SECURITIES EXCHANGE COMMISSION
Washington, DC 20549
Under the Securities Exchange Act of 1934
(Amendment No. 4)
ADAPTEC, INC
(Name of Issuer)
Common
(Title of Class of Securities)
Date of Event Which Requires Filing of this Statement
December 31, 2004
Check the appropriate box to designate the rule
pursuant to which this Schedule is filed
[ ] Rule 13d-1(b)
[X] Rule 13d-1(c)
[ ] Rule 13d-1(d)
00651F108
(CUSIP NUMBER)
1) Name of Reporting Pioneer Global Asset Person Management S.p.A.
IRS Identification 98-0362802
No. of Above
2) Check the Appropriate Box (a)
of A Member of Group
(See Instructions) (b)
3) SEC Use Only
4) Citizenship of Place of
Organization Italy
Number of (5)Sole Voting
Shares Power 6,245,730
Beneficially Owned (6)Shared Voting
by Each Reporting Power 0
Person With (7)Sole Disposi-
tive Power 6,245,730
(8)Shared Disposi-
tive Power 0
9) Aggregate Amount Beneficially 6,245,730
Owned by Each
Reporting Person
10) Check if the aggregate Amount in Row (9) Exclude Certain Shares (See
Instructions)
11) Percent of Class Represented
By Amount in Row 9. 5.43%
12) Type of Reporting
Person (See Instructions) HC
Item 1(a) Name of Issuer.
ADAPTEC, INC.
Item 1(b) Address of Issuer's Principal Executive Offices:
Mr. Marshall L. Mohr
Vice President and CFO
691 South Milpitas Blvd
Milpitas, CA 95035
Item 2(a) Name of Person Filing:
Pioneer Global Asset Management S.p.A.
Item 2(b) Address of Principal Business Office:
Galleria San Carlo 6,
20122 Milan, Italy
Item 2(c) Citizenship:
Italy
Item 2(d) Title of Class of Securities:
Common Stock
Item 2(e) CUSIP Number:
00651F108
Item 3 The person filing this statement pursuant to Rule 13d-1(b)
or 13d-2(b) is:
(Inapplicable)
Item 4. Ownership.
(a) Amount Beneficially Owned: 6,245,730
(b) Percent of Class: 5.43%
(c) Number of shares as to which such person has
(i) sole power to vote or to direct the vote 6,245,730
(ii) shared power to vote or to direct vote 0
(iii) sole power to dispose or to direct disposition of 6,245,730
(iv) shared power to dispose or to direct disposition 0
Item 5. Ownership of Five Percent or Less of a Class.
If this statement is being filed to report the fact that as of the date Hereof
the reporting person has ceased to be the beneficial owner of more than five
percent of the class of securities, check here:
Item 6. Ownership of More than Five Percent on Behalf of Another Person.
Inapplicable.
Item 7. Identification and Classification of the Subsidiary Which Acquired
the Security Being Reported On By the Parent Holding Company.
Inapplicable.
Item 8. Identification and Classification of Members of the Group.
Inapplicable.
Item 9. Notice of Dissolution of the Group.
Inapplicable.
Item 10. Certification.
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired in the ordinary course of
business and were not acquired for the purpose of and do not have the effect of
changing or influencing the control of the issuer of such securities and were
not acquired in connection with or as a participant in any transactions having
such purposes or effect.
After reasonable inquiry and to the best of my knowledge and believe, I
certify that the information set forth in this statement is true, complete and
correct.
February 10, 2005
Date
/s/Dario Frigerio
Name: Dario Frigerio
Title: Chief Executive Officer