SEC FORM 4

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

IORDANOU CONSTANTINE

(Last)

(First)

(Middle)

WESSEX HOUSE, 5TH FLOOR

45 REID STREET

(Street)

HAMILTON

HM 12

(City)

(State)

(Zip)

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

3. Date of Earliest Transaction (Month/Day/Year)
01/01/2012

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Shares, $.0033 par value per share	01/01/2012		M		719,615	A	$7.8333	1,091,660	D
Common Shares, $.0033 par value per share	01/01/2012		F		151,403⁽³⁾	D	$37.23	940,257	D
Common Shares, $.0033 par value per share	01/01/2012		M		480,385	A	$7.8333	480,385	I	By 2005 GRAT
Common Shares, $.0033 par value per share	01/01/2012		F		101,071⁽⁴⁾	D	$37.23	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 share								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 (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	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 (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (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: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Stock Option (right to buy)	$7.8333							⁽¹⁾	01/01/2012	Common Shares, $.0033 par value per share	719,615⁽²⁾		719,615	D
Stock Option (right to buy)	$7.8333							⁽¹⁾	01/01/2012	Common Shares, $.0033 par value per share	480,385		480,385	I	By 2005 GRAT
Stock Option (right to buy)	$7.8333	01/01/2012		M			719,615	⁽¹⁾	01/01/2012	Common Shares, $.0033 par value per share	719,615	$0	0	D
Stock Option (right to buy)	$7.8333	01/01/2012		M			480,385	⁽¹⁾	01/01/2012	Common Shares, $.0033 par value per share	480,385	$0	0	I	By 2005 GRAT

Explanation of Responses:

1. The stock option became exercisable in three equal annual installments with the first installment being exercisable on January 1, 2002 and the second and third installments being exercisable on Jaunuary 1, 2003 and January 1, 2004.

2. 167,258 of the 719,615 stock options were previously reported as indirectly owned by the 2005 GRAT; on December 21, 2011, the 2005 GRAT distributed 167,258 of such stock options to the reporting person and as a result, the reporting person directly owns 719,615 stock options.

3. On January 1, 2012, the reporting person exercised 719,615 stock options and, under the net settlement provisions of the applicale stock option agreement, 151,403 common shares were withheld in payment of the exercise price.

4. On January 1, 2012, the reporting person's 2005 GRAT exercised 480,385 stock options and, under the net settlement provisions of the applicale stock option agreement, 101,071 common shares were withheld in payment of the exercise price.

	/s/ Louis T. Petrillo, Attorney in fact	01/03/2012
	** Signature of Reporting Person	Date
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).
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