Exhibit 5.2

13 December 2013

Matter No.:319142

Doc Ref: Legal - 4433792

(441) 299-4993

jason.piney@conyersdill.com

Arch Capital Group Ltd.

Wessex House, 5th Floor

45 Reid Street

Hamilton HM12

Bermuda

Dear Sirs,

Re: Arch Capital Group Ltd. (the “Company”)

We have acted as special Bermuda legal counsel to the Company in connection with the proposed issuance and sale by Arch Capital Group (U.S.) Inc. (the “Issuer”) of US$500,000,000 aggregate principal amount of the Issuer’s 5.144% Notes due 2043 (the “Notes”), pursuant to the Purchase Agreement, dated 10 December 2013, among the Issuer, the Company and J.P. Morgan Securities LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC, as representatives of the several underwriters named therein (the “Purchase Agreement”).  The obligations of the Issuer under the Notes will be fully and unconditionally guaranteed by the Company (the “Guarantee,” and together with the Notes, the “Securities”).  The Securities will be issued and sold pursuant the prospectus supplement dated 10 December 2013 (the “Prospectus Supplement”), supplementing the prospectus dated 23 March 2012 (the “Base Prospectus”) that forms part of the Registration Statement (File No. 333-180329) of the Company.  As used in this letter, the term “Prospectus” means the Prospectus Supplement and the Base Prospectus, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act of 1933, as amended (the “Securities Act”).  The Securities will be issued pursuant to an Indenture, dated as of 13 December 2013 (the “Original Indenture”), by and among the Issuer, the Company and The Bank of New York Mellon, as trustee (the “Trustee”), as supplemented by the First Supplemental Indenture, dated as of 13 December 2013 (the “First Supplemental Indenture,” and together with the Original Indenture, the “Indenture”), by and among the Issuer, the Company and the Trustee.

For the purposes of giving this opinion, we have examined copies of the Prospectus, the Registration Statement, the Purchase Agreement, the Indenture and resolutions of the Board of Directors of the Company adopted on 8 November 2013 and resolutions of the Special Committee of the Board of Directors of the Company adopted on 9 December 2013 (together, the “Resolutions”).  We have also reviewed the memorandum of association and the bye-laws of the Company (together, the “Constitutional Documents”), each certified by the Assistant Secretary of the Company on 11 December 2013, and such other documents and made such enquiries as to questions of law as we have deemed necessary in order to render the opinion set forth below.

We have assumed (a) the genuineness and authenticity of all signatures and the conformity to the originals of all copies (whether or not certified) examined by us and the authenticity and completeness of the originals from which such copies were taken, (b) that where a document has been examined by us in draft form, it will be or has been executed and/or filed in the form of that draft, and where a number of drafts of a document have been examined by us all changes thereto have been marked or otherwise drawn to our attention, (c) the accuracy and completeness of all factual representations made in the Indenture, the Guarantee thereunder and other documents reviewed by us, (d) that the Company will enter into the Guarantee in furtherance of its objects as set out in its memorandum of association, (e) that the Constitutional Documents will not be amended in any manner that would affect the opinions expressed herein, (f) that the Resolutions were passed at one or more duly convened, constituted and quorate meetings, or by unanimous written resolutions, remain in full force and effect and have not been rescinded or amended, (g) that there is no provision of the law of any jurisdiction, other than Bermuda, which would have any implication in relation to the opinions expressed herein, (h) that the Indenture and the Guarantee thereunder, is valid and binding in accordance with its terms pursuant to its governing law, (i) the capacity, power and authority of all parties other than the Company to enter into and perform their obligations under any and all documents entered into by such parties in connection with the Indenture and the Guarantee thereunder, and the due execution and delivery thereof by each party thereto, (j) that none of the parties to the Indenture and the Guarantee thereunder (other than the Company) carries on business from premises in Bermuda, at which it employs staff and pays salaries and other expenses, and (k) at the time of issue of the Guarantee, the Company will be able to pay its liabilities as they become due.

The obligations of the Company in connection with the Indenture and the Guarantee thereunder (a) will be subject to the laws from time to time in effect relating to bankruptcy, insolvency, liquidation, possessory liens, rights of set off, reorganisation, amalgamation, merger, moratorium or any other laws or legal procedures, whether of a similar nature or otherwise, generally affecting the rights of creditors as well as applicable international sanctions, (b) will be subject to statutory limitation of the time within which proceedings may be brought, (c) will be subject to general principles of equity and, as such, specific performance and injunctive relief, being equitable remedies, may not be available, (d) may

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not be given effect to by a Bermuda court if and to the extent they constitute the payment of an amount which is in the nature of a penalty and not in the nature of liquidated damages, and (e)  may not be given effect by a Bermuda court to the extent that they are to be performed in a jurisdiction outside Bermuda and such performance would be illegal under the laws of that jurisdiction. Notwithstanding any contractual submission to the jurisdiction of specific courts, a Bermuda court has inherent discretion to stay or allow proceedings in the Bermuda courts.

We have made no investigation of and express no opinion in relation to the laws of any jurisdiction other than Bermuda.  This opinion is to be governed by and construed in accordance with the laws of Bermuda and is limited to and is given on the basis of the current law and practice in Bermuda. This opinion is issued solely for the purposes of the issuance by the Company of the Guarantee and is not to be relied upon in respect of any other matter.

On the basis of and subject to the foregoing we are of the opinion that:

1.              The Company is duly incorporated and existing under the laws of Bermuda and is in good standing (meaning solely that it has not failed to make any filing with any Bermuda governmental authority or to pay any Bermuda government fee or tax which would make it liable to be struck off the Register of Companies and thereby cease to exist under the laws of Bermuda).

2.              When the Notes shall have been duly executed by the Issuer and authenticated by the Trustee as provided in the Indenture and shall have been duly delivered to the purchasers thereof against payment of the agreed consideration therefor as provided in the Purchase Agreement, the Guarantee will be validly issued and will constitute a valid and legally binding obligation of the Company in accordance with the terms thereof.

We hereby consent to the filing of this opinion as an exhibit to the filing by the Company of a Current Report on Form 8-K on the date hereof, which Form 8-K will be incorporated by reference into the Registration Statement, and to all references to our firm included in or made a part of the Prospectus.  In giving such consent, we do not hereby admit that we are experts within the meaning of Section 11 of the Securities Act or that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations of the Securities and Exchange Commission promulgated thereunder.

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