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 *
DEL MATTO ANDREW H
  2. Issuer Name and Ticker or Trading Symbol
FORTINET INC [FTNT]
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)
C/O FORTINET, INC., 899 KIFER ROAD
3. Date of Earliest Transaction (Month/Day/Year)
08/01/2017
(Street)

SUNNYVALE, CA 94086
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 08/01/2017   M(1)   7,500 A $ 0 33,663 D  
Common Stock 08/01/2017   M(2)   1,875 A $ 0 35,538 D  
Common Stock 08/01/2017   M(3)   1,875 A $ 0 37,413 D  
Common Stock 08/01/2017   F(4)   5,872 D $ 36.8 31,541 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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
Restricted Stock Units $ 0 (5) 08/01/2017   M(1)     7,500   (6)   (6) Common Stock 7,500 $ 0 15,000 D  
Restricted Stock Units $ 0 (5) 08/01/2017   M(2)     1,875   (7)   (7) Common Stock 1,875 $ 0 11,250 D  
Restricted Stock Units $ 0 (5) 08/01/2017   M(3)     1,875   (8)   (8) Common Stock 1,875 $ 0 18,750 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
DEL MATTO ANDREW H
C/O FORTINET, INC.
899 KIFER ROAD
SUNNYVALE, CA 94086
      Chief Financial Officer  

Signatures

 /s/ John Whittle, by power of attorney   08/03/2017
**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) Vesting of restricted stock units ("RSUs") granted to the Reporting Person on February 12, 2014.
(2) Vesting of RSUs granted to the Reporting Person on February 11, 2015.
(3) Vesting of RSUs granted to the Reporting Person on February 11, 2016.
(4) Exempt transaction pursuant to Section 16b-3(e) - payment of exercise price or tax liability by delivering or withholding securities incident to the receipt, exercise or vesting of a security issued in accordance with Rule 16b-3. All of the shares reported as disposed of in this Form 4 were relinquished by the Reporting Person and cancelled by the Issuer in exchange for the Issuer's agreement to pay federal and state tax withholding obligations of the Reporting Person resulting from the vesting of RSUs. The Reporting Person did not sell or otherwise dispose of any of the shares reported on this Form 4 for any reason other than to cover required taxes.
(5) Each RSU represents a contingent right to receive one share of the Issuer's common stock.
(6) 25% of the RSUs vested on February 1, 2015, then the remaining 75% of the RSUs vest in equal installments on each quarterly anniversary thereafter, until such time as the RSUs are 100% vested, subject to the continuing employment of the Reporting Person on each vesting date. Shares of the Issuer's common stock will be delivered to the Reporting Person upon vesting.
(7) 25% of the RSUs vest on February 1, 2016, then the remaining 75% of the RSUs vest in equal installments on each quarterly anniversary thereafter, until such time as the RSUs are 100% vested, subject to the continuing employment of the Reporting Person on each vesting date. Shares of the Issuer's common stock will be delivered to the Reporting Person upon vesting.
(8) 25% of the RSUs vest on February 1, 2017, then the remaining 75% of the RSUs vest in equal installments on each quarterly anniversary thereafter, until such time as the RSUs are 100% vested, subject to the continuing employment of the Reporting Person on each vesting date. Shares of the Issuer's common stock will be delivered to the Reporting Person upon vesting.

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