Sec Form 4 Filing - IORDANOU CONSTANTINE @ ARCH CAPITAL GROUP LTD. - 2012-02-21

Insider filing report for Changes in Beneficial Ownership
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FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
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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1. Name and Address of Reporting Person
IORDANOU CONSTANTINE
2. Issuer Name and Ticker or Trading Symbol
ARCH CAPITAL GROUP LTD. [ ACGL]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
X __ Director _____ 10% Owner
X __ Officer (give title below) _____ Other (specify below)
Chairman, President & CEO
(Last) (First) (Middle)
WESSEX HOUSE, 5TH FLOOR, 45 REID STREET
3. Date of Earliest Transaction (MM/DD/YY)
02/21/2012
(Street)
HAMILTON, D0HM 12
4. If Amendment, Date Original Filed (MM/DD/YY)
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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Shares, $.0033 par value per share 02/21/2012 S( 3 ) 30,000 D $ 37.5588 ( 1 ) 904,213 D
Common Shares, $0033 par value per share 02/22/2012 S( 3 ) 13,854 D $ 37.6058 ( 2 ) 890,359 D
Common Shares, $.0033 par value per share 379,314 I By 2005 GRAT
Common Shares, $.0033 par value per share 116,613 I By Limited Liability Company
Series B Non-Cumulative Preferred Shares (non-convertible) 67,273.3862 I By 2010 GRAT
Series A Non-Cumulative Preferred Shares (non-convertible) 11,224.4855 I By 2010 GRAT
Series B Non-Cumulative Preferred Shares (non-convertible) 1,400 I By spouse
Common Shares, $.0033 par value per shar e 11,616 I By child
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(MM/DD/YY)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Reporting Owners
Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
IORDANOU CONSTANTINE
WESSEX HOUSE, 5TH FLOOR
45 REID STREET
HAMILTON, D0HM 12
X Chairman, President & CEO
Signatures
/s/ Constantine Iordanou 02/23/2012
Signature of Reporting Person Date
Explanation of Responses:
( 1 )Represents a weighted average sale price; the sales prices range from $37.5 to $37.665. Upon request, the full sale information regarding the number of shares sold at each price increment will be provided to the Commission or to a security holder of the issuer.
( 2 )Represents a weighted average sale price; the sales prices range from $37.55 to $37.66. Upon request, the full sale information regarding the number of shares sold at each price increment will be provided to the Commission or to a security holder of the issuer.
( 3 )A portion of the proceeds will be used to satisfy state and federal tax obligations.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4(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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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