Children Trust, of which Mr. Spooner is one of three trustees, for the benefit of the children of Mr. Spooner. Mr. Spooner disclaims beneficial ownership of the Common Shares held for the benefit of his children and this report shall not be deemed an admission that Mr. Spooner is a beneficial owner of such shares for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose. ( 5 )Represents 85,575 Common Shares underlying 85,575 RSUs granted on February 28, 2018. These RSUs vest in four equal installments annually starting February 28, 2019. ( 6 )The late filing of this equity award is due to a clerical error. ( 7 )Date exercisable for PSUs will vary for each vesting tranche based on achievement of share price performance milestones. The PSUs will expire three years from the date of grant. ( 8 )Date exercisable for PSUs will vary for each vesting tranche based on achievement of share price performance milestones. The PSUs will expire three years from the date of grant.

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).

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