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SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549


FORM 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16
of the Securities Exchange Act of 1934

For the month of April 2005

Commission File Number 000-31815

Hydrogenics Corporation

5985 McLaughlin Road
Mississauga, Ontario
Canada, L5R 1B8

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F   o   Form 40-F   ý

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by
Regulation S-T Rule 101(b)(1):                              

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by
Regulation S-T Rule 101(b)(7):                              

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes   o   No   ý

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with
Rule 12g3-2(b): 82-                             





EXHIBIT LIST

Exhibit
  Description
99.1   Hydrogenics Corporation 2004 Annual Report
99.2   Hydrogenics Corporation Proxy Circular
99.3   Hydrogenics Corporation Form of Proxy
99.4   Hydrogenics Corporation Notice of Annual and Special Meeting of Shareholders
99.5   Invitation to Shareholders


SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: April 22, 2005

    HYDROGENICS CORPORATION

 

 

By:

/s/  
PIERRE RIVARD      
Name: Pierre Rivard
Title: President, Chief Executive Officer and Director



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EXHIBIT LIST
SIGNATURES