UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No.__)*
Platinum Underwriters Holdings, Ltd.
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(Name of Issuer)
Common Stock, Par Value $.001 Per Share
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(Title of Class of Securities)
G7127P100
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(CUSIP Number)
December 31, 2009
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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 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. G7127P100
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1 NAME OF REPORTING PERSON
SS OR IRS IDENTIFICATION NO. OF ABOVE PERSON
Aronson+Johnson+Ortiz, LP
23-2312104
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2 CHECK APPROPRIATE BOX IF A MEMBER OF A GROUP (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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5 SOLE VOTING POWER
1,742,700
NUMBER OF --------------------------------------------------------------
SHARES 6 SHARED VOTING POWER
BENFICIALLY
OWNED BY 0
EACH --------------------------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON
WITH 2,559,200
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8 SHARED DISPOSITIVE POWER
0
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9 AGGREGATE AMOUNT BENFICIALLY OWNED BY EACH REPORTING PERSON
2,559,200
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 9 EXCLUDES CERTAIN SHARES |_|
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.1%
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12 TYPE OF REPORTING PERSON
IA
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Item 1.
a) Name of Issuer: Platinum Underwritings Holdings, Ltd.
b) Address: The Belvedere Building, 69 Pitts Bay Road
Pembroke, HM 08 Bermuda
Item 2.
a) Name of Filer: Aronson+Johnson+Ortiz, LP
b) Address of Filer: 230 S. Broad Street, 20th Floor
Philadelphia, PA 19102
c) Citizenship: Delaware
d) Title of Class of Securities: Common Stock, Par Value $.001
e) CUSIP Number: G7127P100
Item 3. Item 3. If this statement is filed pursuant to Rule 13d-1(b), or
13d-2(b), check whether the person filing is a:
(a) |_| Broker or Dealer registered under Section 15 of the Act
(b) |_| Bank as defined in section 3 (a) (6) of the Act
(c) |_| Insurance Company as defined in section 3 (a) (6) of the Act
(d) |_| Investment Company registered under section 8 of the
Investment Company Act
(e) |X| Investment Adviser registered under section 203 of the
Investment Advisers act of 1940
(f) |_| Employee Benefit Plan, Pension Fund which is subject to the
provisions of the Employee Retirement Income Security Act of
1974 or Endowment Fund; see 240.13d-1 (b) (1) (ii) (F)
(g) |_| Parent Holding Company, in accordance with 240.13d-1 (b) (ii)
(G) (Note: See Item 7)
(h) |_| Group, in accordance with 240.13d-1(b) (1) (ii) (H)
Item 4. Ownership
a) Amount beneficially owned: 2,559,200
b) Percent of Class: 5.1%
c) Number of shares:
(i) Sole voting power -- 1,742,700
(ii) Shared voting power -- 0
(iii) Sole disposal power -- 2,559,200
(iv) Shared disposal power - 0
Item 5. Less than 5% beneficial ownership
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. More than 5% on behalf of another person
The securities as to which this schedule is filed by
Aronson+Johnson+Ortiz, LP, in its capacity as investment
adviser, are owned of record by clients of Aronson+Johnson+Ortiz,LP.
No such client is known to own more than five percent of this
class of securities.
Item 7. Subsidiary na
Item 8. If group na
Item 9. Notice of Dissolution na
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 transaction having
such purposes 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.
February 12, 2010
Date
Aronson+Johnson+Ortiz, LP
By: /s/ Joseph F. Dietrick, Chief Compliance Officer
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Name, Title