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                                                                     Exhibit 4.1


                                MANOR CARE, INC.
                             THIRD RIGHTS AMENDMENT
                             ----------------------


         THIRD AMENDMENT, dated as of March 11, 2000 (this "Amendment"), to the
Rights Agreement, dated as of May 2, 1995, as amended, (the "Rights Agreement"),
between MANOR CARE, INC., as successor to HEALTH CARE AND RETIREMENT
CORPORATION, a Delaware corporation (the "Company"), and HARRIS TRUST AND
SAVINGS BANK (the "Rights Agent").

         The Company and the Rights Agent have heretofore executed and entered
into the Rights Agreement. Pursuant to Section 26 of the Rights Agreement, the
Company and the Rights Agent may from time to time supplement or amend the
Rights Agreement in accordance with the provisions of Section 26 thereof. All
acts and things necessary to make this Amendment a valid agreement according to
its terms have been done and performed, and the execution and delivery of this
Agreement by the Company and the Rights Agent have been in all respects
authorized by the Company and the Rights Agent.

         In consideration of the foregoing premises and mutual agreements set
forth in the Rights Agreement and this Amendment, the parties hereto agree as
follows:

         1. The definition of "Acquiring Person" set forth in Section 1.1 of the
Rights Agreement is hereby modified by and amended by adding the following
sentence at the end thereof:

                  Notwithstanding the foregoing, none of (i) Stewart Bainum,
                  Jr., (ii) any other Person or group approved by the Board of
                  Directors or the Special Committee of the Board of Directors
                  of the Company (any of Stewart Bainum, Jr. and each such other
                  Person or group being an "Approved Person") and (iii) each
                  other stockholder of the Company with whom an Approved Person
                  may from time to time be deemed to have formed a group shall
                  become an Acquiring Person solely as a result of Permitted
                  Actions (as such term is hereinafter defined) taken on or
                  after March 10, 2000 and prior to the Company's announcement
                  of either an Extraordinary Transaction (as hereinafter
                  defined) with a Person other than the Approved Person or that
                  the Company is no longer exploring the possibility of an
                  Extraordinary Transaction (the "Termination Time"). "Permitted
                  Action" means having non-public discussions with stockholders
                  of the Company solely to inquire whether they would be
                  interested in becoming participants


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                  in the submission by an Approved Person of a proposal for a
                  negotiated acquisition of the Company pursuant to an
                  invitation from the Special Committee of the Company's Board
                  of Directors (and provided no information is disclosed to such
                  stockholders in violation of any agreement between the
                  Approved Person and the Company) or entering into any
                  arrangements, agreements or understandings with such
                  stockholders solely regarding such participation, provided
                  that all parties (including the Approved Person) party to such
                  agreements, arrangements or understandings do not in the
                  aggregate beneficially own more than 35% of the then
                  outstanding Common Shares of the Company and any such
                  arrangement, agreement or understanding must, by its terms,
                  automatically terminate at the Termination Time.
                  "Extraordinary Transaction" shall occur if the Board of
                  Directors of the Company approves a transaction (or a binding
                  agreement relating thereto) with any person or group that
                  would result in such person or group beneficially owning more
                  than 35% of the outstanding voting securities of the Company
                  (or a successor to the Company in a merger or consolidation
                  transaction) or all or substantially all of its assets, a
                  transaction with any person or group involving a merger,
                  consolidation, tender or exchange offer, recapitalization or
                  other business combination or similar transaction involving
                  the Company or its subsidiaries or that would result in any
                  person or group (other than the Company's Board of Directors)
                  having the right to elect or appoint a majority of the members
                  of the Company's Board of Directors, or any person or "group"
                  (as defined in the Exchange Act) has commenced or publicly
                  announced its intention to commence a tender or exchange offer
                  for more than 35% of the outstanding voting securities of the
                  Company.

         2. This Amendment to the Rights Agreement shall be effective as of
March 10, 2000.

         3. Except as expressly amended hereby, the Rights Agreement remains in
full force and effect in accordance with its terms.

         4. The Rights Agreement, as amended by this Agreement, and each Right
and each Rights Certificate exist under and pursuant to the Delaware General
Corporation Law.

         5. This Amendment to the Rights Agreement shall be governed by and
construed in accordance with the laws of the State of Delaware.


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

         7. Except as expressly set forth herein, this Amendment to the Rights
Agreement shall not by implication or otherwise alter, modify, amend or in any
way affect any of the terms, conditions, obligations, covenants or agreements
contained in the Rights Agreement, all of which are ratified and affirmed in all
respects and shall continue in full force and effect.

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




                                          MANOR CARE, INC.



                                          By:__________________________
                                             Name:
                                             Title:



                                          HARRIS TRUST AND SAVINGS BANK



                                          By:__________________________
                                             Name:
                                             Title:


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