STOCK PURCHASE AGREEMENT

Exhibit 10.1

EXECUTION COPY

STOCK PURCHASE AGREEMENT

By and Among

BOSTON PRIVATE FINANCIAL HOLDINGS, INC.

GIBRALTAR PRIVATE BANK & TRUST COMPANY

and

THE BUYERS set forth on Exhibit A hereto

Dated as of September 17, 2009

TABLE OF CONTENTS

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Exhibit A – Buyers

Exhibit B – Form of Federal Stock Charter of Gibraltar Private Bank & Trust Company

Exhibit C – Form of Bylaws of Gibraltar Private Bank & Trust Company

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STOCK PURCHASE AGREEMENT

THIS STOCK PURCHASE AGREEMENT (this “ Agreement ”), is effective as of September 17, 2009, by and among BOSTON PRIVATE FINANCIAL HOLDINGS, INC. , a Massachusetts corporation (“ Seller ”), GIBRALTAR PRIVATE BANK & TRUST COMPANY , a federally-chartered stock savings association (the “ Bank ”), and the buyers listed on Exhibit A hereto (the “ Buyers ”). The capitalized terms used in this Agreement, unless otherwise defined herein, are defined in Section 6.13.

WHEREAS , Seller owns beneficially and of record all of the issued and outstanding capital stock (the “ Shares ”) of the Bank; and

WHEREAS , Seller desires to sell to the Buyers, and the Buyers desire to purchase from Seller, the Shares on the terms and conditions set forth in this Agreement.

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and agreements set forth herein, the parties hereto agree as follows:

ARTICLE I - THE PURCHASE AND SALE

1.1 Purchase and Sale of the Shares . Subject to the terms and conditions set forth in this Agreement, at the Closing, Seller shall sell, assign, transfer, convey and deliver the Shares to the Buyers, and the Buyers shall purchase and acquire from Seller, all right, title and interest in, to and under the Shares from Seller, free and clear of any lien, claim, option, mortgage, pledge, security interest, charge, encumbrance or other restriction of any nature whatsoever (each, a “ Lien ”) or right or claim of others.

1.2 Cash Purchase Price . In full consideration of the Buyers’ purchase of the Shares, the Buyers shall pay to Seller a cash purchase price in an aggregate amount equal to ninety-three million dollars ($93,000,000) (the “ Purchase Price ”).

1.3 Closing . The closing of the sale and purchase of the Shares pursuant to this Article I (the “ Closing ”) will take place on the date hereof (the “ Closing Date ”).

1.4 Deliveries at Closing .

(a) At the Closing, Seller will deliver or cause to be delivered to the Buyers the following:

(i) free and clear of any Liens or rights or claims of others, stock certificates evidencing the Shares in an amount with respect to each Buyer as set forth opposite such Buyer’s name on Exhibit A hereto, in each case duly endorsed in blank or accompanied by stock powers duly executed in blank, or if such stock certificates are not then available, affidavits of loss in lieu thereof;

(ii) a duly executed certificate of the secretary of Seller, dated the Closing Date, certifying (A) attached resolutions of its board with respect to the transactions contemplated or otherwise to be effected by it at the Closing and (B) the incumbency of its officers; and

(iii) duly executed certificate of non-foreign status of Seller, substantially in the form of the sample certification contained in Treasury Regulation Section 1.1445-2(b)(2)(iv)(B).

(b) At the Closing, the Buyers will deliver or cause to be delivered to Seller the Purchase Price, which shall be delivered to Seller by wire transfer of immediately available funds to an account designated by Seller.

ARTICLE II - REPRESENTATIONS AND WARRANTIES OF THE BUYERS

Except as set forth in the Buyers Disclosure Schedules (it being agreed that disclosure in any section of the Buyers Disclosure Schedules shall apply only to the indicated section of this Agreement, except to the extent that it is reasonably apparent on the face of the disclosure that such disclosure is relevant to another section of this Agreement), each Buyer, severally and not jointly, represents and warrants to Seller and the Bank as follows:

2.1 Authorization . Such Buyer has the legal capacity, power and authority to execute and deliver this Agreement and each other agreement, document or instrument contemplated by this Agreement and to perform such Buyer’s obligations hereunder and thereunder. All actions or proceedings to be taken by or on the part of such Buyer to authorize and permit the execution and delivery by such Buyer of this Agreement and the instruments required to be executed and delivered by him, her or it pursuant hereto, the performance by such Buyer of such Buyer’s obligations hereunder and the consummation by such Buyer of the transactions contemplated hereby, have been duly and properly taken. This Agreement has been duly executed and delivered by such Buyer and, assuming the due authorization, execution and delivery of this Agreement by Seller, the Bank and each of the other Buyers, this Agreement constitutes the legal, valid and binding obligation of the Buyer, enforceable against such Buyer in accordance with its terms, except as such enforceability may be limited by bankruptcy, insolvency, moratorium, reorganization and other similar Laws affecting creditors’ rights generally and by general equity principles.

2.2 No Violation or Approval .

(a) Neither the execution, delivery and performance of this Agreement and the other agreements, documents and instruments contemplated hereby by such Buyer, nor the consummation by such Buyer of the transactions contemplated hereby in accordance with the terms hereof and thereof, will (i) violate, conflict with or result in a breach of any provisions of, or constitute a default (or an event that, with notice or lapse of time or both, would constitute a default) under, or result in the termination of, or accelerate the performance required by, or result in a right of termination or acceleration under, or the creation of any Lien upon, any of the properties or assets of such Buyer, under any of the terms, conditions or provisions of (A) if such Buyer is not a natural

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person, the organizational documents or by-laws of such Buyer, or (B) any note, bond, mortgage, indenture, deed of trust, license, lease, agreement or other instrument or obligation to which the Buyer is a party or by which such Buyer may be bound, or to which such Buyer or the properties or assets of such Buyer may be subject, in the case of the foregoing clause (B) only, which violation, conflict, breach, default or termination or acceleration is reasonably likely to have, individually or in the aggregate, a Material Adverse Effect, or (ii) assuming compliance with the matters referred to in Section 2.2(b) below, violate any judgment, ruling, order, writ, injunction, decree, statute, rule or regulation of any Governmental Body or self-regulatory authority applicable to such Buyer, which violation is reasonably likely to have, individually or in the aggregate, a Material Adverse Effect.

(b) No notices to, filings with, authorizations of, exemptions by, or consents or approvals of any Governmental Body or other Persons are necessary for the consummation by such Buyer of the transactions contemplated by this Agreement, except where failure to make such notices or filings or obtain such authorizations, exemptions, consents, approvals, or actions would not have, individually or in the aggregate, a Material Adverse Effect.

2.3 Brokers and Finders . Such Buyer has not employed any broker or finder or incurred any liability for any financial advisory fees, brokerage fees, commissions or finder’s fees that are or would become, at or following the Closing, obligations of the Seller or the Bank, except for fees and commissions incurred in connection with the engagement of Sandler O’Neill + Partners, L.P. and for legal fees payable to Wachtell, Lipton, Rosen & Katz in connection with the transactions contemplated by this Agreement, all of which will be paid by the Bank following the Closing. Such Buyer shall be responsible for any other fees or expenses incurred by such Buyer in connection with such Buyer’s entering into this Agreement and participation in the transactions contemplated hereby.

2.4 Private Placement . Such Buyer understands and acknowledges that the Shares being sold and issued pursuant to this Agreement are being offered without an offering circular filed with, and declared effective by, the OTS pursuant to an exemption from such requirements provided for by Section 563g.4 of Part 563g of the regulations promulgated by the OTS (the “ OTS Regulations ”), and are exempt from the registration requirements of the Securities Act and the registration or qualification requirements of state securities or “blue sky” laws.

2.5 Limitations on Transfer . Such Buyer understands and agrees that (a) the Shares cannot be offered, resold or otherwise transferred except pursuant to an applicable exemption from registration under the OTS Regulations and the applicable securities laws of any other jurisdiction, and (b) due care should be taken by the Buyer in any sale of the Shares to ensure that Buyer is not an underwriter within the meaning of Section 563g.1(a)(14) of Part 563g of the OTS Regulations. Such Buyer hereby covenants and agrees that such Buyer will not offer, sell or otherwise transfer any of the Shares except in compliance with applicable federal and state regulatory, securities and “blue sky” laws.

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2.6 Restrictive Legends . The certificates representing the Shares shall bear, in addition to any other legends required under applicable state securities or “blue sky” laws, a legend in substantially the following form:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN AND WILL NOT BE REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”) OR THE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION AND WERE NOT OFFERED BY AN OFFERING CIRCULAR FILED WITH, AND DECLARED EFFECTIVE BY, THE OFFICE OF THRIFT SUPERVISION (THE “OTS”) PURSUANT TO SECTION 563G.2 OF PART 563G OF THE REGULATIONS PROMULGATED BY THE OTS (THE “OTS REGULATIONS”), BUT INSTEAD WERE SOLD IN RELIANCE UPON AN EXEMPTION FROM THE OFFERING CIRCULAR REQUIREMENT PROVIDED FOR BY SECTION 563G.4 OF PART 563G OF THE OTS REGULATIONS AND ARE EXEMPT FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT. THE SHARES MAY BE TRANSFERRED ONLY PURSUANT TO AN APPLICABLE EXEMPTION FROM REGISTRATION UNDER THE OTS REGULATIONS, THE SECURITIES ACT, AND THE APPLICABLE SECURITIES LAWS OF ANY OTHER JURISDICTION. DUE CARE SHOULD BE TAKEN BY A HOLDER IN ANY SALE OF THE SHARES TO ENSURE THAT SUCH HOLDER IS NOT AN UNDERWRITER WITHIN THE MEANING OF SECTION 563G.1(A)(14) OF PART 563G OF THE OTS REGULATIONS.”

In order to prevent any transfer from taking place in violation of applicable law or the terms of this Agreement, the Bank may cause a stop transfer order to be placed with its transfer agent with respect to any Shares. The Bank will not be required to transfer on its books any Shares that have been sold or transferred in violation of any provision of applicable law.

2.7 Accredited Investor . Such Buyer is an “accredited investor” within the meaning of Rule 501(a) of Regulation D under the Securities Act, as presently in effect.

2.8 Investment Intent . Such Buyer is acquiring the Shares for such Buyer’s own account (and not for the account of others) for investment purposes and not with a view to, or for offer or sale in connection with, any distribution. Such Buyer understands that there is no established market for the Shares and that a market for the Shares may not develop and that no federal or state agency has passed upon the Shares, or made any findings or determination as to the fairness of an investment in the Shares.

2.9 Investment Experience and Status . Such Buyer has such knowledge and experience in financial and business matters that such Buyer is capable of evaluating the merits and risks of an investment in the Shares and protecting such Buyer’s own interests in connection with such investment.

2.10 Documents Delivered; Information . Such Buyer acknowledges that such Buyer has received a copy of this Agreement and been afforded the opportunity to review the schedules and exhibits hereto. Such Buyer has received or has had access to all the information relating to the Bank that such Buyer has requested and considers necessary and relevant to making an

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informed investment decision with respect to the Shares. Such Buyer has been given the opportunity to make a thorough investigation of the activities of the Bank and has been furnished with access to materials relating to the Bank and its activities. Such Buyer has been afforded the opportunity to obtain any additional information deemed necessary by such Buyer to verify the accuracy of the information conveyed to such Buyer. Such Buyer acknowledges and agrees that except as set forth in Article III and Article IV hereof, neither the Seller nor the Bank has made any representations or warranties to the undersigned whatsoever about the Bank, its business or prospects or any other matter in connection with the undersigned’s investment in the Bank and such Buyer is not relying on any information, including any information statements, presentations or written or oral statements, relating to the Bank supplied by Seller, the Bank or any Person authorized by Seller or the Bank.

2.11 Professional Advice . With respect to the legal, tax, accounting, financial and other economic considerations involved in acquiring the Shares, such Buyer is not relying on Seller, the Bank, or any other Buyer, or any director, officer, employee, agent or other Representative of any of the foregoing.

2.12 Further Representations by Foreign Company Buyers . If such Buyer is not a United States person, such Buyer hereby represents that such Buyer is satisfied as to the full observance of the laws of such Buyer’s jurisdiction in connection with acquiring any Shares and the execution and delivery by such Buyer of this Agreement and any other instrument or document executed and delivered by such Buyer pursuant hereto, including (a) the legal requirements within such Buyer’s jurisdiction for acquiring any of the Shares, (b) any foreign exchange restrictions applicable to any such acquisition of the Shares, (c) any governmental or other consents that may need to be obtained, and (d) the income tax and other tax consequences, if any, that may be relevant to the purchase, holding, redemption, sale, or transfer of any of the Shares.

2.13 No Affiliations . Such Buyer is not an affiliate of any other Buyer. The decision of such Buyer to invest in the Bank has been reached independently from other Buyers, Seller, the Bank or any of their respective affiliates or agents. Such Buyer is not, to such Buyer’s knowledge, managed or advised by an investment manager or investment advisor who performs the same services for other Buyers and has not been advised by Seller, the Bank or any of their respective Affiliates. Such Buyer has not engaged and will not engage as part of a group consisting of substantially the same entities as other Buyers, in substantially the same combination of interests, in any additional banking or nonbanking activities or business ventures in the United States. Such Buyer is not a party to any agreements or understandings between any Buyers (a) for the purpose of controlling the Bank or any of its Subsidiaries or (b) to act in concert in respect of the Bank or any of its Subsidiaries. Such Buyer is not a party to any agreements or understandings pursuant to which it has the right to acquire the Shares of any other Buyer.

2.14 Commonly Controlled Insured Depository Institutions . Such Buyer has not taken, permitted or allowed any action that would cause the Bank or any Subsidiary of the Bank to become a “commonly controlled insured depository institution” (as that term is defined and interpreted for purposes of 12 U.S.C. § 1815(e), as may be amended or supplemented from time to time, and any successor thereto) with respect to any institution that is not a direct or indirect

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Subsidiary of the Bank and such Buyer agrees not to take, permit or allow any such action. In the event that such Buyer believes that it is reasonably likely to breach such obligation, such Buyer shall immediately notify the Bank, and shall cooperate in good faith with the board of directors of the Bank promptly to modify any ownership or other arrangements or take any other action, in each case, as is necessary to cure or avoid such breach.

ARTICLE III - REPRESENTATIONS AND WARRANTIES OF THE BANK

The Bank represents and warrants to the Buyers as follows:

3.1 Organization . The Bank is a federally-chartered savings bank duly organized, validly existing and in good standing under the laws of the United States of America. The Bank’s deposits are insured by the FDIC in the manner and to the fullest extent provided by applicable Law, and all premiums and assessments required to be paid in connection therewith have been paid by the Bank when due. The Bank has made available to the Buyers a true, complete and correct copy of each of the Bank’s organizational documents, each as in effect on the date hereof. The Bank has all requisite power and authority to own, operate, lease and encumber its properties and carry on its business as currently conducted, and is duly licensed or qualified to do business in each jurisdiction in which the nature of the business conducted by it or the character or location of the properties and assets owned or leased by it makes such licensing or qualification necessary.

3.2 Authorization . The Bank has the corporate capacity, power and authority to execute and deliver this Agreement and each other agreement, document or instrument contemplated by this Agreement and to perform its obligations hereunder and thereunder. All actions or proceedings to be taken by or on the part of the Bank to authorize and permit the execution and delivery by it of this Agreement and the instruments required to be executed and delivered by it pursuant hereto, the performance by the Bank of its respective obligations hereunder and the consummation by the Bank of the transactions contemplated hereby, have been duly and properly taken. No other corporate proceedings on the part of the Bank are necessary to approve this Agreement and to consummate the transactions contemplated hereby. This Agreement has been duly and validly executed and delivered by the Bank and, assuming the due authorization, execution and delivery of this Agreement by Seller and the Buyers, this Agreement constitutes the legal, valid and binding obligation of the Bank, enforceable against the Bank in accordance with its terms, except as such enforceability may be limited by bankruptcy, insolvency, moratorium, reorganization and other similar Laws affecting creditors’ rights generally and by general equity principles.

3.3 No Violation or Approval .

(a) Neither the execution, delivery and performance of this Agreement and the other agreements, documents and instruments contemplated hereby by the Bank, nor the consummation by the Bank of the transactions contemplated hereby in accordance with the terms hereof and thereof, will (i) violate, conflict with or result in a breach of any provisions of, or constitute a default (or an event that, with notice or lapse of time or both, would constitute a default) under, or result in the termination of, or accelerate the performance required by, or result in a right of termination or acceleration under, or the

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creation of any Lien upon, any of the properties or assets of the Bank under any of the terms, conditions or provisions of, (A) the organizational documents or by-laws of the Bank, or (B) any note, bond, mortgage, indenture, deed of trust, license, lease, agreement or other instrument or obligation to which the Bank is a party or by which the Bank may be bound, or to which the Bank or the properties or assets of the Bank may be subject, in the case of the foregoing clause (B) only, which violation, conflict, breach, default or termination or acceleration is reasonably likely to have, individually or in the aggregate, a Material Adverse Effect, or (ii) assuming compliance with the matters referred to in Section 3.3(b) below, violate any judgment, ruling, order, writ, injunction, decree, statute, rule or regulation of any Governmental Body or self-regulatory authority applicable to the Bank, which violation is reasonably likely to have, individually or in the aggregate, a Material Adverse Effect.

(b) No notices to, filings with, authorizations of, exemptions by, or consents or approvals of any Governmental Body or other Persons are necessary for the consummation by the Bank of the transactions contemplated by this Agreement, except where failure to make such notices or filings or obtain such authorizations, exemptions, consents, approvals, or actions would not have, individually or in the aggregate, a Material Adverse Effect.

3.4 Taxes . Except as are not, individually or in the aggregate, reasonably likely to have a Material Adverse Effect or as otherwise set forth in Section 3.4 of the Seller Disclosure Schedule:

(a) All Tax Returns that are required to be filed after the Original Acquisition Date by or on behalf of the Bank or any of its Subsidiaries (or by or with respect to any consolidated, combined, unitary or affiliated group of which any of them is or has been a member) have been timely filed (taking into account any extension of time to file granted or obtained).

(b) Neither the Bank nor any of its Subsidiaries (nor any consolidated, combined, unitary or affiliated group of which any of them is or has been a member after the Original Acquisition Date) has agreed to any extension or waiver of the statute of limitations applicable to any Tax Return referred to in clause (a) of this Section 3.4 or agreed to any extension of time with respect to a Tax assessment or deficiency, which period (after giving effect to such extension or waiver) has not yet expired.

(c) There is not pending or threatened in writing any audit, examination, investigation or other proceeding with respect to Taxes of the Bank or any of its Subsidiaries (including any such Taxes reportable on a consolidated, combined, or unitary Tax Return filed after the Original Acquisition Date), and during the past three years, no claim has been made in writing by any Taxing Authority in a jurisdiction where the Bank or a Subsidiary does not file Tax Returns to the effect that the Bank or such Subsidiary may be subject to taxation in that jurisdiction.

(d) Neither the Bank nor any of its Subsidiaries is subject to any closing agreement pursuant to Section 7121 of the Code or any predecessor provision thereof, or any

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corresponding or similar provision of state, local or foreign Law, or is subject to, or has pending any request for, any private letter ruling, technical advice or permission for any change in accounting methods, in all cases, that is applicable to any periods after the Closing Date.

(e) Neither the Bank nor any of its Subsidiaries has been a party to any distribution occurring during the three-year period prior to the date of this Agreement, or otherwise as part of a plan (or series of related transactions) of which this transaction is a part, in which the parties to such distribution treated the distribution as one to which Section 355 of the Code applied.

ARTICLE IV - REPRESENTATIONS AND WARRANTIES OF SELLER

Except as set forth in the Seller Disclosure Schedules (it being agreed that disclosure in any section of the Seller Disclosure Schedules shall apply only to the indicated section of this Agreement, except to the extent that it is reasonably apparent on the face of the disclosure that such disclosure is relevant to another section of this Agreement), Seller hereby represents and warrants to the Buyers and the Bank as follows:

4.1 Organization . Seller is a corporation duly organized, validly existing and in good standing under the laws of The Commonwealth of Massachusetts. Seller is duly registered as a bank holding company under the Bank Holding Company Act of 1956, as amended, and meets the applicable requirements for qualification as such. Seller has all requisite power and authority to own, operate, lease and encumber its properties and carry on its business as currently conducted, and is duly licensed or qualified to do business in each jurisdiction in which the nature of the business conducted by it or the character or location of the properties and assets owned or leased by it makes such licensing or qualification necessary.

4.2 Authorization . Seller has the corporate capacity, power and authority to execute and deliver this Agreement and each other agreement, document or instrument contemplated by this Agreement and to perform its obligations hereunder and thereunder. All actions or proceedings to be taken by or on the part of Seller (including in its capacity as the Bank’s sole shareholder) to authorize and permit the execution and delivery by it of this Agreement and the instruments required to be executed and delivered by it pursuant hereto, the performance by Seller of its respective obligations hereunder and the consummation by Seller of the transactions contemplated hereby, have been duly and properly taken. No other corporate proceedings (including any approvals of Seller’s stockholders) on the part of Seller are necessary to approve this Agreement and to consummate the transactions contemplated hereby. This Agreement has been duly and validly executed and delivered by Seller and, assuming the due authorization, execution and delivery of this Agreement by the Bank and the Buyers, this Agreement constitutes the legal, valid and binding obligation of Seller, enforceable against Seller in accordance with its terms, except as such enforceability may be limited by bankruptcy, insolvency, moratorium, reorganization and other similar Laws affecting creditors’ rights generally and by general equity principles.

4.3 Capitalization of the Bank . As of the date of this Agreement, the authorized, issued and outstanding capital stock of the Bank is set forth on Section 4.3 of the Seller

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Disclosure Schedule. All of the issued and outstanding shares of capital stock of the Bank are duly authorized, validly issued, fully paid, nonassessable and free of preemptive rights. Seller, by action of its board of directors or officers, has not entered into or granted any outstanding subscriptions, options, warrants, puts, calls, rights, exchangeable or convertible securities or other commitments or agreements of any character relating to the issued or unissued capital stock or other securities or ownership or equity interests of the Bank or any Subsidiary of the Bank, or otherwise obligating the Bank or any Subsidiary of the Bank to issue, transfer, sell, purchase, redeem or otherwise acquire any such stock, securities or interests. Seller owns all of the outstanding shares of capital stock of the Bank free and clear of all Liens, rights of first refusal, agreements, limitations on Seller’s voting rights, and other encumbrances of any nature whatsoever. Seller, by action of its board of directors or officers, has not caused the Bank to become subject to any obligation by reason of any agreement to register the offer and sale or resale of any of its securities under applicable OTS Regulations.

4.4 No Violation or Approval .

(a) Neither the execution, delivery and performance of this Agreement and the other agreements, documents and instruments contemplated hereby by Seller, nor the consummation by Seller of the transactions contemplated hereby in accordance with the terms hereof and thereof, will (i) violate, conflict with or result in a breach of any provisions of, or constitute a default (or an event that, with notice or lapse of time or both, would constitute a default) under, or result in the termination of, or accelerate the performance required by, or result in a right of termination or acceleration under, or the creation of any Lien upon, any of the properties or assets of Seller, under any of the terms, conditions or provisions of (A) the organizational documents or by-laws of Seller, or (B) any note, bond, mortgage, indenture, deed of trust, license, lease, agreement or other instrument or obligation to which Seller is a party or by which Seller may be bound, or to which Seller or the properties or assets of Seller may be subject, in the case of the foregoing clause (B) only, which violation, conflict, breach, default or termination or acceleration is reasonably likely to have, individually or in the aggregate, a Material Adverse Effect, or (ii) assuming compliance with the matters referred to in Section 4.4(b) below, violate any judgment, ruling, order, writ, injunction, decree, statute, rule or regulation of any Governmental Body or self-regulatory authority applicable to Seller, which violation is reasonably likely to have, individually or in the aggregate, a Material Adverse Effect.

(b) No notices to, filings with, authorizations of, exemptions by, or consents or approvals of any Governmental Body or other Persons are necessary for the consummation by Seller of the transactions contemplated by this Agreement, except where failure to make such notices or filings or obtain such authorizations, exemptions, consents, approvals, or actions would not have, individually or in the aggregate, a Material Adverse Effect.

4.5 Brokers and Finders . Neither Seller nor any of its officers, directors or employees has employed any broker or finder or incurred any liability for any financial advisory fees, brokerage fees, commissions or finder’s fees, except for fees and commissions incurred in connection with the engagement of Goldman, Sachs & Co. and for legal, accounting and other professional fees payable in connection with the transactions contemplated by this Agreement. Seller shall be responsible for the payment of all such fees.

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ARTICLE V - ADDITIONAL AGREEMENTS

5.1 Directors’ and Officers’ Indemnification and Insurance .

(a) As of the Closing Date, the Bank has purchased a “tail” directors’ and officers’ liability insurance policy (which by its terms shall survive the Closing) for its directors and officers, which provides such directors and officers with coverage for six (6) years following the Closing Date of not less than the existing coverage under, and has other terms not materially less favorable on the whole to the insured persons than, the directors’ and officers’ liability insurance coverage presently maintained by the Bank prior to the Closing. The Bank shall maintain such policy in full force and effect and continue to honor the obligations thereunder. In the event the Bank or any of its successors or assigns (i) consolidates with or merges into any other Person and shall not be the continuing or surviving corporation or entity of such consolidation or merger, or (ii) transfers or conveys all or substantially all of its properties and assets to any Person, then, and in each such case, to the extent necessary, proper provision shall be made so that the successors and assigns of the Bank assume the obligations set forth in this Section 5.1. Subject to applicable Laws, Seller and the Bank agree that all rights to indemnification or exculpation existing in favor of, and all limitations on the personal liability of, each present and former director and officer of the Bank and/or any Subsidiaries of the Bank on or prior to the Closing provided for in the Bank’s charter and by-laws or otherwise in effect as of the date hereof shall continue in full force and effect in all material respects for a period of six (6) years from the Closing; provided, however, that all rights to indemnification in respect of any claims asserted or made within such period shall continue until the disposition of such claim.

(b) The provisions of this Section 5.1 are intended to be for the benefit of, and enforceable by, each Indemnified Party and his or her heirs and representatives, and nothing herein shall affect any indemnification rights that any Indemnified Party and his or her heirs and representatives may have under the charter and by-laws of the Bank, any contract or applicable Law.

5.2 Employees .

(a) Following the Closing Date, the Bank shall honor (i) all Bank Employment Agreements as may be in effect as of the Closing Date between Bank Employees and the Bank and (ii) all Bank Benefit Plans. Notwithstanding the foregoing, nothing herein shall limit the right of the Bank or any of its Subsidiaries to terminate any particular Bank Benefit Plan or Bank Employment Agreement in accordance with its terms.

(b) The Bank is responsible for advising Bank Employees of the details of any terms of employment with the Bank, and answering any questions relating thereto, but Seller will be allowed to review and approve, prior to its distribution, any communication

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with Bank Employees after the Closing Date that describes or refers to any of Seller’s benefits or policies, which review by Seller shall be prompt and approval by Seller shall not be unreasonably withheld.

(c) Seller shall fully vest the accounts or the accrued benefits, as the case may be, of Bank Employees in Seller’s qualified retirement plans in which the Bank Employees participate or have participated (including, without limitation, under the Boston Private Financial Holdings, Inc. 401(k) Profit Sharing Plan).

(d) Upon the Closing, any restricted stock award granted under the Boston Private Financial Holdings, Inc. 2004 Stock Option and Incentive Plan and the Boston Private Financial Holding, Inc. 2009 Stock Option and Incentive Plan (together, the “ Plans ”) to a Bank Employee which remains subject to a risk of forfeiture shall automatically vest in full and be free of any restrictions on the Closing Date. Upon the Closing, any option to acquire shares of common stock of Seller granted under the Plans to a Bank Employee (“ Seller Options ”) that is not exercisable on the Closing Date shall be immediately forfeited. Any Seller Options that are vested on the Closing Date shall remain exercisable for thirty (30) days following the Closing Date or for such longer period as shall be applicable pursuant to the terms of the Plan or an individual award agreement.

(e) Without limiting the generality of Section 6.11, nothing in this Section 5.2, express or implied, is intended to or shall confer upon any other person, including without limitation any employee or former employee, any right, benefit or remedy of any nature whatsoever under or by reason of this Agreement and no provision of this Section 5.2 shall constitute an amendment of any Bank Benefit Plan or Bank Employment Agreement. Nothing in this Agreement will be interpreted or construed to confer upon the employees any right with respect to continued employment by Seller, Buyer or their respective Affiliates, nor will this Agreement interfere in any way with the right of Seller, Buyer or their respective Affiliates to terminate any employee’s employment at any time.

5.3 Valuation .

(a) After the Closing, the Bank shall engage, at Seller’s discretion, PricewaterhouseCoopers LLP or Deloitte & Touche LLP (the “ Auditor ”) to perform a valuation (the “ Valuation ”) of the Bank’s loans for income tax purposes, and Seller shall be permitted to rely upon the Valuation for income tax purposes. Seller shall be copied on all correspondence between the Bank and Auditor, including loan data from the Bank and draft reports from Auditor. The Bank and Seller shall cooperate with respect to determining material assumptions used in the Valuation. Each of Seller and the Bank shall be responsible for one-half of the costs and expenses related to the Valuation.

(b) If Seller disagrees with any items in the Valuation, Seller shall deliver a notice describing in reasonable detail such disagreements (the “ Disputed Matters ”) and Seller and the Bank shall cooperate and use commercially reasonable efforts to resolve the Disputed Matters. If Seller and the Bank are unable to reach a mutually satisfactory resolution of the Disputed Matters within five (5) days after Seller delivers such notice to

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the Bank, Seller and the Bank shall promptly submit any remaining Disputed Matters to an independent national or regional accounting firm mutually acceptable to Seller and the Bank, that has not at any time in the five (5) years preceding the date of this Agreement provided any services for either Seller or the Bank or their respective Affiliates (the “ Independent Auditor ”), and whose sole responsibility shall be resolving the Disputed Matters. All determinations of the Independent Auditor shall be, in the absence of fraud or manifest error, final, conclusive, non-appealable and binding upon Seller and the Bank. Each of Seller and the Bank shall be responsible for half of the costs and expenses of the Independent Auditor.

5.4 Cooperation . In case at any time after the Closing Date any further action is necessary or desirable to carry out the purposes of this Agreement or to vest the Buyers with full title to the Shares, the proper officers and directors of Seller shall take all such necessary action as may be reasonably requested by the Buyers. Following the Closing, Seller and the Bank agree to cooperate in good faith to provide (or cause to be provided) to each other information that is reasonably necessary in connection with regulatory, legal, accounting, personnel, benefits and similar matters (and not relating to any dispute, litigation or arbitration between the parties hereto or their Affiliates). Each of Seller and the Bank agree that any information provided pursuant to the prior sentence of this provision shall be kept confidential and shall not be used for any purpose except for the reason given in the request. In furtherance and not in limitation of the foregoing, until the earlier of (i) the sixth (6th) anniversary of the date hereof and (ii) such time as Seller or any of its Affiliates shall dispose of such books and records in accordance with the procedures set forth in this Section 5.4, the Bank and its representatives shall have reasonable access to all of the books and records related to the Business that Seller or any of its Affiliates may retain after the Closing (the “ Retained Records ”). Such access shall be afforded by Seller and its Affiliates upon receipt of reasonable advance notice and during normal business hours. Neither Seller nor any of its Affiliates shall dispose of the Retained Records for a period of six (6) years after the date hereof. If Seller or any of its Affiliates shall desire to dispose of any Retained Records at any time after such six-year period, Seller shall, prior to such disposition, give the Bank and its representatives a reasonable opportunity to segregate and remove such Retained Records as the Bank and its representatives may select.

5.5 Tax Matters .

(a) Tax Indemnification .

(i) Seller shall pay or cause to be paid, shall be liable for, and shall indemnify, defend and hold each of the Buyers, the Bank and its Subsidiaries harmless from and against, in each case, without duplication, (A) any Taxes (and any Damages) arising from or in connection with any breach of any representation or warranty contained in Section 3.4 (determined without giving effect to any “Material Adverse Effect” or materiality qualifications contained in such representation or warranty) or covenant made in this Section 5.5 by Seller, (B) any Taxes of Seller or any of its Subsidiaries (other than the Bank and its Subsidiaries) for which the Bank or any of its Subsidiaries may be liable as a result of Treasury Regulation Section 1.1502-6 (or any similar provision of applicable law), as a transferee or successor, by contract or otherwise, and (C) any

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Taxes of the Bank and its Subsidiaries reportable on a federal consolidated Tax Return of the Seller other than for the 2008 taxable year and the short 2009 taxable year ending on the Closing Date.

(ii) The Bank shall pay or cause to be paid, shall be liable for, and shall indemnify, defend and hold Seller and its Affiliates harmless from and against (x) any and all Taxes of the Bank and its Subsidiaries arising in a Post-Closing Tax Period and (y) any and all Damages incurred by Seller or any of its Affiliates to the extent arising out of or resulting from the breach of an agreement or covenant made in this Section 5.5 by the Bank.

(iii) Payment in full of any amount due from Seller or the Bank under this Section 5.5(a) shall be made to the affected party in immediately available funds at least two business days before the date payment of the Taxes to which such payment relates is due, or, if no Tax is payable, within fifteen days after written demand is made for such payment.

(b) Preparation and Filing of Tax Returns .

(i) Seller shall timely prepare and file or shall cause to be timely prepared and filed (i) any combined, consolidated or unitary Tax Return that includes Seller or any of its Affiliates, and (ii) any Tax Return of the Bank or any of its Subsidiaries for any taxable period that ends on or before the Closing Date.

(ii) The Bank shall, except to the extent that such Tax Returns are the responsibility of Seller under Section 5.5(b)(i), timely prepare and file or shall cause to be timely prepared and filed all Tax Returns with respect to the Bank or any of its Subsidiaries.

(c) Tax Contests .

(i) If any Taxing Authority asserts a Tax Claim, then the party hereto first receiving notice of such Tax Claim promptly shall provide written notice thereof to the other party or parties hereto; provided , however , that the failure of such party to give such prompt notice shall not relieve the other party of any of its obligations under this Section 5.5, except to the extent that the other party is actually prejudiced thereby. Such notice shall specify in reasonable detail the basis for such Tax Claim and shall include a copy of the relevant portion of any correspondence received from the Taxing Authority.

(ii) Seller shall have the right to control, at its own expense, any audit, examination, contest, litigation or other proceeding by or against any Taxing Authority (a “ Tax Proceeding ”) in respect of the Bank and its Subsidiaries for any taxable period that ends on or before the Closing Date; provided, however, that, if and to the extent the Tax Proceeding relates to the Taxes of the Bank or any of its Subsidiaries and could have an adverse effect that is material on the Bank and its Affiliates, (A) Seller shall provide the Bank with a timely and reasonably detailed account of each stage of such Tax Proceeding, (B) Seller shall consult with the

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Bank and offer the Bank an opportunity to comment before submitting any written materials prepared or furnished in connection with such Tax Proceeding, (C) Seller shall defend such Tax Proceeding diligently and in good faith as if it were the only party in interest in connection with such Tax Proceeding, (D) the Bank shall be entitled to participate, at its own expense, in such Tax Proceeding and receive copies of any written materials relating to such Tax Proceeding received from the relevant Taxing Authority to the extent such Tax Proceeding relates to the 2008 taxable year and the short 2009 taxable year ending on the Closing Date, and (E) Seller shall not settle, compromise or abandon any such Tax Proceeding without obtaining the prior written consent of the Bank, which consent shall not be unreasonably withheld, conditioned or delayed.

(iii) The Bank shall have the right to control, at its own expense, any Tax Proceeding involving the Bank and its Subsidiaries (other than any Tax Proceeding described in Section 5.5(c)(ii)).

(d) Tax Payments . The Bank and its Subsidiaries shall compute their income Taxes for the 2008 taxable year and the short 2009 taxable year ending on the Closing Date as though the Bank and its Subsidiaries filed separate returns from Seller for such taxable years. To the extent such calculations result in a positive cumulative income Tax liability for either such taxable year, the Bank shall pay to Seller the full amount of such Tax liability 15 days before the applicable Tax payment is due to be made by Seller to a Taxing Authority. To the extent that the separate return taxable income of the Bank and its Subsidiaries for any such taxable year is negative and generates a income Tax Benefit to Seller and Seller’s other Subsidiaries either as a result of being able to offset such loss against taxable income of Seller and its other Subsidiaries or as a result of being able to carry back such loss against prior years’ taxable income, Seller shall pay to the Bank the amount of such Tax Benefit when and if realized by Seller or, if sooner, within 15 days after the applicable Tax Return would be due if and to the extent the Bank and its Subsidiaries would be entitled to a refund of income Tax if they had filed a separate income Tax Return historically; provided , however , that in the case of the short 2009 taxable year any gain recognized for federal income tax purposes by Seller on the sale of the Shares hereunder shall first be taken into account to offset on a dollar-for-dollar basis any negative taxable income of the Bank and its Subsidiaries, and only the net amount, if any, remaining after such offset shall be taken into account for purposes of calculating any loss or Tax Benefit for the short 2009 taxable year under this Section 5.5(d). To the extent Seller cannot currently use all of its available losses, for purposes of the preceding sentence, Seller will use a pro-rata portion of each category of losses, including the losses from the Bank and its Subsidiaries, with the remainder being carried back and then forward, as may be applicable. In the event of any adjustment to the Tax Return for the 2008 taxable year or the short 2009 taxable year ending on the Closing Date of Seller and its Subsidiaries as filed (by reason of amended return, claim for refund, or an audit), the liability of the parties under this paragraph (d) shall be re-determined to give effect to any such adjustment (including any interest owed thereon) as if it had been made as part of the original computation of Tax liability and payments between the parties shall be made at the approximate time such payments are made or refunds are received. “ Tax Benefit ” means, for any Tax year, the positive difference, if any, between (i) Taxes that would have been payable by the relevant party for such year without taking into account any such adjustment and (ii) Taxes actually payable by the party for such year.

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(e) Transfer Taxes . Notwithstanding anything to the contrary in this Agreement, Seller and the Bank shall each pay, and be responsible for, 50% of any sales Tax, use Tax, transfer Tax, documentary stamp Tax, value added Tax or similar Taxes and related fees (“ Transfer Taxes ”) imposed on the sale or transfer of the Shares pursuant to this Agreement or the entering into of this Agreement. Seller and the Bank shall cooperate in preparing and filing all Tax Returns with respect to such Transfer Taxes.

(f) Tax Refunds . Subject to Section 5.5(d), Seller shall be entitled to any refunds or credits of or against or arising from any Taxes of the Bank or any of its Subsidiaries for any taxable period that ends on or before the Closing Date or (without duplication) any Taxes paid by or on behalf of the Bank or any of its Subsidiaries on or before the Closing Date. The Bank shall be entitled to all other refunds and credits of or against or arising from any Taxes of the Bank or any of its Subsidiaries. The Bank shall forward to Seller or reimburse Seller for any refunds or credits due Seller pursuant to the terms of this Section 5.5(f) promptly after receipt thereof, and Seller shall promptly forward to the Bank or reimburse the Bank for any refunds or credits due the Bank (pursuant to the terms of this Section 5.5(f)) after receipt thereof. Each party agrees to reimburse the other party for any payments received under this Section 5.5(f) that are subsequently disallowed by any Taxing Authority.

(g) Cooperation . Not more than sixty (60) days after the receipt of a reasonable written request from Seller for a customary package of Tax information materials, the Bank shall, and shall cause its Affiliates to, provide to Seller a package of Tax information materials, including schedules and work papers, reasonably required by Seller to enable Seller to prepare and file all Tax Returns required to be prepared and filed by it with respect to the Bank. The Bank shall prepare such package completely and accurately, in good faith and in a manner consistent with Seller’s past practice. Each party to this Agreement shall, and shall cause its Affiliates to, provide to the other party to this Agreement such cooperation, documentation and information as either of them reasonably may request in (i) filing any Tax Return, amended Tax Return or claim for refund, (ii) determining a liability for Taxes or a right to refund of Taxes (including pursuant to Section 5.5(d) of this Agreement), or (iii) conducting any Tax Proceeding. Such cooperation and information shall include providing reasonably requested powers of attorney, copies of all relevant portions of relevant Tax Returns, together with all relevant portions of relevant accompanying schedules and relevant work papers, relevant documents relating to rulings or other determinations by taxing authorities and relevant records concerning the ownership and Tax basis of property and other information, which any such party may possess. Each party shall retain all Tax Returns, schedules and work papers, and all material records and other documents relating to Tax matters, of the relevant entities for their respective Tax periods ending on or pr