Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Caggiano Michelle Marion
2. Date of Event Requiring Statement (Month/Day/Year)
04/29/2005
3. Issuer Name and Ticker or Trading Symbol
CENTRA SOFTWARE INC [CTRA]
(Last)
(First)
(Middle)
430 BEDFORD STREET
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
CHIEF FINANCIAL OFFICER
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

LEXINGTON, MA 02420
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (right to buy)   (1) 12/10/2009 Common Stock 19,000 $ 8 D  
Employee Stock Option (right to buy)   (2) 06/01/2010 Common Stock 4,000 $ 6.25 D  
Employee Stock Option (right to buy)   (3) 12/27/2010 Common Stock 10,000 $ 3.125 D  
Employee Stock Option (right to buy)   (4) 06/11/2012 Common Stock 15,000 $ 1.8 D  
Employee Stock Option (right to buy)   (5) 08/06/2013 Common Stock 20,000 $ 2.68 D  
Employee Stock Option (right to buy)   (6) 08/31/2014 Common Stock 25,000 $ 1.47 D  
Employee Stock Option (right to buy)   (7) 04/05/2015 Common Stock 100,000 $ 2.25 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Caggiano Michelle Marion
430 BEDFORD STREET
LEXINGTON, MA 02420
      CHIEF FINANCIAL OFFICER  

Signatures

Michelle M. Caggiano by Melinda J. Brown as atty in fact 05/04/2005
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) 4,750 of the Shares shall vest on November 1, 2000 and 6.25% of the Shares shall vest on each succeeding February 1, May 1, August 1, November 1 until (and including) on November 1, 2003.
(2) 1,000 of the Shares shall vest on June 1, 2001, and 6.25% of the Shares shall vest on each succeeding September 1, December 1, March 1, June 1 until (and including) on June 1, 2004.
(3) 625 of the Shares shall vest on March 27, 2001, and 625 of the Shares shall vest on each succeeding June 27, September 27, December 27 and March 27 until (and including) on December 27, 2004
(4) 937.50 of the Shares shall vest on August 06, 2002, and 937.50 of the Shares shall vest on each succeeding November 06, February 06, May 06 and August 06, until (and including) on May 06, 2006
(5) 1,250 of the Shares shall vest on November 01, 2003, and 1,250 of the Shares shall vest on each succeeding, February 01, May 01, August 01 and November 01 until (and including) on August 01, 2007.
(6) 12,500 of the Shares shall vest on August 01, 2005, and 12.50% of the Shares shall vest on November 01, 2005, February 01, 2006, May 01, 2006 and August 01, 2006.
(7) 6,250 of the Shares shall vest on July 01, 2005, and 6,250 of the Shares shall vest on each succeeding October 01, January 01, April 01, and July 01, until (and including) on April 01, 2009

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