THE HANOVER INSURANCE GROUP, INC. 2006 LONG-TERM INCENTIVE PLAN RESTRICTED STOCK UNIT AGREEMENT

Exhibit 10.40

THE HANOVER INSURANCE GROUP, INC.

2006 LONG-TERM INCENTIVE PLAN

RESTRICTED STOCK UNIT AGREEMENT

This Restricted Stock Unit Agreement (the “Agreement”) is effective as of <GRANT DATE> (the “Grant Date”) by and between The Hanover Insurance Group, Inc., a Delaware corporation (the “Company”), and <PARTICIPANT NAME> (the “Participant” or “you”). Capitalized terms used without definition herein shall have the meanings set forth in The Hanover Insurance Group, Inc. 2006 Long-Term Incentive Plan (the “Plan”).

P R E A M B L E

WHEREAS, pursuant to the Plan and subject to the terms of this Agreement, the Administrator has agreed to grant to the Participant an Award of restricted stock units (the “RSUs”).

NOW, THEREFORE, for and in consideration of the foregoing and the mutual covenants and promises hereinafter set forth, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

As soon as reasonably practicable following vesting of the RSUs, but in no event later than 60 days following vesting, the Company shall make delivery of the Shares. In the event the Vesting Date falls on a non-business day (weekend or holiday on which banks are not generally open in the Commonwealth of Massachusetts), the Vesting Date shall be the next following business day.

If, prior to the expiration of the LTD Extension Period, Participant is removed from LTD Status and immediately thereafter returns to active Employment with THG, Participant shall be treated (for the purposes of this Agreement) as if he/she were never placed in LTD Status and remained an active Employee of THG, shall be given credit toward vesting for the period Participant was in LTD Status and this Agreement shall remain in full force and effect in accordance with its terms.

(a) Except as provided below in Section 6(b), in the event of a Change in Control the Participant shall automatically vest in 100% of the RSUs.

(b) Notwithstanding Section 6(a), no acceleration of vesting shall occur with respect to the RSUs if the Administrator reasonably determines in good faith prior to the occurrence of a Change in Control that this Award of RSUs shall be honored or assumed, or new rights substituted therefor (such honored, assumed or substituted award hereinafter called an “Alternative Award”), by Participant’s employer (or the parent or a subsidiary of such employer) immediately following the Change in Control, provided that any such Alternative Award must:

(i) be based on stock which is traded, or will be traded upon consummation of the Change in Control, on an established securities market;

(ii) provide such Participant (or each Participant in a class of Participants) with rights and entitlements substantially equivalent to or better than the rights, terms and conditions applicable under this Award, including, but not limited to, an identical or better vesting schedule;

(iii) have substantially equivalent economic value to this Award (determined at the time of the Change in Control); and

(iv) have terms and conditions which provide that in the event that the Participant’s employment is involuntarily terminated (other than for Cause) or Participant terminates employment for “Good Reason” (as defined below) prior to the Vesting Date, the Participant shall automatically vest in 100% of the Alternative Award and any conditions on a Participant’s rights under, or any restrictions on transfer or exercisability applicable to, the vested portion of such Alternative Award shall be waived or shall lapse.

For this purpose, “Good Reason” shall mean the occurrence of one or more of the events listed below following a Change in Control:

(x) to the extent you are a “Participant” (as that term is defined in the CIC Plan) in the Company’s Amended and Restated Employment Continuity Plan or its successor plan (the “CIC Plan”), the occurrence of any of the events enumerated under the definition of “Good Reason” applicable to Participant’s “Tier” level as set forth in the CIC Plan; or

(y) if you are not a “Participant” in the CIC Plan, the occurrence of any of the following (A) a reduction in your rate of annual base salary as in effect immediately prior to such Change in Control; (B) a reduction in your annual short-term incentive compensation plan target award (but excluding the conversion of any cash incentive arrangement into an equity incentive

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arrangement of commensurate value or vice versa) from that which was in effect immediately prior to such Change in Control; or (C) any requirement that you relocate to an office more than 35 miles from the facility where you were located immediately prior to the Change in Control.

(c) In the event a Participant believes that a “Good Reason” event has been triggered, the Participant must give the Company written notice within 30 days of the occurrence of such triggering event and a proposed termination date which shall be not sooner than 60 days nor later than 90 days after the date of such notice. Such notice shall specify the Participant’s basis for determining that “Good Reason” has been triggered. The Company shall have the right to cure a purported “Good Reason” within 30 days of receipt of said notice

(d) Notwithstanding Sections 6(a) and (b) above, the Administrator may elect, in its sole discretion, exercised prior to the effective date of the Change in Control, to accelerate all, or a greater percentage of the RSUs, than is otherwise required pursuant to the terms of this Section 6.

(a) The Participant hereby acknowledges and agrees that in the event of any breach of Section 9 of this Agreement, the Company would be irreparably harmed and could not be made whole by monetary damages. The Participant accordingly agrees to waive the defense in any action for injunctive relief or specific performance that a remedy at law would be adequate and that the Company, in addition to any other remedy to which it may be entitled at law or in equity, shall be entitled to an injunction or to compel specific performance of Section 9.

(b) In addition to any other remedy to which the Company may be entitled at law or in equity (including the remedy provided in the preceding paragraph), the Participant hereby acknowledges and agrees that in the event of any breach of Section 9 of this Agreement, Participant shall be required to refund to the Company the value received by Participant upon vesting of the RSUs; provided, however, that the Company makes any such claim, in writing, against Participant alleging a violation of Section 9 not later than two years following your termination of employment with the Company.

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The Company makes no representations to Participant with respect to the tax treatment of any amount paid or payable pursuant to this Award. While this Award is intended to be interpreted and operated to the extent possible so that any such amounts shall be exempt from the requirements of Section 409A of the Internal Revenue Code (“Section 409A”), in no event shall the Company be liable to Participant for or with respect to any taxes, penalties and/or interest which may be imposed upon any such amounts pursuant to Section 409A or any other federal or state tax law. To the extent that any such amount should be subject to Section 409A (or any other federal or state tax law), the Participant shall bear the entire risk of any such taxes, penalties and or interest.

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IN WITNESS WHEREOF, the parties hereto have entered into this Agreement as of the Grant Date.

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