Exhibit 4.20

6 July 2001

|Separation Agreement                               
|---------------------------------------------------
|                                                   
|                                                   
|between                                            
|                                                   
|                                                   
|Sulzer AG,Zürcherstrasse 12, 8400 Winterthur       
|                                                   
|hereinafter "SUAG"                                 
|                                                   
|and                                                
|                                                   
|Sulzer Medica AG,Zürcherstrasse 12, 8400 Winterthur
|                                                   
|hereinafter "MEAG"                                 
|                                                   

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TABLE OF CONTENTS

|   |                       |                                                          |   | Page
|-- | --------------------- | -------------------------------------------------------- | - | ----
|A. | SEPARATION            |                                                          | 2
|   | 1                     | General Principles                                       |   | 2   
|   | 2                     | General Shareholders' Meeting of MEAG                    |   | 2   
|   | 3                     | Intellectual Property Rights and Use of the Name of SUAG |   | 2   
|   | 4                     | Services and Cooperation Agreements                      |   | 3   
|   | 5                     | Fiduciary Holdings                                       |   | 4   
|B. | INDEMNITY ARRANGEMENT |                                                          | 5
|   | 6                     | Rightful Claimants                                       |   | 5   
|   | 7                     | Mutual Compensation for Business Liabilities             |   | 5   
|   | 8                     | Mutual Compensation for Tax Liabilities                  |   | 5   
|   | 9                     | Mutual Compensation for Prospectus Liabilities           |   | 6   
|   | 10                    | Procedure Related to Third Party Claims                  |   | 6   
|C. | MISCELLANEOUS         |                                                          | 7
|   | 11                    | Costs                                                    |   | 7   
|   | 12                    | Conditions                                               |   | 7   
|   | 13                    | Access to Books and Records                              |   | 7   
|   | 14                    | Announcements                                            |   | 7   
|   | 15                    | Non-Assignment                                           |   | 7   
|   | 16                    | Changes and Modifications of the Agreement               |   | 7   
|   | 17                    | Notices                                                  |   | 8   
|   | 18                    | Obligations of SUAG and MEAG                             |   | 8   
|   | 19                    | Applicable Law and Arbitration Clause                    |   | 8   

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PREAMBLE



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4

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6

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|Winterthur, 6 July 2001 |  |                       
|----------------------- |  | ----------------------
|                        |  |                       
|Sulzer AG               |  | Sulzer Medica AG      
|                        |  |                       
|                        |  |                       
|/s/ Roman Beran         |  | /s/ H. Georg Hahnloser
|                        |  |                       
|/s/ Kurt Hägi           |  | /s/ Vanessa Oelz      

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Index of Annexes

|Annex A      | Master Agreement as of 4 July 1997                                      
|------------ | ------------------------------------------------------------------------
|Annex 4.2 a) | Administration and Service Agreement (Verwaltungsdienstleistungsvertrag)
|Annex 4.2 b) | R&D Cost-Sharing Agreement                                              
|Annex 4.2 c) | Dissolution Agreement / Assignment Agreement                            
|Annex 4.4    | Leased space SOAG Winterthur                                            
|Annex 4.6    | Memo as of 27 June 2001 regarding personal and property insurances      
|Annex 4.9    | Agreement on pension funds (Pensionskassen-Anschlussvertrag)            

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Annex 4.4 to the Separation Agreement

between
Sulzer AG, Zürcherstrasse 12, 8400 Winterthur ("SUAG") and Sulzer Medica AG, Zürcherstrasse 12, 8400 Winterthur
("MEAG")

With
reference to section 4.4 of the Separation Agreement SUAG and MEAG have agreed on the following with regard to the additional needs of Sulzer Orthopädie AG
("SOAG") for office and production space at the location of SOAG on the industry area in Oberwinterthur:

In
order to ensure the current location of SOAG in Oberwinterthur for a medium- up to long-term, SOAG presumably requires approx. 2,000 square meter additional office space and approx.
3,000 square meter additional production space within the next 1 to 5 years.

Currently
unrented office and production space is available in the existing buildings nos. 579, 615 (production), 530, 622, 731 (office) on the industry area in Oberwinterthur. SUAG acknowledges that
MEAG herewith declares its interest in such space for the benefit of SOAG. Additionally, or as
alternative during the transition period to the occupancy described above, SOAG intendswhereby the necessary parking space must be ensuredto expand the office building 540
and the production building 541 as well as the office pavilion 577 (addition of storey).

SUAG
shall primarily consider MEAG in case all or part of such space is intended to be rented or sold to a third party and shall at the same time give MEAG or SOAG respectively the opportunity to
submit an offer to rent or purchase.

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