SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                ________________

                                 Schedule 13G/A
                                ________________

    INFORMATION TO BE INCLUDED IN STATEMENTS PURSUANT TO RULES 13d-1(b),(c)
              AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2
                 UNDER THE SECURITIES EXCHANGE ACT OF 1934*

                                (Amendment No. 1)

                                 Illumina, Inc.
                                (Name of Issuer)

	                          Common Stock
                         (Title of Class of Securities)

                                   452327109
                                 (CUSIP Number)

                                January 2, 2015
            (Date of Event Which Requires Filing of this Statement)


     Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
     [ ]    Rule 13d-1(b)
     [X]    Rule 13d-1(c)
     [ ]    Rule 13d-1(d)

___________

     *  The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.


     The information required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to all other provisions of the Act
(however, see the Notes).



Schedule 13G/A                                                  PAGE 2 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Global Investors LP
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    8,189,589
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    8,189,589
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          8,189,589
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          5.8%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          PN
_____________________________________________________________________________



Schedule 13G/A                                                  PAGE 3 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Global Performance LLC
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    5,478,198
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    5,478,198
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          5,478,198
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          3.9%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          OO
_____________________________________________________________________________



Schedule 13G/A                                              PAGE 4 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Global Equities LP
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,868,070
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    1,868,070
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          1,868,070
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          1.3%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          PN
_____________________________________________________________________________



Schedule 13G/A                                                 PAGE 5 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Global Equities II LP
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    109,565
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    109,565
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          109,565
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          0.1%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          PN
_____________________________________________________________________________



Schedule 13G/A                                               PAGE 6 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          VGE III Portfolio Ltd.
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Cayman Islands
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    3,500,563
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    3,500,563
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          3,500,563
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          2.5%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          CO
_____________________________________________________________________________



Schedule 13G/A                                                  PAGE 7 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Long Fund GP LLC
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    2,245,691
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    2,245,691
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          2,245,691
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          1.6%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          OO
_____________________________________________________________________________



Schedule 13G/A                                                  PAGE 8 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Long Fund Master Ltd.
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Cayman Islands
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    2,245,691
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    2,245,691
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          2,245,691
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          1.6%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          CO
_____________________________________________________________________________



Schedule 13G/A                                                  PAGE 9 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Viking Global Opportunities GP LLC
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    465,700
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    465,700
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          465,700
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          0.3%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          OO
_____________________________________________________________________________



Schedule 13G/A                                                  PAGE 10 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          VGO Portfolio GP LLC
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Delaware
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    465,700
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    465,700
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          465,700
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          0.3%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          OO
_____________________________________________________________________________



Schedule 13G/A                                                  PAGE 11 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          VGO Liquid Portfolio Sub-Master LP
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Cayman Islands
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    465,700
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    465,700
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          465,700
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          0.3%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          PN
_____________________________________________________________________________



Schedule 13G/A                                                 PAGE 12 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          O. Andreas Halvorsen
_____________________________________________________________________________
     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________
     (3)  SEC USE ONLY

_____________________________________________________________________________
     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          Norway
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    8,189,589
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    8,189,589
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          8,189,589
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          5.8%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          IN
_____________________________________________________________________________



Schedule 13G/A                                                 PAGE 13 of 21

CUSIP No. 452327109
_____________________________________________________________________________

     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          David C. Ott
_____________________________________________________________________________

     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________

     (3)  SEC USE ONLY
_____________________________________________________________________________

     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          United States
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    8,189,589
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    8,189,589
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          8,189,589
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          5.8%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          IN
_____________________________________________________________________________



Schedule 13G/A                                                PAGE 14 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Thomas W. Purcell, Jr.
_____________________________________________________________________________

     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________

     (3)  SEC USE ONLY
_____________________________________________________________________________

     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          United States
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    8,189,589
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    8,189,589
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          8,189,589
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          5.8%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          IN
_____________________________________________________________________________



Schedule 13G/A                                                PAGE 15 of 21

CUSIP No. 452327109
_____________________________________________________________________________
     (1)  NAME OF REPORTING PERSON
          S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
          Daniel S. Sundheim
_____________________________________________________________________________

     (2)  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                    (a)  [ ]
                                                                    (b)  [x]
_____________________________________________________________________________

     (3)  SEC USE ONLY
_____________________________________________________________________________

     (4)  CITIZENSHIP OR PLACE OF ORGANIZATION
          United States
_____________________________________________________________________________

NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         ______________________________________________________________

BENEFICIALLY   (6)  SHARED VOTING POWER
                    8,189,589
OWNED BY       ______________________________________________________________

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      ______________________________________________________________

PERSON WITH    (8)  SHARED DISPOSITIVE POWER
                    8,189,589
_____________________________________________________________________________
     (9)  AGGREGATE AMOUNT BENEFICIALLY OWNED
          BY EACH REPORTING PERSON
          8,189,589
_____________________________________________________________________________
    (10)  CHECK BOX IF THE AGGREGATE AMOUNT
          IN ROW (9) EXCLUDES CERTAIN SHARES                             [ ]
_____________________________________________________________________________
    (11)  PERCENT OF CLASS REPRESENTED
          BY AMOUNT IN ROW (9)
          5.8%
_____________________________________________________________________________
    (12)  TYPE OF REPORTING PERSON
          IN
_____________________________________________________________________________



Schedule 13G/A                                                 PAGE 16 of 21

CUSIP No. 452327109

ITEM 1(a).  NAME OF ISSUER:
            Illumina, Inc.

ITEM 1(b).  ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
            5200 Illumina Way
            San Diego, California  92122

ITEM 2(a).  NAME OF PERSON FILING:
	    Viking Global Investors LP ("VGI"),
	    Viking Global Performance LLC ("VGP"),
	    Viking Global Equities LP ("VGE"),
	    Viking Global Equities II LP ("VGEII"),
	    VGE III Portfolio Ltd. ("VGEIII"),
            Viking Long Fund GP LLC ("VLFGP"),
	    Viking Long Fund Master Ltd. ("VLFM"),
	    Viking Global Opportunities GP LLC ("VGOGP"),
	    VGO Portfolio GP LLC ("VGOP"),
	    VGO Liquid Portfolio Sub-Master LP ("VGOLP"),
	    O. Andreas Halvorsen, David C. Ott, Thomas W. Purcell, Jr. and
	    Daniel S. Sundheim (collectively, the "Reporting Persons")

ITEM 2(b).  ADDRESS OF PRINCIPAL OFFICE OR, IF NONE, RESIDENCE:
            The business address of each of the Reporting Persons is
            55 Railroad Avenue, Greenwich, Connecticut  06830.

ITEM 2(c).  CITIZENSHIP:
            VGI, VGE and VGEII are Delaware limited partnerships;
            VGEIII and VLFM are Cayman Islands exempted companies;
            VGP, VLFGP, VGOGP and VGOP are Delaware limited liability
            companies; and VGOLP is a Cayman Islands exempted limited
	    partnership. O. Andreas Halvorsen is a citizen of Norway.
            David C. Ott, Thomas W. Purcell, Jr. and Daniel S. Sundheim
	    are citizens of the United States.

ITEM 2(d).  TITLE OF CLASS OF SECURITIES:
            Common Stock ("Common Stock")

ITEM 2(e).  CUSIP NUMBER:  452327109

ITEM 3.     IF THIS STATEMENT IS FILED PURSUANT TO 13d-1(b) OR 13d-2(b) OR (c),
            CHECK WHETHER THE PERSON FILING IS A:

          (a) [ ]   Broker or dealer registered under Section 15 of the
                    Act

          (b) [ ]   Bank as defined in Section 3(a)(6) of the Act

          (c) [ ]   Insurance Company as defined in Section 3(a)(19) of
                    the Act

          (d) [ ]   Investment Company registered under Section 8 of the
                    Investment Company Act of 1940

          (e) [ ]   Investment Adviser registered under Section 203 of the
                    Investment Advisers Act of 1940: see Rule 13d-
                    1(b)(1)(ii)(E)

          (f) [ ]   Employee Benefit Plan, Pension Fund which is subject
                    to the provisions of the Employee Retirement Income
                    Security Act of 1974 or Endowment Fund; see Rule 13d-
                    1(b)(1)(ii)(F)



Schedule 13G/A                                              PAGE 17 of 21

CUSIP No. 452327109

          (g) [ ]   Parent Holding Company, in accordance with Rule 13d-
                    1(b)(ii)(G)

          (h) [ ]   Savings Associations as defined in Section 3(b) of the
                    Federal Deposit Insurance Act

          (i) [ ]   Church Plan that is excluded from the definition of an
                    investment company under Section 3(c)(14) of the
                    Investment Company Act of 1940

          (j) [ ]   A non-U.S. institution in accordance with
		    Rule 240.13d-1(b)(1)(ii)(J)

	  (k) [ ]   Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
                    If filing as a non-U.S. institution in accordance with
                    Rule 240.13d-1(b)(1)(ii)(J), please specify
		    the type of institution:

ITEM 4.   OWNERSHIP.

     A.  VGI
          (a)  Amount beneficially owned: 8,189,589
          (b)  Percent of class: 5.8%
	       The percentages used herein and in this Item 4 are calculated based
	       upon the Company's Form 10-Q for the quarterly period ended
	       September 28, 2014 filed on October 29, 2014, which states that as of
	       October 8, 2014 there were 142,000,000 shares of Common Stock
	       outstanding.
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         8,189,589
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 8,189,589

                  VGI provides managerial services to VGE, VGEII, VGEIII, VLFM
	          and VGOLP. VGI has the authority to dispose of and vote
 		  the shares of Common Stock.

	          Based on Rule 13d-3 of the Securities Exchange Act of 1934,
	          as amended (the "Act"), VGI may be deemed to beneficially
	          own the shares of Common Stock directly held by VGE, VGEII,
	          VGEIII, VLFM and VGOLP. VGI does not directly own any shares
		  of Common Stock.



Schedule 13G/A                                               PAGE 18 of 21

CUSIP No. 452327109

     B.  VGP
          (a)  Amount beneficially owned: 5,478,198
          (b)  Percent of class: 3.9%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         5,478,198
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 5,478,198

		  VGP, as the general partner of VGE and VGEII, has the
		  authority to dispose of and vote the shares of Common Stock
	          directly owned by VGE and VGEII.  VGP serves as investment
		  manager to VGEIII and has the authority to dispose of and vote
		  the shares of Common Stock directly owned by VGEIII.  VGP does
		  not directly own any shares of Common Stock.

	          Based on Rule 13d-3 of the Act, VGP may be deemed to
	          beneficially own the shares of Common Stock directly held by
		  VGE, VGEII and VGEIII.

     C.  VLFGP
          (a)  Amount beneficially owned: 2,245,691
          (b)  Percent of class: 1.6%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         2,245,691
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 2,245,691

                  VLFGP serves as the investment manager of VLFM and has the
		  authority to dispose of and vote the shares of Common Stock
	          directly owned by VLFM.  VLFGP does not directly own
		  any shares of Common Stock.

                  Based on Rule 13d-3 of the Act, VLFGP may be deemed to
	          beneficially own the shares of Common Stock directly held by
		  VLFM.

     D.  VGOGP
          (a)  Amount beneficially owned: 465,700
          (b)  Percent of class: 0.3%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         465,700
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 465,700

                  VGOGP serves as the sole member of VGOP and has the
		  authority to dispose of and vote the shares of Common Stock
		  controlled by VGOP, which consists of the shares of
		  Common Stock directly held by VGOLP. VGOGP does not directly own
		  any shares of Common Stock.

                  Based on Rule 13d-3 of the Act, VGOGP may be deemed to
	          beneficially own the shares of Common Stock controlled by VGOP,
		  which consists of the shares of Common Stock directly held by
		  VGOLP.

     E.  VGOP
          (a)  Amount beneficially owned: 465,700
          (b)  Percent of class: 0.3%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         465,700
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 465,700

                  VGOP serves as the general partner of VGOLP and has the
		  authority to dispose of and vote the shares of Common Stock
	          directly owned by VGOLP.  VGOP does not directly own
		  any shares of Common Stock.

                  Based on Rule 13d-3 of the Act, VGOP may be deemed to
	          beneficially own the shares of Common Stock directly held by
		  VGOLP.



Schedule 13G/A                                               PAGE 19 of 21

CUSIP No. 452327109

      F.  VGE
          (a)  Amount beneficially owned: 1,868,070
          (b)  Percent of class: 1.3%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         1,868,070
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 1,868,070

                   VGE has the authority to dispose of and vote the shares
		   of Common Stock directly owned by it, which power may be
		   exercised by its general partner, VGP, and by VGI, an
		   affiliate of VGP, which provides managerial services to VGE.

      G.  VGEII
          (a)  Amount beneficially owned: 109,565
          (b)  Percent of class: 0.1%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         109,565
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 109,565

                   VGEII has the authority to dispose of and vote the shares
		   of Common Stock directly owned by it, which power may be
		   exercised by its general partner, VGP, and by VGI, an
		   affiliate of VGP, which provides managerial services to VGEII.

      H.  VGEIII
          (a)  Amount beneficially owned: 3,500,563
          (b)  Percent of class: 2.5%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         3,500,563
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 3,500,563

                   VGEIII has the authority to dispose of and vote the shares
		   of Common Stock directly owned by it, which power may be
		   exercised by its investment manager, VGP, and by VGI, an
		   affiliate of VGP, which provides managerial services to VGEIII.
		   Viking Global Equities III Ltd. (a Cayman Islands exempted
		   company) invests substantially all of its assets through VGEIII.

      I.  VLFM
          (a)  Amount beneficially owned: 2,245,691
          (b)  Percent of class: 1.6%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         2,245,691
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 2,245,691

                   VLFM has the authority to dispose of and vote the
		   shares of Common Stock directly owned by it, which power may
		   be exercised by its investment manager, VLFGP, and by VGI,
		   an affiliate of VLFGP, which provides managerial services
                   to VLFM. Viking Long Fund LP (a Delaware limited partnership)
		   and Viking Long Fund III Ltd. (a Cayman Islands exempted
		   company), through its investment in Viking Long Fund Intermediate
		   LP (a Cayman Islands limited partnership), invest substantially
		   all of their assets through VLFM.

      J.  VGOLP
          (a)  Amount beneficially owned: 465,700
          (b)  Percent of class: 0.3%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         465,700
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 465,700

                   VGOLP has the authority to dispose of and vote the
		   shares of Common Stock directly owned by it, which power may
		   be exercised by its general partner, VGOP, and by VGI,
		   an affiliate of VGOP, which provides managerial services
                   to VGOLP. Viking Global Opportunities LP (a Delaware limited
		   partnership) and Viking Global Opportunities III LP (a Cayman
		   Islands exempted limited partnership), through its investment
		   in Viking Global Opportunities Intermediate LP (a Cayman Islands
		   exempted limited partnership), invest substantially all of their
		   assets in Viking Global Opportunities Master LP (a Cayman Islands
		   exempted limited partnership), which in turn invests through VGOLP.



Schedule 13G/A                                               PAGE 20 of 21

CUSIP No. 452327109

       K.  O. Andreas Halvorsen, David C. Ott, Thomas W. Purcell, Jr. and
	   Daniel S. Sundheim
          (a)  Amount beneficially owned: 8,189,589
          (b)  Percent of class: 5.8%
          (c)  Number of shares as to which such person has:
                  (i)    sole power to vote or to direct the vote
                         0
                  (ii)   shared power to vote or to direct the vote
                         8,189,589
                  (iii)  sole power to dispose or to direct the disposition
                         of 0
                  (iv)   shared power to dispose or to direct the disposition
                         of 8,189,589

	          Messrs. Halvorsen, Ott, Purcell and Sundheim, as
	          Executive Committee Members of VGI, VGP, VLFGP and VGOGP,
		  have shared authority to dispose of and vote the shares of
		  Common Stock beneficially owned by VGI, VGP, VLFGP and VGOGP.
		  None of Messrs. Halvorsen, Ott, Purcell and Sundheim directly
		  owns any shares of Common Stock.

	          Based on Rule 13d-3 of the Act, each may be deemed to beneficially
	          own the shares of Common Stock directly held by VGE, VGE II,
		  VGEIII, VLFM and VGOLP.

ITEM 5.   OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
          If this statement is being filed to report the fact that as of the
          date hereof the Reporting Persons has ceased to be the beneficial
          owner of more than five percent of the class of securities,
          check the following.[]

ITEM 6.   OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.
          Yes, see Item 4.

ITEM 7.   IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
          THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.
	  Not applicable.

ITEM 8.   IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
	  Not applicable.

ITEM 9.   NOTICE OF DISSOLUTION OF GROUP.
	  Not applicable.

ITEM 10.  CERTIFICATION.  (if filing pursuant to Rule 13d-1(c))
          By signing below each Reporting Person certifies that, to the best
          of its knowledge and belief, the securities referred to above were not
          acquired and are not held for the purpose of or with the effect of
          changing or influencing the control of the issuer of the securities
          and were not acquired and not held in connection with or as a
          participant in any transaction having that purpose or effect.



Schedule 13G/A                                             PAGE 21 of 21

CUSIP No. 452327109

SIGNATURES

      After reasonable inquiry and to the best of our knowledge and belief,
the undersigned certify that the information set forth in this statement is
true, complete and correct.

DATED: January 6, 2015
			/s/ O. ANDREAS HALVORSEN
                        By: O. Andreas Halvorsen - individually and
                        as an Executive Committee Member of
                        VIKING GLOBAL PERFORMANCE LLC, on behalf
                        of itself and VIKING GLOBAL EQUITIES LP,
                        VIKING GLOBAL EQUITIES II LP and VGE III PORTFOLIO LTD.,
                        and as an Executive Committee Member of
                        Viking Global Partners LLC, on behalf of
                        VIKING GLOBAL INVESTORS LP, and as
			an Executive Committee Member of
			VIKING LONG FUND GP LLC, on behalf of itself
                        and VIKING LONG FUND MASTER LTD., and as
			an Executive Committee Member of
			VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf
			of itself and VGO PORTFOLIO GP LLC and
			VGO LIQUID PORTFOLIO SUB-MASTER LP

                        /s/ DAVID C. OTT
                        By: David C. Ott - individually and
                        as an Executive Committee Member of
                        VIKING GLOBAL PERFORMANCE LLC, on behalf
                        of itself and VIKING GLOBAL EQUITIES LP,
                        VIKING GLOBAL EQUITIES II LP and VGE III PORTFOLIO LTD.,
                        and as an Executive Committee Member of
                        Viking Global Partners LLC, on behalf of
                        VIKING GLOBAL INVESTORS LP, and as
			an Executive Committee Member of
			VIKING LONG FUND GP LLC, on behalf of itself
                        and VIKING LONG FUND MASTER LTD., and as
			an Executive Committee Member of
			VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf
			of itself and VGO PORTFOLIO GP LLC and
			VGO LIQUID PORTFOLIO SUB-MASTER LP

                        /s/ THOMAS W. PURCELL, JR.
                        By: Thomas W. Purcell, Jr. - individually and
                        as an Executive Committee Member of
                        VIKING GLOBAL PERFORMANCE LLC, on behalf
                        of itself and VIKING GLOBAL EQUITIES LP,
                        VIKING GLOBAL EQUITIES II LP and VGE III PORTFOLIO LTD.,
                        and as an Executive Committee Member of
                        Viking Global Partners LLC, on behalf of
                        VIKING GLOBAL INVESTORS LP, and as
			an Executive Committee Member of
			VIKING LONG FUND GP LLC, on behalf of itself
                        and VIKING LONG FUND MASTER LTD., and as
			an Executive Committee Member of
			VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf
			of itself and VGO PORTFOLIO GP LLC and
			VGO LIQUID PORTFOLIO SUB-MASTER LP

                        /s/ DANIEL S. SUNDHEIM
                        By: Daniel S. Sundheim - individually and
                        as an Executive Committee Member of
                        VIKING GLOBAL PERFORMANCE LLC, on behalf
                        of itself and VIKING GLOBAL EQUITIES LP,
                        VIKING GLOBAL EQUITIES II LP and VGE III PORTFOLIO LTD.,
                        and as an Executive Committee Member of
                        Viking Global Partners LLC, on behalf of
                        VIKING GLOBAL INVESTORS LP, and as
			an Executive Committee Member of
			VIKING LONG FUND GP LLC, on behalf of itself
                        and VIKING LONG FUND MASTER LTD., and as
			an Executive Committee Member of
			VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf
			of itself and VGO PORTFOLIO GP LLC and
			VGO LIQUID PORTFOLIO SUB-MASTER LP