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As filed with the Securities and Exchange Commission on March 25, 2004
Registration No. 333-            

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549


FORM S-8
REGISTRATION STATEMENT
Under
The Securities Act of 1933

CIPHERGEN BIOSYSTEMS, INC.
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of
incorporation or organization)		   33-059-5156
(I.R.S. Employer
Identification No.)

6611 Dumbarton Circle
Fremont, CA 94555
(510) 505-2100
(Address, including zip code, of registrant's Principal Executive Offices)

2000 STOCK PLAN
2000 EMPLOYEE STOCK PURCHASE PLAN
(Full titles of the Plans)

William E. Rich
President and Chief Executive Officer
Ciphergen Biosystems, Inc.
6611 Dumbarton Circle
Fremont, CA 94555
(510) 505-2100
(Name, address and telephone number, including area code, of agent for service)

Copies to:
Michael J. O'Donnell
Wilson Sonsini Goodrich & Rosati
Professional Corporation
650 Page Mill Road
Palo Alto, CA 94304
(650) 493-9300

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities
to be Registered
   Amount
to be
Registered
   Proposed
Maximum
Offering Price
Per Share
   Proposed
Maximum
Aggregate
Offering Price
   Amount of
Registration Fee
2000 Stock Plan
Common Stock, $0.001 par value		   1,400,000 shares   $7.96 (1) $11,144,000.00 (1) $1,411.95
2000 Employee Stock Purchase Plan
Common Stock, $0.001 par value		   290,795 shares   $6.77 (2) $1,967,518.97 (2) $249.28
Total   1,690,795 shares       $13,111,518.97   $1,661.23
(1)
Calculated in accordance with Rule 457(h) and (c) under the Securities Act of 1933, as amended, solely for the purpose of calculating the registration fee. The computation is based upon the average of the high and low price of the Common Stock as reported on the Nasdaq National Market on March 23, 2004, equal to $7.96 per share.

(2)
Calculated in accordance with Rule 457(h) and (c) under the Securities Act of 1933, as amended, solely for the purpose of calculating the registration fee. The computation is based upon 85% of the average of the high and low price of the Common Stock as reported on the Nasdaq National Market on March 23, 2004, equal to $6.77 per share. Pursuant to the 2000 Employee Stock Purchase Plan, which Plan is incorporated by reference herein, the Purchase Price of a share of Common Stock shall mean an amount equal to 85% of the Fair Market Value of a share of Common Stock on the Enrollment Date or the Exercise Date, whichever is lower.


CIPHERGEN BIOSYSTEMS, INC.
REGISTRATION STATEMENT ON FORM S-8

EXPLANATORY NOTE

        The contents of the Registration Statement No. 333-53530 on Form S-8 as filed with the Securities and Exchange Commission (the "Commission") on May 23, 2003 are hereby incorporated herein by reference to the extent not replaced hereby.

        The purpose of this Form S-8 is to register the following:


PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Information Incorporated by Reference.

        The following documents and information previously filed with the Securities and Exchange Commission are incorporated herein by reference:

        All documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act subsequent to the filing of this Registration Statement and prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be part hereof from the date of filing of such documents.


Item 8. Exhibits.

Exhibit Number
   Exhibit Document
4.1   2000 Stock Plan (incorporated by reference to Exhibit 10.5 of the Registrant's Form S-1, File No. 333-32812)
4.2   2000 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.6 of the Registrant's Form S-1, File No. 333-32812)
5.1   Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation, as to the legality of securities being registered
23.1   Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation (contained in Exhibit 5.1 hereto)
23.2   Consent of PricewaterhouseCoopers LLP, Independent Accountants
24.1   Power of Attorney (see page II-3)

II-1


SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Fremont, State of California on March 24, 2004.

    CIPHERGEN BIOSYSTEMS, INC.

 
 
By:
/s/  WILLIAM E. RICH      
William E. Rich, Ph.D.
 President and Chief Executive Officer

II-2


POWER OF ATTORNEY

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints William E. Rich and Matthew J. Hogan, jointly and severally, his attorney-in-fact, each with the power of substitution, for him in any and all capacities, to sign any amendments to this Registration Statement on Form S-8, and to file the same, with exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, hereby ratifying and confirming all that each of said attorney-in-fact, or his substitute or substitutes, may do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the date indicated.

SIGNATURE
   TITLE
   DATE
/s/  WILLIAM E. RICH      
William E. Rich		   Director, President and Chief Executive Officer (Principal Executive Officer)   March 24, 2004

/s/  MATTHEW J. HOGAN      
Matthew J. Hogan
 
Senior Vice President and Chief Financial Officer (Principal Financial Officer)
 
March 24, 2004

/s/  DANIEL M. CASERZA      
Daniel M. Caserza
 
Corporate Controller (Principal Accounting Officer)
 
March 24, 2004

/s/  JOHN A. YOUNG      
John A. Young
 
Chairman of Board
 
March 24, 2004

/s/  MICHAEL J. CALLAGHAN      
Michael J. Callaghan
 
Director
 
March 24, 2004

/s/  RAJEN DALAL      
Rajen Dalal
 
Director
 
March 24, 2004

/s/  JAMES L. RATHMANN      
James L. Rathmann
 
Director
 
March 24, 2004

/s/  WENDELL WIERENGA      
Wendell Wierenga
 
Director
 
March 24, 2004

/s/  JUDY BRUNER      
Judy Bruner
 
Director
 
March 24, 2004

II-3


INDEX TO EXHIBITS

Exhibit Number
   Exhibit Document

4.1
 
2000 Stock Plan (incorporated by reference to Exhibit 10.5 of the Registrant's Form S-1, File No. 333-32812)

4.2
 
2000 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.6 of the Registrant's Form S-1, File No. 333-32812)

5.1
 
Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation, as to the legality of securities being registered

23.1
 
Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation (contained in Exhibit 5.1 hereto)

23.2
 
Consent of PricewaterhouseCoopers LLP, Independent Accountants

24.1
 
Power of Attorney (see page II-3)


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CIPHERGEN BIOSYSTEMS, INC. REGISTRATION STATEMENT ON FORM S-8 EXPLANATORY NOTE
PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
SIGNATURES
POWER OF ATTORNEY
INDEX TO EXHIBITS