Janus Letterhead ] February 15, 2013 Mr. Douglas Laird Janus Services LLC 151 Detroit Street Denver, Colorado 80206 Dear Mr. Laird:

Exhibit (h)(178)

[ Janus Letterhead ]

February 15, 2013

Mr. Xxxxxxx Xxxxx
Xxxxx Services LLC
000 Xxxxxxx Xxxxxx
Xxxxxx, Xxxxxxxx 00000

Dear Xx. Xxxxx:

Attached is revised Appendix A to the Amended and Restated Transfer Agency Agreement dated June 18, 2002, as may be further amended from time to time (the “Agreement”), between Janus Investment Fund (the “Trust”) and Janus Services LLC (“Janus Services”). The purpose of the revision is to reflect the name changes of Janus Conservative Allocation Fund to Janus Global Allocation Fund — Conservative; Janus Growth Allocation Fund to Janus Global Allocation Fund — Growth; and Janus Moderate Allocation Fund to Janus Global Allocation Fund — Moderate effective February 15, 2013. Pursuant to Section 9 of the Agreement, the Trust hereby requests that Janus Services acknowledge its acceptance of the terms contained in the revised Appendix.

Please indicate your acceptance of the foregoing by executing two copies of this letter, returning one copy to the Trust and retaining one copy for your records.

JANUS INVESTMENT FUND

By:		/s/ Xxxxxxxxx Xxxxxxxxxx-Xxxxxx
Xxxxxxxxx Xxxxxxxxxx- Xxxxxx Vice President, Chief Legal Counsel and Secretary
JANUS SERVICES LLC
By:		/s/ Xxxxxxx Xxxxx
Xxxxxxx Xxxxx
President

Revised effective as of February 15, 2013

APPENDIX A

INTECH Global Dividend Fund
INTECH International Fund
INTECH U.S. Core Fund
INTECH U.S. Growth Fund
INTECH U.S. Value Fund
Janus Asia Equity Fund
Janus Balanced Fund
Janus Contrarian Fund
Janus Diversified Alternatives Fund
Janus Emerging Markets Fund
Janus Enterprise Fund
Janus Flexible Bond Fund
Janus Forty Fund
Janus Fund
Janus Global Allocation Fund — Conservative
Janus Global Allocation Fund — Growth
Janus Global Allocation Fund — Moderate
Janus Global Bond Fund
Janus Global Life Sciences Fund
Janus Global Real Estate Fund
Janus Global Research Fund
Janus Global Select Fund
Janus Global Technology Fund
Janus Government Money Market Fund
Janus Growth and Income Fund
Janus High-Yield Fund
Janus International Equity Fund
Janus Money Market Fund
Janus Overseas Fund
Janus Protected Series — Global
Janus Protected Series — Growth
Janus Real Return Fund
Janus Research Fund
Janus Short-Term Bond Fund
Xxxxx Xxxxxx Fund
Janus Twenty Fund
Janus Venture Fund
Janus World Allocation Fund
Janus Worldwide Fund
Xxxxxxx Global Value Fund
Xxxxxxx Large Cap Value Fund
Xxxxxxx Mid Cap Value Fund
Xxxxxxx Select Value Fund
Xxxxxxx Small Cap Value Fund
Xxxxxxx Value Plus Income Fund