July 30, 2018

Keith Jensen
Chief Financial Officer
FORTINET INC
899 Kifer Road
Sunnyvale, California 94086

       Re: FORTINET INC
           Form 10-Q
           Filed May 8, 2018
           File No. 001-34511

Dear Mr. Jensen:

      We have reviewed your filing and have the following comment. In our
comment, we
may ask you to provide us with information so we may better understand your
disclosure.

       Please respond to this comment within ten business days by providing the
requested
information or advise us as soon as possible when you will respond. If you do
not believe our
comment applies to your facts and circumstances, please tell us why in your
response.

       After reviewing your response to this comment, we may have additional
comments.

Form 10-Q for the quarterly period ended March 31, 2018

Notes to Condensed Consolidated Financial Statements
2. REVENUE RECOGNITION, page 7

1.    We note that you disclose that your sales arrangements contain multiple
distinct
      performance obligations. However, it appears that the FortiGuard security
subscription
      and FortiCare technical support services are bundled with hardware
products and software
      licenses, the FortiOS operating system present in all your FortiGate
appliances are
      updated by the Forticare technical support services, and the FortiGate
hardware and
      software licenses are sold with a broad set of security services enabled
by the FortiGuard
      security subscription. Please explain how your disclosure addresses the
appropriateness
      of not combining these promised goods and services into one performance
obligation. We
      refer you to ASC 606-10-25-19 through 25-21 and ASC 606-10-55-140D
through 606-10-
      55-140F.
 Keith Jensen
FORTINET INC
July 30, 2018
Page 2

        We remind you that the company and its management are responsible for
the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action
or absence of
action by the staff.

        You may contact Amanda Kim, Staff Accountant, at (202)551-3241 or Craig
Wilson, Sr.
Asst. Chief Accountant, at (202)551-3226 if you have questions regarding
comments on the
financial statements and related matters.


FirstName LastNameKeith Jensen
                                                          Division of
Corporation Finance
Comapany NameFORTINET INC
                                                          Office of Information
Technologies
July 30, 2018 Page 2                                      and Services
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