<PAGE>

                      AMENDMENT NO. 2 TO RIGHTS AGREEMENT


     Amendment No. 2 dated as of May 1, 2000, to the Rights Agreement dated as
of May 1, 1991, as amended by Amendment No 1 to Rights Agreement dated as of
March 27, 2000, and as restated by the Amended and Restated Rights Agreement
dated as of March 27, 2000, by and between Shared Medical Systems Corporation, a
Delaware corporation (the "Company"), and ChaseMellon Shareholder Services,
L.L.C., a New Jersey limited liability company (the successor, pursuant to
Section 19 of such agreement, to the original rights agent) (the "Rights
Agent").

                                   Witnesseth

     WHEREAS, the Company and Pittsburgh National Bank (the original rights
agent) entered into the Rights Agreement, dated as of May 1, 1991 (the "Original
Agreement");

     WHEREAS, the Company and the Rights Agent entered into Amendment No. 1 to
Rights Agreement, dated as of March 27, 2000 ("Amendment No. 1");

     WHEREAS, the Company and the Rights Agent entered into the Amended and
Restated Rights Agreement, dated as of March 27, 2000 (the "Amended and Restated
Agreement"); and

     WHEREAS, the Board of Directors of the Company deems it advisable and in
the best interests of the Company and its stockholders to amend the Original
Agreement, as amended by Amendment No. 1 and as restated by the Amended and
Restated Agreement (as so amended and restated, the "Rights Agreement") in the
manner set forth herein.

     NOW, THEREFORE, in consideration of the premises and the mutual agreements
herein set forth, and intending to be legally bound, the parties hereby agree as
follows:

     Section 1. Amendment to Section 1. Section 1 of the Rights Agreement is
hereby amended to add a new paragraph at the end of such Section to read as
follows:

               "Notwithstanding any other provision of this Agreement, neither
          the execution and delivery of the Agreement and Plan of Merger, by and
          among the Company, Siemens Corporation and Autobahn Acquisition
          Corporation, dated as of April 30, 2000, as the same may be amended
          from time to time, nor the performance thereof in accordance with its
          terms, nor any of the transactions contemplated thereby, shall cause
          Siemens Corporation or Autobahn Acquisition Corporation (or any
          Affiliate or Associate of either of them) to become an Acquiring
          Person or an Adverse Person or cause a Distribution Date or constitute
          or cause a Triggering Event, or otherwise result in the grant of any
          Rights to any person under this Agreement or require any outstanding
          Rights to be exercised, distributed or triggered."
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     Section 2. Amendment to Section 2. The first sentence of Section 2 of the
Rights Agreement is hereby amended to delete the following words:

          "and the holders of the Rights".

     Section 3. Amendment to Section 18(a). Section 18(a) of the Rights
Agreement is hereby amended by adding the following words to the end of such
section:

          "Anything to the contrary notwithstanding, in no event shall the
          Rights Agent be liable for special, punitive, indirect, consequential
          or incidental loss or damage of any kind whatsoever (including but not
          limited to lost profits), even if the Rights Agent has been advised of
          the likelihood of such loss or damage."

     Section 4. Agreement in Effect. Except as hereby amended, the Rights
Agreement shall remain in full force and effect.

     Section 5. Governing Law. This Amendment shall be deemed to be a contract
made under the laws of the jurisdiction of incorporation of the Company, as the
same may change from time to time, and for all purposes shall be governed by and
construed in accordance with the laws of such jurisdiction applicable to
contracts made and to be performed entirely within such jurisdiction.

     Section 6. Counterparts. This Amendment may be executed in any number of
counterparts, and each of such counterparts shall, for all purposes, be deemed
to be an original, and all such counterparts shall together constitute but one
and the same instrument.

     Section 7. Descriptive Headings. The descriptive headings of the Sections
of this Amendment No. 2 are inserted for convenience only and shall not control
or affect the meaning or construction of any of the provisions hereof.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed by their duly authorized officers as of the day and year first
above written.


Attest:                                  SHARED MEDICAL SYSTEMS CORPORATION


By /s/ Bonnie L. Shuman                  By /s/ Terrence W. Kyle
  -----------------------                  -----------------------
  Name:  Bonnie L. Shuman                  Name:  Terrence W. Kyle
  Title: Vice President,                   Title: Senior Vice President,
         General Counsel                          Chief Financial Officer,
         and Assistant                            Treasurer and Assistant
         Secretary                                Secretary

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Attest:                                  CHASEMELLON SHAREHOLDER SERVICES L.L.C.

By /s/ Donald Messmer                    By /s/ Robert Kavanagh
  -----------------------                  -----------------------
  Name:  Donald Messmer                    Name:  Robert Kavanagh
  Title: Assistant Vice President          Title: Vice President


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