SCHEDULE 13G
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. ____)*
ALTRA HOLDINGS, INC.
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
02208R106
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(CUSIP Number)
DECEMBER 31, 2007
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
[ X ] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities and Exchange Act
of 1934 ("Act") or otherwise subject to the liabilities of that section of the
Act but shall be subject to all other provisions of the Act (however, see the
Notes).
CUSIP No. 02208R106
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1. Names of Reporting Persons.
American Century Companies, Inc.
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2. Check the Appropriate Box if a Member of a Group. (See Instructions)
(a) [ ]
(b) [ ]
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3. SEC Use Only.
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4. Citizenship or Place of Organization.
Delaware
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Number of 5. Sole Voting Power. 1,294,141
Shares Bene- --------------------------------------------------------------
ficially Owned 6. Shared Voting Power. N/A
by Each --------------------------------------------------------------
Reporting 7. Sole Dispositive Power. 1,338,774
Person With: --------------------------------------------------------------
8. Shared Dispositive Power. N/A
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9. Aggregate Amount Beneficially Owned by Each Reporting Person. 1,338,774
10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares. (See
Instructions) [ ]
11. Percent of Class Represented by Amount in Row. (9) 5.1%
12. Type of Reporting Person. (See Instructions) HC
CUSIP No. 02208R106
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1. Names of Reporting Persons.
American Century Investment Management, Inc.
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2. Check the Appropriate Box if a Member of a Group. (See Instructions)
(a) [ ]
(b) [ ]
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3. SEC Use Only.
--------------------------------------------------------------------------------
4. Citizenship or Place of Organization.
Delaware
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Number of 5. Sole Voting Power. 1,294,141
Shares Bene- --------------------------------------------------------------
ficially Owned 6. Shared Voting Power. N/A
by Each --------------------------------------------------------------
Reporting 7. Sole Dispositive Power. 1,338,774
Person With: --------------------------------------------------------------
8. Shared Dispositive Power. N/A
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9. Aggregate Amount Beneficially Owned by Each Reporting Person. 1,338,774
10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares. (See
Instructions) [ ]
11. Percent of Class Represented by Amount in Row. (9) 5.1%
12. Type of Reporting Person. (See Instructions) IA
Item 1.
(a) Name of Issuer.
Altra Holdings, Inc.
(b) Address of Issuer's Principal Executive Offices.
14 Hayward Street
Quincy, Massachusetts 02171
Item 2.
(a) Name of Person Filing.
(1) American Century Companies, Inc.
(2) American Century Investment Management, Inc.
(b) Address of Principal Business Office or, if none, Residence.
4500 Main Street
9th Floor
Kansas City, MO 64111
(c) Citizenship.
(1) Delaware
(2) Delaware
(d) Title of Class of Securities.
Reference is made to the cover page of this filing.
(e) CUSIP Number.
Reference is made to the cover page of this filing.
Item 3. (1) American Century Companies, Inc. is a parent holding company or
control person in accordance with Section 240.13d-1(b)(1)(ii)(G).
(2) American Century Investment Management, Inc. is an investment
adviser in accordance with Section 240.13d-1(b)(1) (ii)(E).
Item 4. Ownership.
Reference is made to Items 5-9 and 11 on the cover pages of this
filing.
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 the following [ ].
Item 6. Ownership of More than Five Percent on Behalf of Another Person.
Various persons, including the investment companies and separate
institutional investor accounts that American Century Investment Management,
Inc. ("ACIM") serves as investment adviser, have the right to receive or the
power to direct the receipt of dividends from, or the proceeds from the sale of,
the securities that are the subject of this schedule. Except as may be otherwise
indicated if this is a joint filing, not more than 5% of the class of securities
that is the subject of this schedule is owned by any one client advised by ACIM.
Item 7. Identification and Classification of the Subsidiary Which Acquired the
Security Being Reported on By the Parent Holding Company.
See attached Exhibit A.
Item 8. Identification and Classification of Members of the Group.
Not applicable.
Item 9. Notice of Dissolution of Group.
Not applicable.
Item 10. Certification.
By signing below I certify that, to the best of my knowledge and belief,
the securities referred to above were acquired and are held in the ordinary
course of business and were not acquired and are not held for the purpose of or
with the effect of changing or influencing the control of the issuer of the
securities and were not acquired and are not held in connection with or as a
participant in any transaction having that purpose or effect.
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.
Date: February 12, 2008 AMERICAN CENTURY COMPANIES, INC. ("ACC")
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC. ("ACIM")
By: /s/ Jon W. Zindel
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Jon W. Zindel
Senior Vice President, ACIM
Vice President, ACC
SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(b) or
13d-2(b).
EXHIBIT A
This Exhibit has been prepared to identify each subsidiary of American
Century Companies, Inc. ("ACC") that is a beneficial owner of securities that
are the subject of this schedule (the "Subject Securities"). American Century
Investment Management, Inc. ("ACIM") is a wholly-owned subsidiary of ACC and an
investment adviser registered under Section 203 of the Investment Advisers Act
of 1940.
SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(b) or
13d-2(b) and Rule 13d-1(f)(1) Agreement.
EXHIBIT B
Rule 13d-1(f)(1)(iii) Agreement
Each of the undersigned hereby agrees and consents to the execution and joint
filing on its behalf by American Century Investment Management, Inc. of this
Schedule 13G respecting the beneficial ownership of the securities which are the
subject of this schedule.
Dated this 12th day of February, 2008.
AMERICAN CENTURY COMPANIES, INC. ("ACC")
AMERICAN CENTURY INVESTMENT MANAGEMENT, INC. ("ACIM")
By: /s/ Jon W. Zindel
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Jon W. Zindel
Senior Vice President, ACIM
Vice President, ACC