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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G/A
Under the Securities Exchange Act of 1934
(Amendment No. 13)
VICOR CORPORATION
Common Stock, Par Value $.01 Per Share
925815 10 2
December 31, 2004
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
o Rule 13d-1 (b)
o Rule 13d-1 (c)
þ Rule 13d-1 (d)
| 13G/A | ||||||
| CUSIP No. 925815 10 2 | Page 2 of 6 Pages | |||||
| 1. | Name of Reporting Person: Patrizio Vinciarelli |
I.R.S. Identification Nos. of above persons (entities only): |
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| 2. | Check the Appropriate Box if a Member of a Group: | |||||
| (a) | o | |||||
| (b) | o | |||||
| 3. | SEC Use Only: | |||||
| 4. | Citizenship or Place of Organization: United States |
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| Number of Shares Beneficially Owned by Each Reporting Person With | ||||||
| 5. | Sole Voting Power: 20,986,203 | |||||
| 6. | Shared Voting Power: 0 | |||||
| 7. | Sole Dispositive Power: 20,986,203 | |||||
| 8. | Shared Dispositive Power: 0 | |||||
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person: 20,986,203 |
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| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares: o |
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| 11. | Percent of Class Represented by Amount in Row (9): 50.9% | |||||
| 12. | Type of Reporting Person: IN | |||||
| CUSIP No. 925815 10 2 | 13G/A | Page 3 of 6 Pages |
ITEM 1(A). NAME OF ISSUER:
Vicor Corporation
ITEM 1(B). ADDRESS OF ISSUER’S PRINCIPAL EXECUTIVE OFFICES:
25 Frontage Road, Andover, MA 01810
ITEM 2(A). NAME OF PERSON FILING:
Patrizio Vinciarelli
ITEM 2(B). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:
Vicor Corporation, 25 Frontage Road, Andover, MA 01810
ITEM 2(C). CITIZENSHIP:
United States
ITEM 2(D) TITLE OF CLASS OF SECURITIES:
Common Stock, par value $.01 per share
ITEM 2(E) CUSIP NUMBER:
925815 10 2
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULE 13D-1(B), OR 13D-2(B) OR (C), CHECK WHETHER THE PERSON FILING IS A:
Not applicable
| CUSIP No. 925815 10 2 | 13G/A | Page 4 of 6 Pages |
ITEM 4. OWNERSHIP.
Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.
(a) Amount beneficially owned: 20,986,203
As of December 31, 2004, Mr. Vinciarelli was the beneficial owner of 9,962,555 shares of Vicor Corporation Common Stock (which number includes 32,001 shares which Mr. Vinciarelli has the right to acquire upon the exercise of options to purchase Common Stock within 60 days of December 31, 2004). Additionally, he owned 11,023,648 shares of Vicor Corporation Class B Common Stock, which may be converted at any time into 11,023,648 shares of Common Stock.
(b) Percent of class:
50.9%
(c) Number of shares as to which such person has:
(i) Sole power to vote or to direct the vote: 20,986,203
(ii) Shared power to vote or to direct the vote: 0
(iii) Sole power to dispose or to direct the disposition of: 20,986,203
(iv) Shared power to dispose or to direct the disposition of: 0
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
Not applicable.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.
Not applicable.
| CUSIP No. 925815 10 2 | 13G/A | Page 5 of 6 Pages |
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.
Not applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
Not applicable.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP.
Not applicable.
ITEM 10. CERTIFICATION.
Not applicable.
| CUSIP No. 925815 10 2 | 13G/A | Page 6 of 6 Pages |
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
| Dated: January 31, 2005 | /s/ Patrizio Vinciarelli | |||
| Name: | Patrizio Vinciarelli | |||
| Title: | Chairman of the Board, President and Chief Executive Officer |
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