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	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	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* Sills Stephen Jay (Last) (First) (Middle) 9 FARM SPRINGS ROAD (Street) FARMINGTON CT 06032 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Darwin Professional Underwriters Inc [ DR ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner X Officer (give title below) Other (specify below) President and CEO
	3. Date of Earliest Transaction (Month/Day/Year) 02/23/2007
	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)
			Code	V	Amount	(A) or (D)	Price
Common Stock	02/23/2007		A		5,803(1)	A	$25.3(1)	665,903(2)	D
Common Stock								65,200(3)	I	By Trust(4)
Common Stock								1,000(5)	I	By Child(6)
Common Stock								900(7)	I	By Child(6)
Common Stock								900(7)	I	By reporting person as UTMA custodian(6)
Common Stock								1,050(8)	I	By child(6)

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option (right to buy)	$25.3	02/23/2007		A		14,365		(9)	02/23/2017	common stock	14,365	(9)	72,152(10)	D
Employee Stock Option (right to buy)	$16							(11)	05/19/2016	common stock	57,787		57,787(10)	D

Explanation of Responses:

1. Restricted stock award granted under Issuer's 2006 Stock Incentive Plan; price represents mean value of the high and low trades on the NYSE Arca exchange on February 23, 2007, the grant date, as per Plan spefication.

2. Amount reflects the effect of a 33-for-2 stock split that became effective on May 19, 2006, the initial public offering date of the issuer's common stock (the "stock split"). Pre-split amount shown as 40,006.06 shares in prior filing, now represents 660,100 post-split shares.

3. Amount reflects the effect of a 33-for-2 stock split that became effective on May 19, 2006, the initial public offering date of the issuer's common stock (the "stock split"). Pre-split amount shown as 3787.88 shares in prior filing, now represents 62,500 post-split shares.

4. Held by grantor annuity trust of which the reporting person is sole trustee and beneficiary.

5. Amount reflects the effect of a 33-for-2 stock split that became effective on May 19, 2006, the initial public offering date of the issuer's common stock (the "stock split"). Pre-split amount shown as 60.61 shares in prior filing, now represents 1,000 post-split shares.

6. Reporting person disclaims beneficial ownership of these shares.

7. Amount reflects the effect of a 33-for-2 stock split that became effective on May 19, 2006, the initial public offering date of the issuer's common stock (the "stock split"). Pre-split amount shown as 54.55 shares in prior filing, now represents 900 post-split shares.

8. Amount reflects the effect of a 33-for-2 stock split that became effective on May 19, 2006, the initial public offering date of the issuer's common stock (the "stock split"). Pre-split amount shown as 63.64 shares in prior filing, now represents 1050 post-split shares.

9. Employee stock option, granted 02/23/2007, under the issuer's 2006 Stock Incentive Plan (the "Plan") at a fair market value determined in accordance with the Plan of $25.30 per share. Exercisable up to an aggregate of 25% on or after 02/23/2008, up to an aggregate 50% on or after 02/23/2009, up to an aggregate 75% on or after 02/23/2010 and in its entirety on or after 02/23/2011, subject to expiration or forfeiture in accordance with the Plan.

10. Amount reflects the effect of a 33-for-2 stock split that became effective on May 19, 2006, the initial public offering date of the issuer's common stock (the "stock split"). Pre-split amount shown as 3502.24 shares in prior filing, now represents 57,787 post-split shares.

11. The option vests in four equal installments on May 19, 2007, 2008, 2009 and 2010, subject to stockholder approval at the 2007 Annual Meeting.

Remarks:

	Stephen J. Sills, by Timothy J. Curry, attorney-in-fact	02/27/2007
	** 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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