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                                  [LETTERHEAD]


                                August 23, 2000

Teltech Resource Network Corporation
2850 Metro Drive
Minneapolis, Minnesota  55425

         Re:      Agreement and Plan of Merger and Reorganization by and among
                  Sopheon plc, Sopheon Corporation, and Teltech Resource Network
                  Corporation dated January 21, 2000, as amended

Ladies and Gentlemen:

         You have requested our opinion as to certain United States federal
income tax consequences of the merger (the "Merger") of Teltech Resource Network
Corporation ("Teltech"), a Minnesota corporation, with and into Sopheon
Corporation ("Merger Sub"), a Minnesota corporation and a wholly-owned
subsidiary of Sopheon plc ("Sopheon"), a United Kingdom public company. The
Merger is being consummated pursuant to the Agreement and Plan of Merger and
Reorganization by and among Teltech, Sopheon, and Merger Sub dated as of January
21, 2000, as amended on April 28, 2000, and July 31, 2000 (the "Merger
Agreement"). Unless otherwise defined, capitalized terms used herein have the
meanings assigned to them in the Merger Agreement.

         In connection with rendering our opinion, we have reviewed the Merger
Agreement, including the Exhibits thereto, the Proxy Statement/Prospectus
constituting part of the Registration Statement on Form F-4 to be filed by
Sopheon with the Securities and Exchange Commission on or about August 24, 2000,
and such other documents and corporate records as we have deemed necessary or
appropriate as a basis therefor. We have assumed that the representations and
warranties contained in the Merger Agreement were true, correct and complete
when made and will continue to be true, correct and complete through the
Effective Time, and that the parties have complied with and, if applicable, will
continue to comply with the covenants contained in the Merger Agreement. We also
have assumed that statements as to factual matters contained in the Proxy
Statement/Prospectus are true, correct, and complete and will continue to be
true, correct, and complete through the Effective Time. Finally, we have relied
on the representations made by Teltech and Sopheon in tax certificates provided
to us dated on or about the date hereof, and we have assumed that such
representations will continue to be true, correct, and complete through the
Effective Time.

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         Based upon the foregoing, in reliance thereon and subject thereto, and
based upon the Internal Revenue Code of 1986, as amended (the "Code"), the
Treasury Regulations promulgated thereunder, judicial decisions, revenue rulings
and revenue procedures of the Internal Revenue Service, and other administrative
pronouncements, all as in effect on the date hereof, and assuming that the
Merger and related transactions will be consummated in accordance with the terms
of the Merger Agreement, it is our opinion that the Merger will qualify as a
reorganization within the meaning of Section 368(a) of the Code. Furthermore, we
hereby confirm that the discussion set forth under the caption "Material Tax
Consequences" in the Proxy Statement/Prospectus, insofar as such discussion
constitutes statements of United States federal income tax law or legal
conclusions, subject to the assumptions, limitations, and qualifications set
forth therein, accurately reflects our opinion of the material United States
federal income tax consequences of the Merger.

         No opinion is expressed as to any matter not specifically addressed
above, including the accuracy of the representations or reasonableness of the
assumptions relied upon by us in rendering the opinion set forth above. Our
opinion is based on current United States federal income tax law and
administrative practice, and we do not undertake to advise you as to any future
changes in United States federal income tax law or administrative practice that
may affect our opinion unless we are specifically retained to do so. We consent
to the use of this opinion as an Exhibit to the Registration Statement on Form
F-4 that includes the Proxy Statement/Prospectus, and to the references to
Fredrikson & Byron, P.A. under the caption "Material Tax Consequences" in the
Proxy Statement/Prospectus.

                                          Very truly yours,

                                          /s/ Fredrikson & Byron, P.A.

                                          FREDRIKSON & BYRON, P.A.