UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 8-K

Current Report Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934

March 26, 2012

Date of Report (Date of earliest event reported)

Arch Capital Group Ltd.

(Exact name of registrant as specified in its charter)

Wessex House, 45 Reid Street, Hamilton HM 12, Bermuda

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code:
(441) 278-9250

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

ITEM 7.01             Regulation FD Disclosure.

On March 26, 2012, Arch Capital Group Ltd. (the “Company”) announced that it has launched a public offering to sell its Series C Non-Cumulative Preferred Shares.  The Company intends to use the net proceeds of this offering to redeem all of its outstanding Series A Non-Cumulative Preferred Shares.  Any net proceeds in excess of the amount required to redeem the Series A Non-Cumulative Preferred Shares will be used to redeem the Series B Non-Cumulative Preferred Shares and/or for general corporate purposes.  The Company intends to apply to have the Series C Non-Cumulative Preferred Shares listed on the NYSE.

This Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state in which the offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such state.  The offering is being made pursuant to the Company’s effective registration statement previously filed with the Securities and Exchange Commission.  Any offer will be made only by means of a prospectus, including a prospectus supplement, forming a part of the effective registration statement.

The information in this Current Report on Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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