SC 13G 1 y30268sc13g.txt ORIGINAL FILING ON SCHEDULE 13G SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G (RULE 13d-102) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13d-1(b) (c), AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(b) Darwin Professional Underwriters, Inc. -------------------------------------------------------------------------------- (Name of Issuer) Common Stock -------------------------------------------------------------------------------- (Title of Class of Securities) 237502109 -------------------------------------------------------------------------------- (CUSIP Number) December 31, 2006 -------------------------------------------------------------------------------- (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: [ ] Rule 13d-1(b) [ ] Rule 13d-1(c) [X] Rule 13d-1(d) *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). ------------------- ----------------- CUSIP NO. 237502109 13G PAGE 2 OF 8 PAGES -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Alleghany Corporation -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)[ ] (b)[ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- NUMBER OF 5 SOLE VOTING POWER SHARES 0 BENEFICIALLY ---------------------------------------------------------------- OWNED BY 6 SHARED VOTING POWER EACH 9,371,096(1) REPORTING ---------------------------------------------------------------- PERSON 7 SOLE DISPOSITIVE POWER WITH 0 ---------------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 9,371,096(1) -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 9,371,096(1) -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 54.9% -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON CO -------------------------------------------------------------------------------- ---------- (1) The shares are beneficially owned directly by Alleghany Insurance Holdings LLC, a Delaware limited liability company. Alleghany Corporation, a Delaware corporation, owns 100% of the equity interest in Alleghany Insurance Holdings LLC. ------------------- ------------------ CUSIP NO. 237502109 13G PAGE 3 OF 8 PAGES -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Alleghany Insurance Holdings LLC -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)[ ] (b)[ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- NUMBER OF 5 SOLE VOTING POWER SHARES 0 BENEFICIALLY ---------------------------------------------------------------- OWNED BY 6 SHARED VOTING POWER EACH 9,371,096(2) REPORTING ---------------------------------------------------------------- PERSON 7 SOLE DISPOSITIVE POWER WITH 0 ---------------------------------------------------------------- 8 SHARED DISPOSITIVE POWER 9,371,096(2) -------------------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 9,371,096(2) -------------------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES -------------------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 54.9% -------------------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON OO -------------------------------------------------------------------------------- ---------- (2) The shares are beneficially owned directly by Alleghany Insurance Holdings LLC, a Delaware limited liability company. Alleghany Corporation, a Delaware corporation, owns 100% of the equity interest in Alleghany Insurance Holdings LLC. -------------------- ----------------- CUSIP NO. 237502109 13G PAGE 4 OF 8 PAGES -------------------- ----------------- INTRODUCTORY NOTE: This Statement is filed on behalf of Alleghany Corporation, a Delaware corporation, and by Alleghany Insurance Holdings LLC, a Delaware limited liability company and a wholly owned subsidiary of Alleghany Corporation. Each of Alleghany Corporation and Alleghany Insurance Holdings LLC expressly disclaims that it is a member of a "group". Item 1(a) Name of Issuer Darwin Professional Underwriters, Inc. Item 1(b) Address of Issuer's Principal Executive Offices 9 Farm Springs Road Farmington, CT 06032 Item 2(a) Name of Person Filing Alleghany Corporation ("Alleghany") Alleghany Insurance Holdings LLC ("AIHL") Item 2(b) Address of Principal Business Office or, if none, Residence The principal business address of each of Alleghany and AIHL is 7 Times Square Tower, 17th Floor, New York, NY 10036. Item 2(c) Citizenship Alleghany is a Delaware corporation. AIHL is a Delaware limited liability company. Item 2(d) Title of Class of Securities Common Stock Item 2(e) CUSIP Number 237502109 Item 3 If this statement is filed pursuant to Sections 240.13d-1(b) or 240.13-2(b) or (c), check whether the person filing is a: (a) [ ] Broker or Dealer registered under Section 15 of the Act (15 U.S.C. 78o); (b) [ ] Bank as defined in Section 3(a)(6) of the Act (15 U.S.C. 78c); (c) [ ] Insurance Company as defined in Section 3(a)(19) of the Act (15 U.S.C.78c); (d) [ ] Investment Company registered under Section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8); (e) [ ] An Investment Adviser in accordance with Section 240.13d-1(b)(1)(ii)(E); (f) [ ] An Employee Benefit Plan or Endowment Fund in accordance with Section 240.13d-1(b)(1)(ii)(F); (g) [ ] A Parent Holding Company or Control Person in accordance with Section 240.13d-1(b)(ii)(G); (h) [ ] A Savings Association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813); -------------------- ----------------- CUSIP NO. 237502109 13G PAGE 5 OF 8 PAGES -------------------- ----------------- (i) [ ] A Church Plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3); (j) [ ] Group, in accordance with Section 240.13d-1(b)(1)(ii)(J) Item 4 Ownership Alleghany AIHL --------- --------- (a) Amount beneficially owned 9,371,096 9,371,096 (b) Percent of class 54.9% 54.9% (c) Number of shares to which person has (i) sole power to vote or direct the vote None None (ii) shared power to vote or direct the vote 9,371,096 9,371,096 (iii) sole power to dispose or to direct disposition None None (iv) shared power to dispose or to direct disposition 9,371,096 9,371,096 Item 5 Ownership of Five Percent or Less of a Class If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following [ ]. Item 6 Ownership of More than Five Percent on Behalf of Another Person Not applicable. Item 7 Identification and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company. Not applicable. Item 8 Identification and Classification of Members of the Group Not applicable. Item 9 Notice of Dissolution of Group Not applicable. Item 10 Certification Not applicable. -------------------- ----------------- CUSIP NO. 237502109 13G PAGE 6 OF 8 PAGES -------------------- ----------------- SIGNATURE After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this Statement is true, complete and correct. February 12, 2007 ALLEGHANY CORPORATION By: /s/ Jerry G. Borrelli ----------------------------- Name: Jerry G. Borrelli Title: Vice President February 12, 2007 ALLEGHANY INSURANCE HOLDINGS LLC By: /s/ Roger B. Gorham ----------------------------- Name: Roger B. Gorham Title: Senior Vice President -------------------- ----------------- CUSIP NO. 237502109 13G PAGE 7 OF 8 PAGES -------------------- ----------------- EXHIBIT INDEX Exhibit No. ----------- 99.1 Joint Filing Agreement