Statement of Ownership (sc 13g)

SCHEDULE 13G

Amendment No. 0
ISHARES Russell 3000 Growth Index ETF
Common Stock
Cusip #464287671

Cusip #464287671

Item 1: Reporting Person - FMR LLC
Item 4: Delaware
Item 5: 507,035
Item 6: 0
Item 7: 507,035
Item 8: 0
Item 9: 507,035
Item 11: 7.456%
Item 12: HC

Cusip #464287671
Item 1: Reporting Person - Edward C. Johnson 3d
Item 4: United States of America
Item 5: 0
Item 6: 0
Item 7: 507,035
Item 8: 0
Item 9: 507,035
Item 11: 7.456%
Item 12: IN

SCHEDULE 13G - TO BE INCLUDED IN

STATEMENTS

FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b)

Item 1(a). Name of Issuer:

ISHARES Russell 3000 Growth Index

ETF

Item 1(b). Name of Issuer's Principal Executive Offices:

400 Howard Street
San Francisco, CA 94105

Item 2(a). Name of Person Filing:

FMR LLC

Item 2(b). Address or Principal Business Office or, if None,
Residence:

82 Devonshire Street, Boston,

Massachusetts 02109

Item 2(c). Citizenship:

Not applicable

Item 2(d). Title of Class of Securities:

Common Stock

Item 2(e). CUSIP Number:

464287671

Item 3. This statement is filed pursuant to Rule 13d-1(b) or 13d-2(b)
and the person filing, FMR LLC, is a parent holding company in accordance with Section 240.13d-1(b)(ii)(G). (Note: See Item 7).

Item 4. Ownership

(a) Amount Beneficially Owned: 507,035 (b) Percent of Class: 7.456% (c) Number of shares as to which such person has: (i) sole power to vote or to direct the vote: 507,035 (ii) shared power to vote or to direct the vote: 0 (iii) sole power to dispose or to

direct the disposition of: 507,035

(iv) shared power to dispose or to direct the disposition of: 0

Item 5. Ownership of Five Percent or Less of a Class.

Not applicable.

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

Various persons have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the Common Stock of ISHARES Russell 3000 Growth Index ETF. No one person's interest in the Common Stock of ISHARES Russell 3000 Growth Index ETF is more than five percent of the total outstanding Common Stock.

Item 7. Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on By the Parent Holding Company.

See attached Exhibit A.

Item 8. Identification and Classification of Members of the Group.

Not applicable. See attached Exhibit A.

Item 9. Notice of Dissolution of Group.

Not applicable.

Item 10. Certification.

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purpose or effect.

Signature

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

February 13, 2013
Date

/s/ Scott C. Goebel Signature Scott C. Goebel Duly authorized under Power of Attorney effective as of June 1, 2008 by and on behalf of FMR LLC and its direct and indirect subsidiaries

SCHEDULE 13G - TO BE INCLUDED IN
STATEMENTS
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b)

Strategic Advisers, Inc., 82 Devonshire Street, Boston, MA 02109, a wholly-owned subsidiary of FMR LLC and an investment adviser registered under Section 203 of the Investment Advisers Act of 1940, provides investment advisory services to individuals. As such, FMR LLC's beneficial ownership includes 507,035 shares, or 7.456%, of the Common Stock outstanding of ISHARES Russell 3000 Growth Index ETF, beneficially owned through Strategic Advisers, Inc.

Members of the family of Edward C. Johnson 3d, Chairman of FMR LLC, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders' voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders' voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC.

SCHEDULE 13G - TO BE INCLUDED IN

STATEMENTS

FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b)
RULE 13d-1(f)(1) AGREEMENT

The undersigned persons, on February 13, 2013, agree and consent to the joint filing on their behalf of this Schedule 13G in connection with their beneficial ownership of the Common Stock of ISHARES Russell 3000 Growth Index ETF at December 31, 2012.

FMR LLC

By /s/ Scott C. Goebel Scott C. Goebel Duly authorized under Power of Attorney effective as of June 1, 2008, by and on behalf of FMR LLC and its direct and indirect subsidiaries

Edward C. Johnson 3d

By /s/ Scott C. Goebel Scott C. Goebel Duly authorized under Power of Attorney effective as of June 1, 2008, by and on behalf of Edward C. Johnson 3d