| CUSIP No. | 34959E109 | 
| 1 | NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) | ||||
| Xie Michael | |||||
| 2 | CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
						INSTRUCTIONS) | ||||
| (a) o | |||||
| (b) o | |||||
| 3 | SEC USE ONLY | ||||
| 4 | CITIZENSHIP OR PLACE OF ORGANIZATION | ||||
| United States | |||||
| NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH: | 5 | SOLE VOTING POWER | |||
| 7,374,249 | |||||
| 6 | SHARED VOTING POWER | ||||
| 6,631,000 | |||||
| 7 | SOLE DISPOSITIVE POWER | ||||
| 7,374,249 | |||||
| 8 | SHARED DISPOSITIVE POWER | ||||
| 6,631,000 | |||||
| 9 | AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON | ||||
| 14,005,249 (1) | |||||
| 10 | CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) | ||||
| o | |||||
| 11 | PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) | ||||
| 8.7 (2)% | |||||
| 12 | TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) | ||||
| IN | |||||
| FOOTNOTES | |||||
| (1) Includes (i) 6,748,000 shares of Common Stock held by the Reporting Person; (ii) 2,341,055 shares of Common Stock held by the Michael Xie Grantor Retained Annuity Trust dated February 9, 2011 for which the Reporting Person serves as a trustee; (iii) 2,341,055 shares of Common Stock held by the Danke Wu Grantor Retained Annuity Trust dated February 9, 2011 for which the Reporting Person serves as a trustee; (iv) 1,317,890 shares of Common Stock held by the 2010 K.A. Family Trust dated May 3, 2010 for which the Reporting Person serves as a trustee; (v) 631,000 shares of Common Stock held by The Xie Foundation, a non-profit entity for which the Reporting Person serves as co-president and director; and (vi) 626,249 shares of Common Stock subject to outstanding stock options that are exercisable within 60 days of December 31, 2012.  The Reporting Person has no pecuniary interest in and disclaims beneficial ownership of the shares held by The Xie Foundation. (2) Based on 159,938,847 shares of the Issuer’s Common Stock outstanding as of October 23, 2012, as reported in the Issuer’s Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2012, filed with the Securities and Exchange Commission on October 30, 2012. | |||||
| (a) | Name
												of Issuer | 
| Fortinet, Inc. | 
| (b) | Address
												of Issuer’s Principal Executive Offices | 
| 1090 Kifer Road
 Sunnyvale, CA 94086 | 
| (a) | Name
												of Person Filing | 
| Xie, Michael | 
| (b) | Address
												of Principal Business Office or, if none, Residence | 
| c/o Fortinet, Inc.
 1090 Kifer Road Sunnyvale, CA 94086 | 
| (c) | Citizenship | 
| United States | 
| (d) | Title
												of Class of Securities | 
| Common Stock, $0.001 par value per share | 
| (e) | CUSIP
												Number | 
| 34959E109 | 
| Item
														3. | If
														this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c),
														check whether the person filing is a: | 
| (a) | o | Broker
													or dealer registered under section 15 of the Act (15 U.S.C. 78o). | 
| (b) | o | Bank
													as defined in section 3(a)(6) of the Act (15 U.S.C. 78c). | 
| (c) | o | 
                        Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).
                       | 
| (d) | o | Investment
													company registered under section 8 of the Investment Company Act of 1940 (15
													U.S.C 80a-8). | 
| (e) | o | An
													investment adviser in accordance with §240.13d-1(b)(1)(ii)(E); | 
| (f) | o | An
													employee benefit plan or endowment fund in accordance with
													§240.13d-1(b)(1)(ii)(F); | 
| (g) | o | A
													parent holding company or control person in accordance with §
													240.13d-1(b)(1)(ii)(G); | 
| (h) | o | A
													savings associations as defined in Section 3(b) of the Federal Deposit
													Insurance Act (12 U.S.C. 1813); | 
| (i) | o | A
													church plan that is excluded from the definition of an investment company under
													section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3); | 
| (j) | o | A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). | 
| (k) | o | 
												A group, in accordance with § 240.13d-1(b)(1)(ii)(K). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify
												the type of institution:
												Not applicable. | 
| Item
												4. | Ownership. | 
| (a) | 
									Amount beneficially owned:
									14,005,249 | 
| (b) | 
									Percent of class: 8.7 | 
| (c) | Number
											of shares as to which the person has: | 
| (i) | 
									Sole power to vote or to direct the vote:
									7,374,249 | 
| (ii) | 
									Shared power to vote or to direct the vote:
									6,631,000 | 
| (iii) | 
									Sole power to dispose or to direct the disposition of:
									7,374,249 | 
| (iv) | 
									Shared power to dispose or to direct the disposition of:
									6,631,000 | 
| Item
												5. | Ownership
												of Five Percent or Less of a Class | 
| Item
												6. | Ownership
												of More than Five Percent on Behalf of Another Person. | 
| Item
												7. | Identification
												and Classification of the Subsidiary Which Acquired the Security Being Reported
												on By the Parent Holding Company | 
| Item
												8. | Identification
												and Classification of Members of the Group | 
| Item
												9. | Notice
												of Dissolution of Group | 
| Item
												10.  | Certification | 
| Not applicable. | 
| 
								Date:
								April 29, 2013 | By:
										 | /s/ Michael Xie | |
| Name: Michael Xie | |||
| Title: | |||
| Footnotes: | Item 4(a): The aggregate number of shares beneficially owned includes (i) 6,748,000 shares of Common Stock held by the Reporting Person; (ii) 2,341,055 shares of Common Stock held by the Michael Xie Grantor Retained Annuity Trust dated February 9, 2011 for which the Reporting Person serves as a trustee; (iii) 2,341,055 shares of Common Stock held by the Danke Wu Grantor Retained Annuity Trust dated February 9, 2011 for which the Reporting Person serves as a trustee; (iv) 1,317,890 shares of Common Stock held by the 2010 K.A. Family Trust dated May 3, 2010 for which the Reporting Person serves as a trustee; (v) 631,000 shares of Common Stock held by The Xie Foundation, a non-profit entity for which the Reporting Person serves as co-president and director; and (vi) 626,249 shares of Common Stock subject to outstanding stock options that are exercisable within 60 days of December 31, 2012.  The Reporting Person has no pecuniary interest in and disclaims beneficial ownership of the shares held by The Xie Foundation.
 Item 4(b): The percentage of class is based on 159,938,847 shares of the Issuer’s Common Stock outstanding as of October 23, 2012, as reported in the Issuer’s Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2012, filed with the Securities and Exchange Commission on October 30, 2012. | 
| Attention: | Intentional
										misstatements or omissions of fact constitute Federal criminal violations (See
										18 U.S.C. 1001) |