<PAGE>   1


                                                                   EXHIBIT 10.20




                     FIRST AMENDMENT TO EMPLOYMENT AGREEMENT




         THIS FIRST AMENDMENT TO EMPLOYMENT AGREEMENT ("Amendment") is entered
into on May 15, 2000 (the "Effective Time"), by and between Scott D. Porter, an
individual resident of the State of Iowa ("Executive"), and Stockpoint, Inc., a
Delaware corporation ("Company"), and is an amendment to the Employment
Agreement ("Agreement") between the parties hereto dated March 1, 2000.



         WHEREAS, Executive has heretofore been employed as the Chief Financial
Officer of the Company; and



         WHEREAS, the Company desires to continue to have the benefit of the
Executive's services as a corporate officer of the Company;



         NOW, THEREFORE, in consideration of the premises, the respective
undertakings of the Company and Executive set forth below, the Company and
Executive agree as follows:



         1.   That the provisions of Section 4.01 of the Agreement be stricken
and in lieu thereof the following inserted:



              "4.01 Base Salary. As base compensation for all services to be
         rendered by Executive under this Agreement during the first year of the
         term of this Agreement, the Company shall pay to Executive a base
         salary at a rate of $105,000 per year, which salary shall be paid on a
         twice-monthly basis in accordance with the Company's normal payroll
         procedures and policies. Beginning May 15, 2000, the base salary shall
         be at a rate of $135,000 per year. The salary payable to Executive
         during each subsequent year during the term of this Agreement shall be
         established by the Company and Executive, but in no event shall the
         salary for any subsequent year be less than the base salary in effect
         for the prior year."



         2.   That the provisions of Section 8.04 of the Agreement be stricken
and in lieu thereof the following inserted:



              "8.04 Wage and Benefit Continuation. If Executive's employment by
         the Company is terminated pursuant to subsection 8.01 (d) or 8.01(e),
         the Company shall continue to pay to Executive his/her base salary and
         shall continue to provide health insurance benefits for Executive for a
         period 9 months after termination. In the event of a "Change in
         Control" as defined in Section 4.07, if Executive's employment is
         terminated by "Constructive Termination" as defined in Section 8.01(2)
         or without "Cause" as defined in as defined in Section 8.01(1) within
         12 months after the effective date of a "Change in Control," the
         severance compensation package defined in this Section will be doubled
         to 18 months. Notwithstanding anything else in this Section 8.04,
         Executive shall not be entitled under this Section 8.04 or any other
         provision of this Agreement to receive any cash compensation pursuant
         to this Agreement which constitutes an "excess parachute payment"
         within the meaning of Section 280G of the Internal Revenue Code of
         1986, as amended, or any successor provision or regulations
         promulgated.



         If this Agreement is terminated pursuant to subsection 8.01 (a), 8.01
         (c), or 8.01 (f). Executive's right to base salary and benefits shall
         immediately terminate except as may otherwise be required by applicable
         law.




                   If Executive's employment is terminated by the Company
         pursuant to subsection 8.01(a), 8.01(b), 8.01(d) or 8.01(e). Executive
         shall also be entitled to receive any bonus payment that as of the time
         of termination would have been payable to him/her pursuant to any
         incentive plan then in effect. "




         3.   The rest and remainder of said Agreement shall remain in full
force and effect, except as otherwise amended.



         IN WITNESS WHEREOF, Executive and the Company have executed this
Agreement as of date set forth herein.




                                     Stockpoint, Inc.




                                     By: /s/ W.B.Staib
                                        ------------------------



                                     Its CEO
                                        ------------------------




                                     EXECUTIVE



                                     /s/ Scott D. Porter
                                     ---------------------------
                                     Scott D. Porter