Exhibit 1(vv)

                              JANUS INVESTMENT FUND

               CERTIFICATE REDESIGNATING JANUS MID CAP VALUE FUND

     The undersigned, being the Secretary of Janus Investment Fund, a
Massachusetts business trust with transferable shares (the "Trust"), being duly
authorized by a majority of the duly elected and qualified Trustees of the Trust
acting pursuant to Sections 3.6 and 4.1 of the Trust's Amended and Restated
Agreement and Declaration of Trust dated March 18, 2003, as further amended from
time to time (the "Declaration"), does hereby certify that, by affirmative vote
of all Trustees of the Trust present at a meeting of the Trustees, duly called,
convened and held on November 5, 2007, and upon closing of certain conditions as
agreed upon by Janus Capital Management LLC ("Janus Capital") and Perkins
Investment Management LLC ("Perkins"), including receipt of approval by
shareholders of Janus Mid Cap Value Fund (the "Fund") of (i) an Amended and
Restated Investment Advisory Agreement between the Trust, on behalf of the Fund,
and Janus Capital, and (ii) a new Subadvisory Agreement between Janus Capital
and Perkins, with respect to the Fund, such approval of the foregoing obtained
at a meeting of the Fund's shareholders on December 16, 2008, the Fund was
redesignated as Perkins Mid Cap Value Fund, such redesignation to be effective
December 30, 2008.

     All of the current rights and preferences of the Fund remain in full force
and effect, as set forth in the Declaration.

     The undersigned further certifies that she has been duly authorized by the
Trustees of the Trust to take all necessary action to file a copy of this
Certificate with the Secretary of the Commonwealth of Massachusetts and at any
other place required by law or by the Declaration.

     IN WITNESS WHEREOF, I have hereunto set my hand as of the day and year set
forth opposite my signature below.


Dated: December 23, 2008                  /s/ Stephanie Grauerholz-Lofton
                                          --------------------------------------
                                          Stephanie Grauerholz-Lofton, Secretary



                                 ACKNOWLEDGMENT

STATE OF COLORADO             )
                              ) ss.
CITY AND COUNTY OF DENVER     )

     BEFORE ME, the undersigned authority, on this day personally appeared
Stephanie Grauerholz-Lofton, Secretary of Janus Investment Fund, a Massachusetts
business trust, who, after being first duly sworn, stated that she executed the
foregoing document for the consideration therein expressed and in the capacity
therein stated.

     SUBSCRIBED AND SWORN TO this 23rd day of December, 2008

My Commission Expires:


06/08/11                                  /s/ Lynn D. Williams
                                          --------------------------------------
                                          Notary Public

                                          [Notary Seal]