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 OF SECURITIES 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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(Print or Type Responses)

1. Name and Address of Reporting Person * GRANDISSON MARC   2. Issuer Name and Ticker or Trading Symbol ARCH CAPITAL GROUP LTD. [ACGL] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) President & CEO (Last) (First) (Middle) C/O ARCH CAPITAL GROUP LTD., WATERLOO HOUSE, 100 PITTS BAY ROAD 3. Date of Earliest Transaction (Month/Day/Year) 05/09/2018 (Street) PEMBROKE, D0 HM 08 4. If Amendment, Date 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 (City) (State) (Zip) 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) Code V Amount (A) or (D) Price Common Shares, $.0033 par value per share 05/09/2018   M   30,000 A $ 23.1 638,762 I See Footnote (2) Common Shares, $.0033 par value per share 05/09/2018   F(3)   8,731 D $ 79.38 630,031 I See Footnote (2) Common Shares, $.0033 par value per share               660 I By spouse

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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 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

Share Appreciation Right

$ 23.1

05/09/2018

M

30,000

(1)

05/09/2018

Common Shares, $.0033 par value per share

30,000

$ 0

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
GRANDISSON MARC C/O ARCH CAPITAL GROUP LTD. WATERLOO HOUSE, 100 PITTS BAY ROAD PEMBROKE, D0 HM 08			President & CEO

Signatures

/s/ Marc Grandisson		05/11/2018
**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	The share appreciation right became exercisable in three equal annual installments, with the first installment becoming exercisable on May 9, 2009 and the next two installments on May 9, 2010 and May 9, 2011, subject to the applicable award agreement.
(2)	The reporting person holds such common shares indirectly with his spouse.
(3)	In connection with the exercise of the share appreciation rights award described in Table II, 8,731 common shares were disposed of in satisfaction of the exercise price. The reporting person received a net issuance of 21,269 common shares.

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