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                                    EXHIBIT 5

                               FREDRIKSON & BYRON, P.A.
                       900 Second Avenue South, Suite 1100
                          Minneapolis, Minnesota 55402

                            Telephone: (612) 347-7000
                            Facsimile: (612) 347-7077


                               September 28, 2001


CorVu Corporation
3400 West 66th Street
Edina, Minnesota  55435

         Re:  REGISTRATION STATEMENT ON FORM S-8

Ladies/Gentlemen:

         We are acting as corporate counsel to CorVu Corporation (the "Company")
in connection with the original registration by the Company on Form S-8 (the
"Registration Statement") under the Securities Act of 1933, as amended (the
"Act") of options and an aggregate of 500,000 shares (the "Shares") of Common
Stock issuable pursuant to the Company's 2001 Employee Stock Purchase Plan (the
"Plan").

         In acting as such counsel and for the purpose of rendering this
opinion, we have reviewed copies of the following, as presented to us by the
Company:

         1.       The Company's Articles of Incorporation, as amended.

         2.       The Company's Bylaws, as amended.

         3.       Certain corporate resolutions adopted by the Board of
                  Directors of the Company pertaining to the adoption of the
                  Plan.

         4.       The Plan.

         5.       The Registration Statement.

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         Based on, and subject to, the foregoing and upon representations and
information provided by the Company or its officers or directors, it is our
opinion as of this date that:

         1.       The Shares are validly authorized by the Company's Articles
                  of Incorporation, as amended.

         2.       Upon issuance and delivery of the Shares against receipt by
                  the Company of the consideration for the Shares pursuant to
                  the terms of the Plan, the Shares will be validly issued,
                  fully paid and nonassessable.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.

                                                 Very truly yours,

                                                 FREDRIKSON & BYRON, P.A.



                                                 By    /s/ John H. Stout
                                                   --------------------------
                                                     John H. Stout


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