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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934
(Amendment No. 1)*

TOWER GROUP, INC.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

89177104

(CUSIP Number)

December 31, 2005

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

     o Rule 13d-1(b)

     þ Rule 13d-1(c)

     o 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).

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

CUSIP No. 89177104 

1	NAMES OF REPORTING PERSONS: HCC Insurance Holdings, Inc.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   o
	(b)   þ
3	SEC USE ONLY:
4	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Delaware
		5	SOLE VOTING POWER:
NUMBER OF			0
SHARES		6	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			1,180,108
EACH		7	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			0
WITH:		8	SHARED DISPOSITIVE POWER:
			1,180,108
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	1,180,108
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9):
	5.97%
12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	HC

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Item 1.
(a)	Name of Issuer
	Tower Group, Inc.
(b)	Address of Issuer’s Principal Executive Offices
	120 Broadway, 14th Floor
	New York, NY 10271
Item 2.
(a)	Name of Person Filing
	HCC Insurance Holdings, Inc.
(b)	Address of Principal Business Office
	13403 Northwest Freeway
	Houston, Texas 77040-6094
(c)	Citizenship
	Delaware
(d)	Title of Class of Securities
	Common Stock
(e)	CUSIP Number
	89177104
Item 3.	If this statement is filed pursuant §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	o	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).
(b)	o	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
(c)	o	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).
(d)	o	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).
(e)	o	An investment advisor in accordance with §240.13d-1(b)(1)(ii)(E);
(f)	o	An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);
(g)	o	A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);
(h)	o	A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	o	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)	o	Group, in accordance with §240.13d-1(b)(1)(ii)(J).

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Item 4.		Ownership.
(a)		Amount beneficially owned:
		1,180,108
(b)		Percent of class:
		5.97%
(c)		Number of shares as to which the person has:
		(i)	Sole power to vote or to direct the vote: 0
		(ii)	Shared power to vote or to direct the vote: 1,180,108
		(iii)	Sole power to dispose or to direct the disposition of: 0
		(iv)	Shared power to dispose or to direct the disposition of: 1,180,108
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 5% of the class of securities, check the following: o
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 or Control Person.
		See Exhibit A for the identity of the subsidiaries which directly beneficially own the securities reported herein.
Item 8.		Identification and Classification of Members of the Group.
		Not applicable.
Item 9.		Notice of Dissolution of Group.
		Not applicable.
Item 10.		Certifications
		By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

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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.

Date: February 14, 2006

By:	/s/ Christopher L. Martin
	Christopher L. Martin,
	Executive Vice President

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EXHIBIT INDEX

Exhibit A	Information Required by Item 7
Exhibit B	Joint Filing Agreement between HCC Insurance Holdings, Inc. and Houston Casualty Company

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