FORM OF CHANGE OF CONTROL AGREEMENT

Exhibit 10(nn)

AGREEMENT

AGREEMENT by and between FLEET BOSTON CORPORATION, a Rhode Island corporation (the “Company”), and [    ] (the “Executive”), dated as of October 1, 1999.

WHEREAS, the Board of Directors of the Company (the “Board”) has determined that it is in the best interests of the Company and its stockholders to assure that the Company will have the continued dedication of the Executive, notwithstanding the possibility, threat or occurrence of a Change of Control (as defined in Section 2) of the Company. The Board believes it is imperative to diminish the inevitable distraction of the Executive by virtue of the personal uncertainties and risks created by a pending or threatened Change of Control and to encourage the Executive’s full attention and dedication to the Company currently and in the event of any threatened or pending Change of Control, and to provide the Executive with compensation and benefits arrangements upon a Change of Control which ensure that the compensation and benefits expectations of the Executive will be satisfied and which are competitive with those of other bank holding companies. Therefore, in order to accomplish these objectives, the Board caused the Company to enter into an Agreement with the Executive.

NOW, THEREFORE, IT IS HEREBY AGREED AS FOLLOWS:

1. Certain Definitions.

(a) The “Effective Date” shall be the first date during the “Change of Control Period” (as defined in Section 1(b)) on which a Change of Control occurs. Anything in this Agreement to the contrary notwithstanding, if the Executive’s employment with the Company is terminated or the Executive ceases to be an officer of the Company prior to the date on which a Change of Control occurs, and it is reasonably demonstrated that such termination of employment (1) was at the request of a third party who has taken steps reasonably calculated to effect the Change of Control or (2) otherwise arose in connection with or anticipation of the Change of Control, then for all purposes of this Agreement the “Effective Date” shall mean the date immediately prior to the date of such termination of employment.

(b) The “Change of Control Period” is the period commencing on the date hereof and ending on the earlier to occur of (x) the third anniversary of such date and (y) the Executive’s normal retirement under the Fleet Boston Corporation Pension Plan or similar BankBoston Plan in which the Executive is a participant (“Normal Retirement Date”); provided, however, that commencing on the date one year after the date hereof, and on each annual anniversary of such date (such date and each annual anniversary thereof is hereinafter referred to as the “Renewal Date”), the Change of Control Period shall be automatically extended without any further action by the Company or the Executive so as to terminate three years from such Renewal Date; provided, however, that if either the Company or the Executive shall give notice in writing to the other, 120 days prior to the Renewal Date, stating that the Change of Control Period shall not be extended, then the Change of Control Period shall expire three years from the date hereof, or if later, three years from the last effective Renewal Date.

2. Change of Control. For the purpose of this Agreement, a “Change of Control” shall mean:

(a) The acquisition, other than from the Company, by any individual, entity or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) of beneficial ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act) of 25% or more of the then outstanding shares of common stock of the Company (the “Outstanding Company Common Stock”); provided, however, that any acquisition by the Company or its subsidiaries, or any employee benefit plan (or related trust) of the Company or its subsidiaries, of 25% or more of the Outstanding Company Common Stock shall not constitute a Change of Control; and provided, further that any acquisition by a corporation with respect to which, following such acquisition, more than 50% of the then outstanding shares of common stock of such corporation is then beneficially owned, directly or indirectly, by all or substantially all of the individuals and entities who were the beneficial owners of the Outstanding Company Common Stock immediately prior to such acquisition in substantially the same proportion as their ownership immediately prior to such acquisition of the Outstanding Company Common Stock, shall not constitute a Change of Control; or

(b) Individuals who, as of the date of this Agreement, constitute the Board (the “Incumbent Board”) cease for any reason to constitute at least a majority of the Board, provided that any individual becoming a director subsequent to the date of this Agreement whose election, or nomination for election by the Company’s stockholders, was approved by a vote of at least a majority of the directors then comprising the Incumbent Board shall be considered as though such individual were a member of the Incumbent Board, but excluding, for this purpose, any such individual whose initial assumption of office is in connection with an actual or threatened election contest relating to the election of the Directors of the Company (as such terms are used in Rule 14a-11 of Regulation 14A promulgated under the Exchange Act); or

(c) Consummation of a reorganization, merger, consolidation, sale or other disposition of all or substantially all of the assets of the Company (a “Business Combination”), in each case, with respect to which all or substantially all of the individuals and entities who were the beneficial owners of the Outstanding Company Common Stock immediately prior to such Business Combination do not, following such Business Combination, beneficially own, directly or indirectly, more than 50% of the then outstanding shares of common stock of the corporation resulting from such a Business Combination (including, without limitation, a corporation which as a result of such transaction owns the Company or all or substantially all of the Company’s assets either directly or through one or more subsidiaries).

(d) Approval by the stockholders of the Company of a complete liquidation or dissolution of the Company.

Anything in this Agreement to the contrary notwithstanding, if an event that would, but for this paragraph, constitute a Change of Control results from or arises out of a purchase or other acquisition of the Company, directly or indirectly, by a corporation or other entity in which the Executive has a greater than ten percent (10%) direct or indirect equity interest, such event shall not constitute a Change of Control.

3. Employment Period. Subject to the terms and conditions hereof, the Company hereby agrees to continue the Executive in its employ, and the Executive hereby agrees to remain

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in the employ of the Company, for the period commencing on the Effective Date and ending on the earlier to occur of (x) the last day of the twenty-fourth month following the month in which the Effective Date occurs, and (y) the Executive’s Normal Retirement Date (the “Employment Period”).

4. Terms of Employment.

(a) Position and Duties.

(i) During the Employment Period, (A) the Executive’s position (including status, offices, titles and reporting requirements), authority, duties and responsibilities shall be at least commensurate in all material respects with the most significant of those held, exercised and assigned at any time during the 90-day period immediately preceding the Effective Date and (B) the Executive’s services shall be performed at the location where the Executive was employed immediately preceding the Effective Date or any office or location less than 35 miles from such location.

(ii) During the Employment Period, and excluding any periods of vacation and sick leave to which the Executive is entitled, the Executive agrees to devote reasonable attention and time during normal business hours to the business and affairs of the Company and, to the extent necessary to discharge the responsibilities assigned to the Executive hereunder, to use the Executive’s reasonable best efforts to perform faithfully and efficiently such responsibilities. During the Employment Period it shall not be a violation of this Agreement for the Executive to (A) serve on corporate, civic or charitable boards or committees, (B) deliver lectures, fulfill speaking engagements or teach at educational institutions and (C) manage personal investments, so long as such activities do not significantly interfere with the performance of the Executive’s responsibilities as an employee of the Company in accordance with this Agreement. It is expressly understood and agreed that to the extent that any such activities have been conducted by the Executive prior to the Effective Date, the continued conduct of such activities (or the conduct of activities similar in nature and scope thereto) subsequent to the Effective Date shall not thereafter be deemed to interfere with the performance of the Executive’s responsibilities to the Company.

(b) Compensation.

(i) Base Salary. During the Employment Period, the Executive shall receive an annual base salary (“Annual Base Salary”), which shall be paid at a bi-weekly rate, at least equal to twelve times the highest monthly base salary paid or payable to the Executive by the Company and its affiliated companies in respect of the twelve-month period immediately preceding the month in which the Effective Date occurs. During the Employment Period, the Annual Base Salary shall be reviewed at least annually and shall be increased at any time and from time to time as shall be substantially consistent with increases in base salary awarded in the ordinary course of business to other peer executives of the Company and its affiliated companies. Any increase in Annual Base Salary shall not serve to limit or reduce any other obligation to the Executive under this Agreement. Annual Base Salary shall not be reduced after any such increase and the term

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Annual Base Salary as utilized in this Agreement shall refer to Annual Base Salary as so increased. As used in this Agreement, the term “affiliated companies” includes any company controlled by, controlling or under common control with the Company.

(ii) Annual Bonus. In addition to Annual Base Salary, the Executive shall be awarded, for each fiscal year during the Employment Period, an annual bonus (the “Annual Bonus”) in cash at least equal to the average annualized (for any fiscal year consisting of less than twelve full months or with respect to which the Executive has been employed by the Company for less than twelve full months) bonus (the “Average Annual Bonus”) paid or payable to the Executive by the Company and its affiliated companies in respect of the three fiscal years immediately preceding the fiscal year in which the Effective Date occurs, or such shorter period of the Executive’s employment with the Company. Each such Annual Bonus shall be paid no later than the end of the third month of the fiscal year next following the fiscal year for which the Annual Bonus is awarded, unless the Executive shall elect to defer the receipt of such Annual Bonus pursuant to deferral plans of the Company.

(iii) Incentive, Savings and Retirement Plans. In addition to Annual Base Salary and Annual Bonus payable as hereinabove provided, the Executive shall be entitled to participate during the Employment Period in all incentive, savings and retirement plans, practices, policies and programs applicable to other peer executives of the Company and its affiliated companies, but in no event shall such plans, practices, policies and programs provide the Executive with incentive, savings and retirement benefits opportunities, in each case, less favorable, in the aggregate, than the most favorable of those provided by the Company and its affiliated companies for the Executive under such plans, practices, policies and programs as in effect at any time during the one-year period immediately preceding the Effective Date.

(iv) Welfare Benefit Plans. During the Employment Period, the Executive and/or the Executive’s family, as the case may be, shall be eligible for participation in and shall receive all benefits under welfare benefit plans, practices, policies and programs provided by the Company and its affiliated companies (including, without limitation, medical, prescription, dental, disability, salary continuance, employee life, group life, accidental death and travel accident insurance plans and programs) and applicable to other peer executives of the Company and its affiliated companies, but in no event shall such plans, practices, policies and programs provide benefits which are less favorable, in the aggregate, than the most favorable of such plans, practices, policies and programs in effect at any time during the one-year period immediately preceding the Effective Date.

(v) Expenses. During the Employment Period, the Executive shall be entitled to receive prompt reimbursement for all reasonable expenses incurred by the Executive in accordance with the most favorable policies, practices and procedures of the Company and its affiliated companies in effect at any time during the one-year period immediately preceding the Effective Date or, if more favorable to the Executive, as in effect at any time thereafter with respect to other peer executives of the Company and its affiliated companies.

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(vi) Fringe Benefits. During the Employment Period, the Executive shall be entitled to fringe benefits in accordance with the most favorable plans, practices, programs and policies of the Company and its affiliated companies in effect at any time during the one-year period immediately preceding the Effective Date or, if more favorable to the Executive, as in effect at any time thereafter with respect to other peer executives of the Company and its affiliated companies.

(vii) Office and Support Staff. During the Employment Period, the Executive shall be entitled to an office or offices of a size and with furnishings and other appointments, and to exclusive personal secretarial and other assistance, at least equal to the most favorable of the foregoing provided to the Executive by the Company and its affiliated companies at any time during the one-year period immediately preceding the Effective Date or, if more favorable to the Executive, as provided at any time thereafter with respect to other peer executives of the Company and its affiliated companies.

(viii) Vacation. During the Employment Period, the Executive shall be entitled to paid vacation in accordance with the most favorable plans, policies, programs and practices of the Company and its affiliated companies as in effect at any time during the one-year period immediately preceding the Effective Date or, if more favorable to the Executive, as in effect at any time thereafter with respect to other peer executives of the Company and its affiliated companies.

5. Termination of Employment.

(a) Death or Disability. The Executive’s employment shall terminate automatically upon the Executive’s death during the Employment Period. If the Company determines in good faith that the Disability of the Executive has occurred during the Employment Period (pursuant to the definition of “Disability” set forth below), it may give to the Executive written notice in accordance with Section 12(b) of this Agreement of its intention to terminate the Executive’s employment. In such event, the Executive’s employment with the Company shall terminate effective on the 30th day after receipt of such notice by the Executive (the “Disability Effective Date”), provided that, within the 30 days after such receipt, the Executive shall not have returned to full-time performance of the Executive’s duties. For purposes of this Agreement, “Disability” means the absence of the Executive from the Executive’s duties with the Company on a full-time basis for 180 consecutive business days as a result of incapacity due to mental or physical illness which is determined to be total and permanent by a physician selected by the Company or its insurers and acceptable to the Executive or the Executive’s legal representative (such agreement as to acceptability not to be withheld unreasonably).

(b) Cause. The Company may terminate the Executive’s employment during the Employment Period for “Cause”. For purposes of this Agreement, “Cause” means (i) an act or acts of personal dishonesty taken by the Executive and intended to result in substantial personal enrichment of the Executive at the expense of the Company, (ii) repeated violations by the Executive of the Executive’s obligations under Section 4(a) of this Agreement which are demonstrably willful and deliberate on the Executive’s part and which are not remedied in a

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reasonable period of time after receipt of written notice from the Company or (iii) the conviction of the Executive of a felony involving moral turpitude.

(c) Good Reason. The Executive’s employment may be terminated during the Employment Period by the Executive for Good Reason. For purposes of this Agreement, “Good Reason” means:

(i) the assignment to the Executive of any duties inconsistent in any respect with the Executive’s position (including status, offices, titles and reporting requirements), authority, duties or responsibilities as contemplated by Section 4(a) of this Agreement, or any other action by the Company which results in a diminution in such position, authority, duties or responsibilities, excluding for this purpose an isolated, insubstantial and inadvertent action not taken in bad faith and which is remedied by the Company promptly after receipt of notice thereof given by the Executive;

(ii) any failure by the Company to comply with any of the provisions of Section 4(b) of this Agreement, other than an isolated, insubstantial and inadvertent failure not occurring in bad faith and which is remedied by the Company promptly after receipt of notice thereof given by the Executive;

(iii) the Company’s requiring the Executive to be based at any office or location other than that described in Section 4(a)(i)(B) hereof;