As filed with the Securities and Exchange Commission on July 14, 2023

Registration No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-3

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

BROOKLINE BANCORP INC.
(Exact Name of Registrant as Specified in Its Charter)

Delaware

(State or Other Jurisdiction of
Incorporation or Organization)

04-3402944

(I.R.S. Employer
Identification Number)

131 Clarendon Street
Boston, MA 02116
(617) 425-4600
(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Paul A. Perrault,
Chairman and Chief Executive Officer
131 Clarendon Street
Boston, MA 02116
(617) 425-4600

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service)

	Copies to:
	Samantha Kirby, Esq. Goodwin Procter LLP 100 Northern Avenue Boston, Massachusetts 02210 (617) 570-1000			Marissa Martin, Esq. Brookline Bancorp Inc. 131 Clarendon Street Boston, MA 02116 (617) 425-4600

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

	Large Accelerated Filer ☒			Accelerated Filer ☐
	Non-Accelerated Filer ☐			Smaller Reporting Company ☐
				Emerging Growth Company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act. ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

Neither the Securities and Exchange Commission nor any state securities commission or regulatory authority has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

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The information in this prospectus is not complete and may be changed or supplemented. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

Subject to Completion, dated July 14, 2023

PROSPECTUS

$200,000,000

Brookline Bancorp Inc.

Common Stock
Preferred Stock
Senior Debt Securities
Subordinated Debt Securities
Depositary Shares
Warrants
Units

We may offer and sell from time to time, separately or together, in multiple series or in one or more offerings, any combination of common stock, preferred stock, debt securities, warrants, depositary shares and units, up to a maximum aggregate offering price of $200,000,000.

We may offer to sell these securities on a continuous or delayed basis, through agents, dealers or underwriters, or directly to purchasers. The prospectus supplement for each offering of securities will describe in detail the plan of distribution for that offering. If our agents or any dealers or underwriters are involved in the sale of the securities, the applicable prospectus supplement will set forth the names of the agents, dealers or underwriters and any applicable commissions or discounts. Our net proceeds from the sale of securities will also be set forth in the applicable prospectus supplement. For general information about the distribution of securities offered, please see “Plan of Distribution” in this prospectus.

This prospectus provides you with a general description of the securities that we may offer and sell from time to time. Each time we sell securities we will provide a prospectus supplement that will contain specific information about the terms of the securities and sale and may add to or update the information in this prospectus. You should read this prospectus and any prospectus supplement carefully before you invest in our securities.

Our common stock is traded on the Nasdaq Global Select Market (“Nasdaq”) under the trading symbol “BRKL.” The last reported sale price of the common stock on July 12, 2023 was $9.18 per share. We have not yet determined whether any of the other securities that may be offered by this prospectus will be listed on any exchange, or included in any inter-dealer quotation or over-the-counter market. If we decide to seek the listing or inclusion of any such securities upon issuance, the prospectus supplement relating to those securities will disclose the exchange, quotation system or market on or in which the securities will be listed or included.

Investing in our securities involves risks. You should consider the risk factors described in any accompanying supplement and in any documents incorporated by reference in this prospectus. See “Risk Factors” on page 4.

The offered securities are not deposits or obligations of a bank or savings association and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

This prospectus may not be used to sell securities unless accompanied by the applicable prospectus supplement.

The date of this prospectus is , 2023.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained in this prospectus, in any related prospectus and in information incorporated by reference into this prospectus and any related prospectus that are not historical facts may constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and are intended to be covered by the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements involve risks and uncertainties. These statements, which are based on certain assumptions and describe our future plans, strategies and expectations, can generally be identified by the use of the words “may,” “will,” “should,” “could,” “would,” “plan,” “potential,” “estimate,” “project,” “believe,” “intend,” “anticipate,” “expect,” “target” and similar expressions. These forward-looking statements include, among others, statements regarding our intent, belief or expectations with respect to economic conditions, trends affecting our financial condition or results of operations, and our exposure to market, liquidity, interest-rate and credit risk. You should not place undue reliance on our forward-looking statements. You should exercise caution in interpreting and relying on forward-looking statements because they are subject to significant risks, uncertainties and other factors which are, in some cases, beyond our control.

Forward-looking statements are based on the current assumptions underlying the statements and other information with respect to the beliefs, plans, objectives, goals, expectations, anticipations, estimates and intentions of management and the financial condition, results of operations, future performance and business are only expectations of future results. Although we believe that the expectations reflected in our forward-looking statements are reasonable, our actual results could differ materially from those projected in the forward-looking statements as a result of, among other important factors, our ability to achieve the synergies and value creation contemplated in connection with the recently completed acquisition of PCSB Financial Corporation (“PCSB”); turbulence in the capital and debt markets; changes in interest rates; competitive pressures from other financial institutions; general economic conditions (including inflation and concerns about liquidity) on a national basis or in the local markets in which we operate; changes in consumer behavior due to changing political, business and economic conditions, or legislative or regulatory initiatives; changes in the value of securities and other assets in our investment portfolio; increases in loan and lease default and charge-off rates; the adequacy of allowances for loan and lease losses; decreases in deposit levels that necessitate increases in borrowing to fund loans and investments; operational risks including, but not limited to, cybersecurity incidents, fraud, natural disasters, and future pandemics; changes in regulation; the possibility that future credit losses may be higher than currently expected due to changes in economic assumptions and adverse economic developments; the risk that goodwill and intangibles recorded in our financial statements will become impaired; and changes in assumptions used in making such forward-looking statements; and the other risks and uncertainties detailed in our Annual Report on Form 10-K and updated in our Quarterly Reports on Form 10-Q and other filings submitted to the Securities and Exchange Commission (the “SEC”). Forward-looking statements speak only as of the date on which they are made. We do not undertake any obligation to update any forward-looking statement to reflect circumstances or events that occur after the date the forward-looking statements are made.

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PROSPECTUS SUMMARY

About This Prospectus

This prospectus is part of a “shelf” registration statement that we have filed under the Securities Act of 1933, as amended (the “Securities Act”), with the SEC. Under this shelf registration statement, we may sell, from time to time, any combination of the securities described in this prospectus in one or more offerings. This prospectus provides you with a general description of the securities that we may offer.

Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that specific offering and include a discussion of any risk factors or other special considerations that apply to those securities. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with the additional information described under the heading “Where You Can Find More Information.”

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

As used in this prospectus, the terms “Brookline,” the “Company,” “we,” “our,” and “us” refer to Brookline Bancorp Inc. and our consolidated subsidiaries, unless the context indicates otherwise. This prospectus includes our trademarks and other trade names identified herein. All other trademarks and trade names appearing in this prospectus are the property of their respective holders.

You should rely only on the information contained in this prospectus and the accompanying prospectus supplement or incorporated by reference in these documents. No dealer, salesperson or other person is authorized to give any information or to represent anything not contained or incorporated by reference in this prospectus or the accompanying prospectus supplement. If anyone provides you with different, inconsistent or unauthorized information or representations, you must not rely on them. This prospectus and the accompanying prospectus supplement are an offer to sell only the securities offered by these documents, but only under circumstances and in jurisdictions where it is lawful to do so. The information contained in this prospectus or any prospectus supplement is current only as of the date on the front of those documents.

About Brookline Bancorp Inc.

Brookline Bancorp, Inc., a Delaware corporation, operates as a multi-bank holding company for Brookline Bank and its subsidiaries, Bank Rhode Island (“BankRI”) and its subsidiaries, PCSB Bank and its subsidiaries, Brookline Securities Corp. and Clarendon Private, LLC (“Clarendon Private”).

Brookline Bank, headquartered in Boston, Massachusetts, has three wholly-owned subsidiaries, Longwood Securities Corp., First Ipswich Insurance Agency, and Eastern Funding LLC, and operates 29 full-service banking offices and two lending offices in the greater Boston metropolitan area. In 2020, First Ipswich Bank, formerly a wholly-owned subsidiary of the Company, was merged with and into Brookline Bank.

BankRI, headquartered in Providence, Rhode Island, has three direct subsidiaries, Acorn Insurance Agency, BRI Realty Corp., and BRI Investment Corp. and its wholly-owned subsidiary, BRI MSC Corp., and operates 20 full-service banking offices in the greater Providence, Rhode Island area. Macrolease Corporation, previously a subsidiary of BankRI, was merged into Eastern Funding LLC in the second quarter of 2022.

On January 1, 2023, the Company completed its acquisition of PCSB, the parent company of PCSB Bank. PCSB Bank, headquartered in Brewster, New York, operates as a separate subsidiary of the Company. PCSB Bank has one wholly-owned subsidiary, UpCounty Realty Corp., and operates 14 banking offices throughout the lower Hudson Valley of New York.

The Company, through Brookline Bank, BankRI and PCSB Bank (collectively, the “Banks”), offers a wide range of commercial, business and retail banking services, including a full complement of cash

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management products, on-line banking services, consumer and residential loans and investment services, designed to meet the financial needs of small- to mid-sized businesses and individuals throughout central New England and the lower Hudson Valley in New York. Specialty lending activities, including equipment financing, are focused in the New York and New Jersey metropolitan area, with services offered throughout the United States. As full-service financial institutions, the Banks and their subsidiaries focus on the continued addition of well-qualified customers, the deepening of long-term banking relationships through a full complement of products and excellent customer service, and strong risk management. Clarendon Private is a registered investment advisor with the SEC. Through Clarendon Private, the Company offers a wide range of wealth management services to individuals, families, endowments and foundations to help these clients meet their long-term financial goals.

The Company’s headquarters and executive management are located at 131 Clarendon Street, Boston, Massachusetts 02116, and its telephone number is 617-425-4600. You can find additional information regarding Brookline in its filings with the SEC referenced in the section of this document titled “Where You Can Find More Information”.

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RISK FACTORS

You should carefully consider the risks described in the documents incorporated by reference in this prospectus, before making an investment decision. These risks are not the only ones facing our company. Additional risks not presently known to us or that we currently deem immaterial may also impair our business operations. Our business, financial condition or results of operations could be materially adversely affected by the materialization of any of these risks. The trading price of our securities could decline due to the materialization of any of these risks, and you may lose all or part of your investment. This prospectus and the documents incorporated herein by reference also contain forward-looking statements that involve risks and uncertainties. Actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks described in the documents incorporated herein by reference, including (i) our Annual Reports on Form 10-K, (ii) our Quarterly Reports on Form 10-Q and (iii) documents we file with the SEC after the date of this prospectus and which are deemed incorporated by reference in this prospectus.

USE OF PROCEEDS

Unless we otherwise specify in a supplement to this prospectus, we intend to use the net proceeds from our sale of the securities covered by this prospectus for general corporate purposes, which may include: refinancing, reducing or repaying debt; investments in the Banks and our other subsidiaries as regulatory capital; financing possible investments or acquisition; expansion of the business; and investments at the holding company level.

The prospectus supplement with respect to an offering of offered securities may identify different or additional uses for the proceeds of that offering.

Except as otherwise stated in an applicable prospectus supplement, pending the application of the net proceeds, we expect to invest the proceeds in short-term obligations.

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THE SECURITIES WE MAY OFFER

This prospectus contains a summary of the common stock, the preferred stock, the senior debt securities, the subordinated debt securities, the depositary shares, the warrants and the units that we may offer. The particular material terms of the securities offered by a prospectus supplement will be described in that prospectus supplement. If indicated in the applicable prospectus supplement, the terms of the offered securities may differ from the terms summarized below. The prospectus supplement will also contain information, where applicable, about material United States federal income tax considerations relating to the offered securities, and the securities exchange, if any, on which the offered securities will be listed. The descriptions herein and in the applicable prospectus supplement do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the actual documents whose terms are summarized herein and in the applicable prospectus supplement, because those documents, and not the summaries, define your rights as holders of the relevant securities. For more information, please review the forms of these documents, which are or will be filed with the SEC and will be available as described under the heading “Where You Can Find More Information” below.

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DESCRIPTION OF DEBT SECURITIES

We may offer debt securities which may be senior or subordinated. We refer to senior debt securities and subordinated debt securities collectively as debt securities. Each series of debt securities may have different terms. The following description summarizes the general terms and provisions of the debt securities. We will describe the specific terms of the debt securities and the extent, if any, to which the general provisions summarized below apply to any series of debt securities in the prospectus supplement relating to the series and any applicable free writing prospectus that we authorize to be delivered.

We may issue senior debt securities from time to time, in one or more series under a senior indenture to be entered into between us and a senior trustee to be named in a prospectus supplement, which we refer to as the “senior trustee.” We may issue subordinated debt securities from time to time, in one or more series under a subordinated indenture to be entered into between us and a subordinated trustee to be named in a prospectus supplement, which we refer to as the “subordinated trustee.” The forms of senior indenture and subordinated indenture are filed as exhibits to the registration statement of which this prospectus forms a part. Together, the senior indenture and the subordinated indenture are referred to as the “indentures” and, together, the senior trustee and the subordinated trustee are referred to as the “trustees.” This prospectus briefly outlines some of the provisions of the indentures. The following summary of the material provisions of the indentures is qualified in its entirety by the provisions of the indentures, including definitions of certain terms used in the indentures. Wherever we refer to particular sections or defined terms of the indentures, those sections or defined terms are incorporated by reference in this prospectus or the applicable prospectus supplement. You should review the indentures that are filed as exhibits to the registration statement, of which this prospectus forms a part, for additional information. As used in this prospectus, the term “debt securities” includes the debt securities being offered by this prospectus and all other debt securities issued by us under the indentures.

General

The indentures:

•

do not limit the amount of debt securities that we may issue;

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allow us to issue debt securities in one or more series;

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do not require us to issue all of the debt securities of a series at the same time; and

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allow us to reopen a series to issue additional debt securities without the consent of the holders of the debt securities of such series.

Unless otherwise provided in the applicable prospectus supplement, the senior debt securities will be unsubordinated obligations and will rank equally with all of our other unsecured and unsubordinated indebtedness. Payments on the subordinated debt securities will be subordinated to the prior payment in full of all of our senior indebtedness, as described under “— Subordination” and in the applicable prospectus supplement.

Each indenture provides that we may, but need not, designate more than one trustee under an indenture. Any trustee under an indenture may resign or be removed and a successor trustee may be appointed to act with respect to the series of debt securities administered by the resigning or removed trustee. If two or more persons are acting as trustee with respect to different series of debt securities, each trustee shall be a trustee of a trust under the applicable indenture separate and apart from the trust administered by any other trustee. Except as otherwise indicated in this prospectus, any action described in this prospectus to be taken by each trustee may be taken by each trustee with respect to, and only with respect to, the one or more series of debt securities for which it is trustee under the applicable indenture.

The prospectus supplement for each offering will provide the following terms, where applicable:

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the title of the debt securities and whether they are senior or subordinated;

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the aggregate principal amount of the debt securities being offered, the aggregate principal amount of the debt securities outstanding as of the most recent practicable date and any limit on their aggregate principal amount, including the aggregate principal amount of debt securities authorized;

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the price at which the debt securities will be issued, expressed as a percentage of the principal and, if other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof or, if applicable, the portion of the principal amount of such debt securities that is convertible into common stock or other securities of ours or the method by which any such portion shall be determined;

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if convertible, the terms on which such debt securities are convertible, including the initial conversion price or rate and the conversion period and any applicable limitations on the ownership or transferability of common stock or other securities of ours received on conversion;

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the date or dates, or the method for determining the date or dates, on which the principal of the debt securities will be payable;

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the fixed or variable interest rate or rates of the debt securities, or the method by which the interest rate or rates is determined;

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the date or dates, or the method for determining the date or dates, from which interest will accrue;

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the dates on which interest will be payable;

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the record dates for interest payment dates, or the method by which such dates will be determined;

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the persons to whom interest will be payable;

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the place or places where the principal of, and any premium or make-whole amount, and interest on, the debt securities will be payable;

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the place or places where the principal of, and any premium or make-whole amount, and interest on, the debt securities will be payable;

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where the debt securities may be surrendered for registration of transfer or conversion or exchange;

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where notices or demands to or upon us in respect of the debt securities and the applicable indenture may be served;

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the times, prices and other terms and conditions upon which we may redeem the debt securities;

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any obligation we have to redeem, repay or purchase the debt securities pursuant to any sinking fund or analogous provision or at the option of holders of the debt securities, and the times and prices at which we must redeem, repay or purchase the debt securities as a result of such obligation;

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the currency or currencies in which the debt securities are denominated and payable if other than United States dollars, which may be a foreign currency or units of two or more foreign currencies or a composite currency or currencies and the terms and conditions relating thereto, and the manner of determining the equivalent of such foreign currency in United States dollars;

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whether the principal of, and any premium or make-whole amount, or interest on, the debt securities of the series are to be payable, at our election or at the election of a holder, in a currency or currencies other than that in which the debt securities are denominated or stated to be payable, and other related terms and conditions;

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whether the debt securities will be in registered form, bearer form, or both, and (i) if in registered form, the person to whom any interest shall be payable, if other than the person in whose name the security is registered at the close of business on the regular record date for such interest, or (ii) if in bearer form, the manner in which, or the person to whom, any interest on the security shall be payable if otherwise than upon presentation and surrender upon maturity;

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any restrictions applicable to the offer, sale or delivery of securities in bearer form and the terms upon which securities in bearer form of the series may be exchanged for securities in registered form of the series and vice versa, if permitted by applicable laws and regulations;

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whether any debt securities of the series are to be issuable initially in temporary global form and whether any debt securities of the series are to be issuable in permanent global form with or without coupons and, if so, whether beneficial owners of interests in any such permanent global security may, or shall be required to, exchange their interests for other debt securities of the series, and the manner in which interest shall be paid;

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the identity of the depositary for securities in registered form, if such series are to be issuable as a global security;

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the applicability, if any, of the defeasance and covenant defeasance provisions described in this prospectus or in the applicable indenture;

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whether and under what circumstances we will pay any additional amounts on the debt securities in respect of any tax, assessment or governmental charge;

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whether and under what circumstances the debt securities being offered are convertible into common stock or other securities of ours, as the case may be, including the conversion price or rate and the manner or calculation thereof;

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the name of the applicable trustee and the nature of any material relationship with us or any of our affiliates, and the percentage of debt securities of the class necessary to require the trustee to take action; and

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any other terms of such debt securities not inconsistent with the provisions of the applicable indenture.

We may issue debt securities that provide for less than the entire principal amount thereof to be payable upon declaration of acceleration of the maturity of the debt securities. We refer to any such debt securities throughout this prospectus as “original issue discount securities.” The applicable prospectus supplement will describe the United States federal income tax consequences and other relevant considerations applicable to original issue discount securities.

Except as described under “— Merger, Consolidation or Sale of Assets” or as may be set forth in any prospectus supplement, the debt securities will not contain any provisions that (i) would limit our ability to incur indebtedness or (ii) would afford holders of debt securities protection in the event of (a) a highly leveraged or similar transaction involving us, or (b) a change of control or reorganization, restructuring, merger or similar transaction involving us that may adversely affect the holders of the debt securities. In the future, we may enter into transactions, such as the sale of all or substantially all of our assets or a merger or consolidation, that may have an adverse effect on our ability to service our indebtedness, including the debt securities, by, among other things, substantially reducing or eliminating our assets.

Neither the governing law nor our governing instruments define the term “substantially all” as it relates to the sale of assets. Consequently, to determine whether a sale of “substantially all” of our assets has occurred, a holder of debt securities must review the financial and other information that we have disclosed to the public.

We will provide you with more information in the applicable prospectus supplement regarding any deletions, modifications, or additions to the events of default or covenants that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

Payment

Unless otherwise provided in the applicable prospectus supplement, the principal of, and any premium or make-whole amount, and interest on, any series of the debt securities will be payable by mailing a check to the address of the person entitled to it as it appears in the applicable register for the debt securities or by wire transfer of funds to that person at an account maintained within the United States.

All monies that we pay to a paying agent or a trustee for the payment of the principal of, and any premium or make-whole amount, or interest on, any debt security will be repaid to us if unclaimed at the end of two years after the obligation underlying payment becomes due and payable. After funds have been returned to us, the holder of the debt security may look only to us for payment, without payment of interest for the period which we hold the funds.

Denomination, Interest, Registration and Transfer

Unless otherwise described in the applicable prospectus supplement, the debt securities of any series will be issuable in denominations of $1,000 and integral multiples of $1,000.

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Interest on the debt securities shall be computed on the basis of a 360-day year composed of twelve 30-day months.

Subject to the limitations imposed upon debt securities that are evidenced by a computerized entry in the records of a depository company rather than by physical delivery of a note, a holder of debt securities of any series may:

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exchange them for any authorized denomination of other debt securities of the same series and of a like aggregate principal amount and kind upon surrender of such debt securities at the corporate trust office of the applicable trustee or at the office of any transfer agent that we designate for such purpose; and

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surrender them for registration of transfer or exchange at the corporate trust office of the applicable trustee or at the office of any transfer agent that we designate for such purpose.

Every debt security surrendered for registration of transfer or exchange must be accompanied by a written instrument of transfer satisfactory to the applicable trustee or transfer agent. Payment of a service charge will not be required for any registration of transfer or exchange of any debt securities, but we or the trustee may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. We may at any time designate additional transfer agents for any series of debt securities.

Neither we, nor any trustee, will be required to:

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issue, register the transfer of, or exchange debt securities of any series during a period beginning at the opening of business 15 days before the day that the notice of redemption of any debt securities selected for redemption is mailed and ending at the close of business on the day of such mailing;

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register the transfer of, or exchange any debt security, or portion thereof, so selected for redemption, in whole or in part, except the unredeemed portion of any debt security being redeemed in part; and

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issue, register the transfer of, or exchange any debt security that has been surrendered for repayment at the option of the holder, except the portion, if any, of such debt security not to be so repaid.

Merger, Consolidation or Sale of Assets

The indentures provide that we may, without the consent of the holders of any outstanding debt securities, (i) consolidate with, (ii) sell, lease or convey all or substantially all of our assets to, or (iii) merge with or into, any other entity provided that:

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either we are the continuing entity, or the successor entity, if other than us, assumes the obligations (a) to pay the principal of, and any premium or make-whole amount, and interest on, all of the debt securities and (b) to duly perform and observe all of the covenants and conditions contained in the applicable indenture;

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after giving effect to the transaction, there is no event of default under the applicable indentures and no event which, after notice or the lapse of time, or both, would become such an event of default, occurs and continues; and

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an officers’ certificate and legal opinion covering such conditions are delivered to each applicable trustee.

Events of Default, Notice and Waiver

Unless the applicable prospectus supplement states otherwise, when we refer to “events of default” as defined in the indentures with respect to any series of debt securities, we mean:

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default in in the payment of any installment of interest on any debt security of such series continuing for 90 days unless such date has been extended or deferred;

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default in in the payment of principal of, or any premium or make-whole amount on, any debt security of such series when due and payable unless such date has been extended or deferred;

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default in the performance or breach of any covenant or warranty in the debt securities or in the indenture by us continuing for 90 days after written notice described below;

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bankruptcy, insolvency or reorganization, or court appointment of a receiver, liquidator or trustee of us; and

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any other event of default provided with respect to a particular series of debt securities.

If an event of default occurs and is continuing with respect to debt securities of any series outstanding, then the applicable trustee or the holders of 25% or more in principal amount of the debt securities of that series will have the right to declare the principal amount of all the debt securities of that series to be due and payable. If the debt securities of that series are original issue discount securities or indexed securities, then the applicable trustee or the holders of 25% or more in principal amount of the debt securities of that series will have the right to declare the portion of the principal amount as may be specified in the terms thereof to be due and payable. However, at any time after such a declaration of acceleration has been made, but before a judgment or decree for payment of the money due has been obtained by the applicable trustee, the holders of at least a majority in principal amount of outstanding debt securities of such series or of all debt securities then outstanding under the applicable indenture may rescind and annul such declaration and its consequences if:

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we have deposited with the applicable trustee all required payments of the principal, any premium or make-whole amount, interest and, to the extent permitted by law, interest on overdue installment of interest, plus applicable fees, expenses, disbursements and advances of the applicable trustee; and

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all events of default, other than the non-payment of accelerated principal, or a specified portion thereof, and any premium or make-whole amount, have been cured or waived.

The indentures require each trustee to give notice to the holders of debt securities within the later of 90 days after an event of default and 30 days after the event of default is actually known to a responsible officer of such trustee, unless such default has been cured or waived. However, the trustee may withhold notice if specified persons of such trustee consider such withholding to be in the interest of the holders of debt securities.

The indentures provide that holders of debt securities of any series may not institute any proceedings, judicial or otherwise, with respect to such indenture or for any remedy under the indenture, unless the trustee fails to act for a period of 90 days after the trustee has received a written request to institute proceedings in respect of an event of default from the holders of 25% or more in principal amount of the outstanding debt securities of such series, as well as an offer of indemnity reasonably satisfactory to the trustee. However, this provision will not prevent any holder of debt securities from instituting suit for the enforcement of payment of the principal of, and any premium or make-whole amount, and interest on, such debt securities at the respective due dates thereof.

The indentures provide that, subject to provisions in each indenture relating to its duties in the case of a default, a trustee has no obligation to exercise any of its rights or powers at the request or direction of any holders of any series of debt securities then outstanding under the indenture, unless the holders have offered to the trustee reasonable security or indemnity. The holders of at least a majority in principal amount of the outstanding debt securities of any series or of all debt securities then outstanding under an indenture shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the applicable trustee, or of exercising any trust or power conferred upon such trustee. However, a trustee may refuse to follow any direction which:

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is in conflict with any law or the applicable indenture;

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may involve the trustee in personal liability; or

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may be unduly prejudicial to the holders of debt securities of the series not joining the proceeding.

Within 120 days after the close of each fiscal year, we will be required to deliver to each trustee a certificate, signed by one of our several specified officers, stating whether or not that officer has knowledge of any default under the applicable indenture. If the officer has knowledge of any default, the notice must specify the nature and status of the default.

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Modification of the Indentures

The indentures provide that modifications and amendments may be made only with the consent of the affected holders of a majority in principal amount of all outstanding debt securities issued under that indenture.

We and our respective trustee may make modifications and amendments of an indenture without the consent of any holder of debt securities for any of the following purposes:

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to evidence the succession of another person to us as obligor under such indenture;

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to provide for uncertificated debt securities in addition to or in place of certificated debt securities;

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to add to our covenants for the benefit of the holders of all or any series of debt securities or to surrender any right or power conferred upon us in such indenture;

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to add events of default for the benefit of the holders of all or any series of debt securities;

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to add to, delete from, or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication, and delivery of debt securities;

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to make any change that does not adversely affect the rights of any securityholder in any material respect;

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to establish the form or terms of debt securities of any series;

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to provide for the acceptance of appointment by a successor trustee or facilitate the administration of the trusts under an indenture by more than one trustee; or

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to cure any ambiguity, defect or inconsistency in an indenture, provided that such action shall not adversely affect the interests of holders of debt securities of any series issued under such indenture in any material respect.

Voting

The indentures provide that in determining whether the holders of the requisite principal amount of outstanding debt securities of a series have given any request, demand, authorization, direction, notice, consent or waiver under the indentures or whether a quorum is present at a meeting of holders of debt securities, the principal amount of an original issue discount security that shall be deemed to be outstanding shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon declaration of acceleration of the maturity thereof.

Subordination

Unless otherwise provided in the applicable prospectus supplement, subordinated debt securities will be subject to the following subordination provisions.

Upon any distribution to our creditors in a liquidation, dissolution or reorganization, the payment of the principal of and interest on any subordinated debt securities will be subordinated to the extent provided in the applicable indenture in right of payment to the prior payment in full of all senior debt. However, our obligation to make payments of the principal of and interest on such subordinated debt securities otherwise will not be affected. No payment of principal or interest will be permitted to be made on subordinated debt securities at any time if a default on senior debt exists that permits the holders of such senior debt to accelerate its maturity and the default is the subject of judicial proceedings or we receive notice of the default. After all senior debt is paid in full and until the subordinated debt securities are paid in full, holders of subordinated debt securities will be subrogated to the rights of holders of senior debt to the extent that distributions otherwise payable to holders of subordinated debt securities have been applied to the payment of senior debt. The subordinated indenture will not restrict the amount of senior debt or other indebtedness of ours. As a result of these subordination provisions, in the event of a distribution of assets upon insolvency, holders of subordinated debt securities may recover less, ratably, than our general creditors.

No restrictions will be included in any indenture relating to subordinated debt securities upon the creation of additional senior debt.

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If this prospectus is being delivered in connection with the offering of a series of subordinated debt securities, the accompanying prospectus supplement or the information incorporated in this prospectus by reference will set forth the approximate amount of senior debt outstanding as of the end of our most recent fiscal quarter.

Discharge, Defeasance and Covenant Defeasance

Unless otherwise indicated in the applicable prospectus supplement, the indentures allow us to discharge our obligations to holders of any series of debt securities issued under any indenture when:

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either (i) all securities of such series have already been delivered to the applicable trustee for cancellation; or (ii) all securities of such series have not already been delivered to the applicable trustee for cancellation but (a) have become due and payable, (b) will become due and payable within one year, or (c) if redeemable at our option, are to be redeemed within one year, and we have irrevocably deposited with the applicable trustee, in trust, funds in such currency or currencies, currency unit or units or composite currency or currencies in which such debt securities are payable, an amount sufficient to pay the entire indebtedness on such debt securities in respect of principal of, and any premium or make-whole amount, and interest to the date of such deposit if such debt securities have become due and payable or, if they have not, to the stated maturity or redemption date;

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we have paid or caused to be paid all other sums payable; and

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an officers’ certificate and an opinion of counsel stating the conditions to discharging the debt securities have been satisfied has been delivered to the trustee.

Unless otherwise provided in the applicable prospectus supplement, the indentures provide that, upon our irrevocable deposit with the applicable trustee, in trust, of an amount, in such currency or currencies, currency unit or units or composite currency or currencies in which such debt securities are payable at stated maturity, or government obligations, or both, applicable to such debt securities, which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal of, and any premium or make-whole amount, and interest on, such debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates therefor, we shall be released from our obligations with respect to such debt securities under the applicable indenture or, if provided in the applicable prospectus supplement, our obligations with respect to any other covenant, and any omission to comply with such obligations shall not constitute an event of default with respect to such debt securities.

Notwithstanding the above, we may not elect to defease and be discharged from the obligation to pay any additional amounts upon the occurrence of particular events of tax, assessment or governmental charge with respect to payments on such debt securities and the obligations to register the transfer or exchange of such debt securities, to replace temporary or mutilated, destroyed, lost or stolen debt securities, to maintain an office or agency in respect of such debt securities, or to hold monies for payment in trust.

The applicable prospectus supplement may further describe the provisions, if any, permitting such defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to the debt securities of or within a particular series.

Conversion Rights

The terms and conditions, if any, upon which the debt securities are convertible into common stock or other securities of ours will be set forth in the applicable prospectus supplement. The terms will include whether the debt securities are convertible into common stock or other securities of ours, the conversion price, or manner of calculation thereof, the conversion period, provisions as to whether conversion will be at our option or the option of the holders, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of the debt securities and any restrictions on conversion.

No Recourse

There is no recourse under any obligation, covenant or agreement in the applicable indenture or with respect to any security against any of our or our successor’s past, present or future shareholders, employees, officers or directors.

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DESCRIPTION OF COMMON STOCK

The following is a description of the material terms and provisions of our common stock. It may not contain all the information that is important to you. You can access complete information by referring to our certificate of incorporation and bylaws and the Delaware General Corporation Law, or DGCL. The certificate of incorporation and bylaws are incorporated by reference into this prospectus, and the following summary is qualified in its entirety by reference to such documents.

General

Under our certificate of incorporation, we have the authority, without further shareholder action, to issue up to 200,000,000 shares of common stock, par value $0.01 per share. We may amend our certificate of incorporation from time to time to increase the number of authorized shares of common stock. Any such amendment would require the approval of the majority of the votes entitled to be cast in respect of such capital stock.

As of July 13, 2023, we had 88,955,202 shares of common stock outstanding. Our common stock is listed on Nasdaq under the symbol “BRKL.”

We may issue common stock from time to time. Our Board of Directors must approve the amount of stock we sell and the price for which it is sold. Holders of our common stock do not have any preferential rights or preemptive rights to buy or subscribe for capital stock or other securities that we may issue. Our common stock does not have any redemption or sinking fund provisions or any conversion rights.

Dividends

We may pay dividends on our common stock if, after giving effect to the distribution, we would be able to pay our indebtedness as the indebtedness comes due in the usual course of business and our total assets exceed the sum of our liabilities and the amount needed, if we were to be dissolved at the time of the distribution, to satisfy the preferential rights upon dissolution of any holders of capital stock who have preference in the event of dissolution. The holders of common stock are entitled to receive and share equally in dividends as may be declared by the our Board of Directors out of funds legally available therefor. If we issue shares of preferred stock, the holders thereof may have a priority over the holders of the common stock with respect to dividends.

Liquidation

In the event of any liquidation, dissolution or winding up of the Company, and subject to the preferential rights of any other class or series of stock, holders of shares of the common stock are entitled to receive all assets of the Company available for distribution, after payment or provision for payment of all our debts and liabilities, including deposit accounts and accrued interest thereon, and after distribution of the balance in the liquidation account to eligible account holders.

Voting Rights

Subject to the provisions of the certificate of incorporation, each holder of common stock is entitled to one vote per share and has no right to cumulate votes in the election of directors. Holders of our common stock elect our Board of Directors and act on all other matters as are required to be presented to them under Delaware law or as are otherwise presented to them by our Board of Directors.

Under our certificate of incorporation, any person who beneficially owns more than 10% of the then-outstanding shares of the our common stock will not be entitled or permitted to vote any shares of common stock held in excess of the 10% limit.

All matters to be voted on by stockholders, other than a contested election of directors, must be approved by a majority of the votes cast at a meeting of stockholders duly called and at which a quorum is present, subject to any voting rights granted to holders of any then outstanding preferred stock. In contested elections of directors, which generally will include any situation in which Brookline receives a notice that a stockholder has nominated a person for election to the Board of Directors at a meeting of the stockholders

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DESCRIPTION OF PREFERRED STOCK

This section describes the general terms and provisions of shares of Brookline’s preferred stock that we may offer by this prospectus. Brookline may issue preferred stock in one or more series; each series of preferred stock will have its own rights and preferences. We will describe in a prospectus supplement (1) the specific terms of the series of any preferred stock offered through that prospectus supplement and (2) any general terms outlined in this section that will not apply to those shares of preferred stock. This summary of terms is not complete. For additional information before you buy any preferred stock you should read the certificate of incorporation and bylaws of Brookline that are in effect on the date that we offer any preferred stock, as well as any applicable amendment to our certificate of incorporation designating the terms of a series of preferred stock.

General

Under our certificate of incorporation, we have the authority to issue up to 50,000,000 shares of preferred stock, par value $0.01 per share. Prior to issuing shares of preferred stock of a particular series, our Board of Directors will determine or fix the terms of that series of preferred stock, as described below.

When we issue shares of preferred stock, they will be fully paid and nonassessable. This means the full purchase price for the outstanding preferred stock will be paid at issuance and that the purchasers of shares of preferred stock will not be required later to pay us any additional consideration for those shares. The preferred stock will have no preemptive rights to subscribe for any additional securities which we may issue in the future. This means that the purchasers of shares of preferred stock will not receive any rights, as a holder of preferred stock, to buy any portion of the securities which we may issue in the future. Because our Board of Directors has the power to establish the preferences and rights of each class or series of preferred stock, our Board of Directors may grant the holders of any series or class of preferred stock preferences, powers, and rights, voting or otherwise, senior to the rights of holders of shares of common stock. The issuance or possibility of issuance of preferred stock could have the effect of delaying or preventing a change in control of our company.

Terms

You should refer to the prospectus supplement relating to the offering of a class or series of preferred stock or the certificate of designations designating the class or series of preferred stock for the specific terms of that class or series, including:

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the distinctive class or serial designation and the number of shares constituting such class or series;

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the dividend rates or the amount of dividends to be paid on the shares of such class or series, whether dividends shall be cumulative and, if so, from which date or dates, the payment date or dates for dividends, and the participating and other rights, if any, with respect to dividends;

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the voting powers, full or limited, if any, of the shares of such class or series;

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whether the shares of such class or series shall be redeemable and, if so, the price or prices at which, and the terms and conditions on which, such shares may be redeemed;

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the amount or amounts payable upon the shares of such class or series and any preferences applicable thereto in the event of our voluntary or involuntary liquidation, dissolution or winding up;

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whether the shares of such class or series shall be entitled to the benefit of a sinking or retirement fund to be applied to the purchase or redemption of such shares, and if so entitled, the amount of such fund and the manner of its application, including the price or prices at which such shares may be redeemed or purchased through the application of such fund;

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whether the shares of such class or series shall be convertible into, or exchangeable for, shares of any other class or classes or of any other series of the same or any other class or classes of our stock and, if so convertible or exchangeable, the conversion price or prices, or the rate or rates of exchange, and the adjustments thereof, if any, at which such conversion or exchange may be made, and any other terms and conditions of such conversion or exchange;

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DESCRIPTION OF DEPOSITARY SHARES

This section describes the general terms and provisions of the depositary shares offered by this prospectus. The applicable prospectus supplement will describe the specific terms of any issuance of depositary shares. You should read the particular terms of any depositary shares we offer in any prospectus supplement, together with the more detailed form of deposit agreement, including the form of depositary receipt relating to the depositary shares, which will be filed as an exhibit to a document incorporated by reference in the registration statement of which this prospectus forms a part. The prospectus supplement also will state whether any of the terms summarized below do not apply to the depositary shares being offered.

General

We may offer fractional, rather than full shares of preferred stock. If we exercise this option, we will provide for the issuance by a depositary to the public of depositary receipts evidencing depositary shares, each of which will represent a fractional interest (to be stated in the applicable prospectus supplement relating to a particular series of the preferred stock) in a share of a particular series of the preferred stock.

We will deposit the shares of any series of the preferred stock underlying the depositary shares under a separate deposit agreement between us and a bank or trust company selected by us, known as a depositary, having its principal office in the United States, and having a combined capital and surplus of at least $50 million. The applicable prospectus supplement will provide the name and address of the depositary. Subject to the terms of the deposit agreement, each owner of a depositary share will have a fractional interest in all the rights and preferences of the preferred stock underlying the depositary share. These rights include any dividend, voting, redemption, conversion and liquidation rights.

While the final depositary receipts are being prepared, we may order the depositary, in writing, to issue temporary depositary receipts substantially identical to the final depositary receipts although not in final form. This will entitle the holders to all the rights relating to the final depositary receipts. Final depositary receipts will be prepared without unreasonable delay, and the holders of the temporary depositary receipts can exchange them for the final depositary receipts at our expense.

Withdrawal of Preferred Stock

If you surrender depositary receipts at the principal corporate trust office of the depositary (unless the related depositary shares have previously been called for redemption), you are entitled to receive at that office, should you so request, the number of shares of preferred stock and any money or other property represented by the depositary shares. We will not issue partial shares of preferred stock. If you deliver a number of depositary receipts evidencing a number of depositary shares that represent more than a whole number of depositary shares of preferred stock to be withdrawn, the depositary will issue you a new depositary receipt evidencing the excess number of depositary shares at the same time that the preferred stock is withdrawn. Holders of preferred stock will no longer be entitled to deposit these shares under the deposit agreement or to receive depositary shares in exchange for those withdrawn shares of preferred stock. We cannot assure you that a market will exist for the withdrawn preferred stock.

Dividends and Other Distributions

The depositary will distribute all cash dividends or other cash distributions received for the preferred stock (less any taxes required to be withheld) to the record holders of depositary shares representing the preferred stock in proportion to the number of depositary shares that the holders own on the relevant record date. The depositary will distribute only the amount that can be distributed without attributing to any holder of depositary shares a fraction of one cent. The balance not distributed will be added to and treated as part of the next sum that the depositary receives for distribution to record holders of depositary shares.

If there is a distribution other than in cash, the depositary will distribute property to the record holders of depositary shares that are entitled to it, unless the depositary determines that it is not feasible to make this distribution. If this occurs, the depositary may, with our approval, sell the property and distribute the net proceeds from the sale to the holders of depositary shares.

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The deposit agreement will also contain provisions relating to the manner in which any subscription or similar rights that we offer to holders of the preferred stock will be made available to holders of depositary shares.

Conversion and Exchange

Unless the applicable prospectus supplement indicates otherwise, the series of preferred stock underlying the depositary shares will not be convertible or exchangeable into any other class or series of our capital stock.

Redemption of Deposited Preferred Stock

If a series of preferred stock underlying the depositary shares is subject to redemption, we will redeem the depositary shares from the redemption proceeds received by the depositary, in whole or in part, on the series of preferred stock held by the depositary. The redemption price per depositary share will bear the same relationship to the redemption price per share of preferred stock that the depositary share bears to the underlying preferred stock. When we redeem preferred stock held by the depositary, the depositary will redeem as of the same redemption date, the number of depositary shares representing the preferred stock redeemed. If less than all the depositary shares are to be redeemed, the redemption will be made in a manner that our Board of Directors decides is equitable.

From and after the date fixed for redemption, the depositary shares called for redemption will no longer be outstanding. When the depositary shares are no longer outstanding, all rights of the holders of depositary shares will cease, except the right to receive money or property that the holders of the depositary shares were entitled to receive on redemption. The payments will be made when holders surrender their depositary receipts to the depositary.

Voting of Deposited Preferred Stock

Upon receipt of notice of any meeting at which the holders of the preferred stock are entitled to vote, the depositary will mail the information contained in the notice to the record holders of the depositary shares relating to the preferred stock. Each record holder of the depositary shares on the record date (which will be the same date as the record date for the preferred stock) will be entitled to instruct the depositary on how the preferred stock underlying the holder’s depositary shares should be voted. The depositary will try, if practicable, to vote the number of shares of preferred stock underlying the depositary shares according to the instructions received, and we will take all action that the depositary may consider necessary to enable the depositary to do so. The depositary will not vote any preferred stock if it does not receive specific instructions from the holders of depositary shares relating to the preferred stock.

Taxation

Owners of depositary shares will be treated for United States federal income tax purposes as if they were owners of the preferred stock represented by the depositary shares. Accordingly, for United States federal income tax purposes, they will have the income and deductions to which they would have been entitled if they were holders of the preferred stock. In addition:

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no gain or loss will be recognized for federal income tax purposes when preferred stock is withdrawn in exchange for depositary shares as provided in the deposit agreement;

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the tax basis of each share of preferred stock to an exchanging owner of depositary shares will, at the exchange, be the same as the aggregate tax basis of the depositary shares exchanged; and

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the holding period for the preferred stock in the hands of an exchanging owner of depositary shares who held the depositary shares as a capital asset at the time of the exchange, will include the period during which the person owned the depositary shares.

Amendment and Termination of the Deposit Agreement

Unless otherwise provided in the applicable prospectus supplement or required by law, the form of depositary receipt evidencing the depositary shares and any provision of the deposit agreement may be

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amended at any time by an agreement between us and the depositary. A deposit agreement may be terminated by either the depositary or us only if:

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all outstanding depositary shares relating to the deposit agreement have been redeemed; or

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there has been a final distribution on the preferred stock of the relevant series in connection with our liquidation, dissolution or winding up and the distribution has been distributed to the holders of the related depositary receipts evidencing the depositary shares.

Charges of Depositary

We will pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. We will pay charges of the depositary associated with the initial deposit and any redemption of the preferred stock. Holders of depositary shares will pay transfer and other taxes and governmental charges, and any other charges that are stated to be their responsibility in the deposit agreement.

Resignation and Removal of Depositary

The depositary may resign at any time by delivering notice to us. We also may remove the depositary at any time. Resignations or removals will be effective when a successor depositary is appointed, and when the successor accepts the appointment. A successor depositary must be appointed within 60 days after delivery of the notice of resignation or removal. A successor depositary must be a bank or trust company having its principal office in the United States, and having a combined capital and surplus of at least $50 million.

Miscellaneous

The depositary will forward to the holders of depositary shares all reports and communications that it receives from us, and that we are required to furnish to the holders of the preferred stock.

Neither we nor the depositary will be liable if the depositary is prevented or delayed by law or any circumstance beyond its control in performing its obligations under the deposit agreement. Our obligations and the depositary’s obligations under the deposit agreement will be limited to performance in good faith of the duties described in the deposit agreement. Neither we nor the depositary will be obligated to prosecute or defend any legal proceeding connected with any depositary shares or preferred stock unless satisfactory indemnity is furnished to the depositary and us. We and the depositary may rely on written advice of counsel or accountants, or information provided by persons presenting preferred stock for deposit, holders of depositary shares or other persons believed to be competent and on documents believed to be genuine.

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DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement, which includes this prospectus.

General

We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities.

We will evidence each series of warrants by warrant certificates that we will issue under a separate warrant agreement. We will enter into the warrant agreement with a warrant agent. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.

We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

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the offering price and aggregate number of warrants offered;

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the currency for which the warrants may be purchased;

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if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

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if applicable, the date on and after which the warrants and the related securities will be separately transferable;

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in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

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in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;

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the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreement and the warrants;

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the terms of any rights to redeem or call the warrants;

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any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

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the periods during which, and places at which, the warrants are exercisable;

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the manner of exercise;

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the dates on which the right to exercise the warrants will commence and expire;

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the manner in which the warrant agreement and warrants may be modified;

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federal income tax consequences of holding or exercising the warrants;

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the terms of the securities issuable upon exercise of the warrants; and

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any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

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DESCRIPTION OF UNITS

We may issue units comprised of shares of common stock, shares of preferred stock, debt securities and warrants in any combination. We may issue units in such amounts and in as many distinct series as we wish. This section outlines certain provisions of the units that we may issue. If we issue units, they will be issued under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. The information described in this section may not be complete in all respects and is qualified entirely by reference to the unit agreement with respect to the units of any particular series. The specific terms of any series of units offered will be described in the applicable prospectus supplement. If so described in a particular supplement, the specific terms of any series of units may differ from the general description of terms presented below. We urge you to read any prospectus supplement related to any series of units we may offer, as well as the complete unit agreement and unit certificate that contain the terms of the units. If we issue units, forms of unit agreements and unit certificates relating to such units will be incorporated by reference as exhibits to the registration statement, which includes this prospectus.

Each unit that we may issue will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

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the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;

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any provisions of the governing unit agreement;

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the price or prices at which such units will be issued;

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the applicable U.S. federal income tax considerations relating to the units;

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any provisions for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; and

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any other terms of the units and of the securities comprising the units.

The provisions described in this section, as well as those described under “Description of Common Stock,” “Description of Preferred Stock,” “Description of Debt Securities” and “Description of Warrants” will apply to the securities included in each unit, to the extent relevant and as may be updated in any prospectus supplements.

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PLAN OF DISTRIBUTION

We may sell securities:

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through underwriters;

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through dealers;

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through agents;

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directly to purchasers; or

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through a combination of any of these methods or any other method permitted by law.

In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing security holders.

We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers. In the prospectus supplement relating to such offering, we will name any agent that could be viewed as an underwriter under the Securities Act and describe any commissions that we must pay to any such agent. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

The distribution of the securities may be effected from time to time in one or more transactions:

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at a fixed price, or prices, which may be changed from time to time;

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at market prices prevailing at the time of sale;

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at prices related to such prevailing market prices; or

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at negotiated prices.

Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.

The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:

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the name of the agent or any underwriters;

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the public offering or purchase price;

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any discounts and commissions to be allowed or paid to the agent or underwriters;

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all other items constituting underwriting compensation;

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any discounts and commissions to be allowed or paid to dealers; and

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any exchanges on which the securities will be listed.

If any underwriters or agents are used in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement, sales agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

In connection with the offering of securities, we may grant to the underwriters an option to purchase additional securities with an additional underwriting commission, as may be set forth in the accompanying prospectus supplement. If we grant any such option, the terms of such option will be set forth in the prospectus supplement for such securities.

If a dealer is used in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer, who may be deemed to be an “underwriter” as that term

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is defined in the Securities Act, may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

If we offer securities in a subscription rights offering to our existing security holders, we may enter into a standby underwriting agreement with dealers, acting as standby underwriters. We may pay the standby underwriters a commitment fee for the securities they commit to purchase on a standby basis. If we do not enter into a standby underwriting arrangement, we may retain a dealer-manager to manage a subscription rights offering for us.

Agents, underwriters, dealers and other persons may be entitled under agreements which they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, and agents may be customers of, engage in transactions with, or perform services for, us in the ordinary course of business.

If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

•

the purchase by an institution of the securities covered under that contract shall not at the time of delivery be prohibited under the laws of the jurisdiction to which that institution is subject; and

•

if the securities are also being sold to underwriters acting as principals for their own account, the underwriters shall have purchased such securities not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.

Offered securities may also be offered and sold, if so indicated in the prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more remarketing firms, acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with their remarketing of offered securities.

Certain agents, underwriters and dealers, and their associates and affiliates, may be customers of, have borrowing relationships with, engage in other transactions with, or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.

In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may over allot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions.

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If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

Under Rule 15c6-1 of the Securities Exchange Act of 1934 (the “Exchange Act”), trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise. The applicable prospectus supplement may provide that the original issue date for your securities may be more than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the second business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than two scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

The anticipated date of delivery of offered securities will be set forth in the applicable prospectus supplement relating to each offer.

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INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to incorporate by reference the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. Our SEC file number is 000-23695. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede the information already incorporated by reference. We are incorporating by reference the documents listed below, which we have already filed with the SEC, and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, (1) on or after the date of filing of the registration containing this prospectus and prior to the effectiveness of the registration statement and (2) on or after the date of this prospectus until the earlier of the date on which all of the securities registered hereunder have been sold or this registration statement has been withdrawn shall be deemed incorporated by reference in this prospectus and to be a part of this prospectus from the date of filing of those documents:

•

Annual Report on Form 10-K for the fiscal year ended December 31, 2022, filed on February 27, 2023;

•

Quarterly Report on Form 10-Q for the period ended March 31, 2023, filed on May 11, 2023;

•

Current Reports on Form 8-K, filed on January 5, 2023, May 1, 2023 and May 12, 2023;

•

Portions of our Proxy Statement filed on March 31, 2023 that have been incorporated by reference into our Annual Report on Form 10-K; and

•

The description of our common stock contained in our registration statement on Form S-3, filed with the SEC on July 22, 2020, including any amendment or report filed for the purpose of updating such description.

You may request a copy of these filings, and any exhibits we have specifically incorporated by reference as an exhibit in this prospectus, at no cost by writing or telephoning us at the following: Brookline Bancorp, Inc., 131 Clarendon Street, Boston, Massachusetts 02117-9179, Attention: Corporate Secretary. Our telephone number is (617) 425-4600.

This prospectus is part of a registration statement we filed with the SEC. We have incorporated into this registration statement exhibits. You should read the exhibits carefully for provisions that may be important to you.

You should rely only on the information incorporated by reference or provided in this prospectus or any prospectus supplement. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus or in the documents incorporated by reference is accurate as of any date other than the date on the front of this prospectus or those documents.

Any statement contained in a document incorporated by reference in this prospectus shall be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, or in any other document filed later that is also incorporated in this prospectus by reference, modifies or supersedes the statement. Any statement so modified or superseded shall not be deemed to constitute a part of this prospectus except as so modified or superseded. The information relating to us contained in this prospectus should be read together with the information contained in any prospectus supplement and in the documents incorporated in this prospectus and any prospectus supplement by reference.

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WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement under the Securities Act that registers the offer and sale of the securities offered by this prospectus. This prospectus is part of the registration statement, but the registration statement, including the accompanying exhibits included or incorporated by reference therein, contains additional relevant information about us. The rules and regulations of the SEC allow us to omit certain information included in the registration statement from this prospectus.

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are also available to the public from the SEC’s website at http://www.sec.gov and on our website at http://www.brooklinebancorp.com. Except as specifically incorporated by reference in this prospectus, information on those websites is not part of this prospectus.

We have the authority to designate and issue more than one class or series of stock having various preferences, conversion and other rights, voting powers, restrictions, limitations as to dividends, qualifications, and terms and conditions of redemption. See “Description of Common Stock.” We will furnish a full statement of the relative rights and preferences of each class or series of our stock that has been so designated and any restrictions on the ownership or transfer of our stock to any shareholder upon request and without charge. Written requests for such copies should be directed to: Brookline Bancorp, Inc., 131 Clarendon Street, Boston, Massachusetts 02117-9179, Attention: Corporate Secretary.

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PART II
INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The following table sets forth the estimated costs and expenses payable by the registrant in connection with the registration of securities being registered under this Registration Statement. All amounts except the SEC registration fee are estimates.

SEC Registration fee	$	0.00
FINRA Filing Fee		*
Legal fees and expenses		*
Accounting fees and expenses		*
Printing and related expenses		*
Transfer agent and trustee fees and expenses		*
Miscellaneous expenses		*
Total	$	0.00*

Estimated.

Item 15. Indemnification of Directors and Officers.

The following is only a general summary of certain aspects of Delaware law and Brookline’s certificate of incorporation related to the indemnification of directors and officers, and does not purport to be complete. It is qualified in its entirety by reference to the detailed provisions of Sections 145 and 102(b)(7) of the DGCL, and Articles Tenth and Eleventh of Brookline’s certificate of incorporation.

Section 145 of the DGCL generally provides that all directors, officers, employees and agents of a corporation may be indemnified against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement in connection with certain specified actions, suits or proceedings, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation, or a derivative action), if they acted in good faith and in a manner they reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe their conduct was unlawful. A similar standard of care is applicable in the case of derivative actions, except that indemnification extends only to expenses (including attorneys’ fees) incurred in connection with the defense or settlement of an action, and the DGCL requires court approval before there can be any indemnification where the person seeking indemnification has been found liable to the corporation. Section 145 of the DGCL also provides that the rights conferred thereby are not exclusive of any other right to which any person may be entitled under any bylaw, agreement, vote of stockholders or disinterested directors or otherwise, and permits a corporation to advance expenses to or on behalf of a person entitled to be indemnified upon receipt of an undertaking to repay the amounts advanced if it is determined that the person is not entitled to be indemnified.

Article Tenth of Brookline’s certificate of incorporation provides that Brookline will indemnify and hold harmless, to the fullest extent authorized by the DGCL as it presently exists or may be amended, each director or officer who is, or is threatened to be made, a party to or participant in any action, suit or proceeding, whether civil, criminal, administrative or investigative, by reason of the fact that he or she is or was a director or officer of Brookline or is or was serving at the request of Brookline as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust or other enterprise, including service with respect to an employee benefit plan against all expense, liability and loss (including attorneys’ fees, judgments, fines, ERISA excise taxes or penalties and amounts paid in settlement) reasonably incurred or suffered by such person.

Brookline is required to indemnify a person in connection with a proceeding initiated by such person only if the proceeding was authorized by the Brookline board of directors. In addition, Brookline will pay

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the expenses incurred by an officer or director of Brookline in defending any proceeding in advance of its final disposition; provided, however, that the payment of such expenses will be made only upon receipt of an undertaking by the director or officer to repay all amounts advanced if it is ultimately determined that the director or officer is not entitled to be indemnified.

As permitted by Section 102(b)(7) of the DGCL, Brookline’s certificate of incorporation, in Article Eleventh, provides that no director shall be personally liable to Brookline or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director’s duty of loyalty to Brookline or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) for authorizing an unlawful stock purchase, unlawful redemption or unlawful dividend payment, and (iv) for any transaction from which the director derived an improper personal benefit.

As permitted by Section 145(g) of the DGCL, Brookline also maintains a directors’ and officers’ insurance policy which insures the directors and officers of Brookline against liability asserted against such persons in such capacity whether or not such directors or officers have the right to indemnification pursuant to the bylaws or otherwise.

Item 16. Exhibits.

	Exhibit No.			Description
	1.1			Form of Underwriting Agreement*
	1.2			Form of Distribution Agreement (Debt Securities)*
	3.1			Certificate of Incorporation of Brookline Bancorp, Inc. (incorporated by reference to Exhibit 3.1 to the Company’s Annual Report on Form 10-K filed on February 27, 2023)
	3.2			Amended and Restated Bylaws of Brookline Bancorp, Inc. (incorporated by reference to Exhibit 3.02 of the Company’s Current Report on Form 8-K filed on January 10, 2013)
	4.1			Form of Indenture for Senior Debt Securities
	4.2			Form of Indenture for Subordinated Debt Securities
	4.3			Form of Senior Debt Security*
	4.4			Form of Subordinated Debt Security*
	4.5			Form of Warrant Agreement (Stock) (including form of warrant)*
	4.6			Form of Warrant Agreement (Debt) (including form of warrant)*
	4.7			Form of Deposit Agreement for Depositary Shares*
	4.8			Form of Depositary Receipt*
	4.9			Form of Unit Agreement*
	4.10			Form of Unit Certificate*
	4.11			Form of Certificate of Designation of Preferred Stock*
	5.1			Opinion of Goodwin Procter LLP as to the legality of the Securities being registered
	23.1			Consent of Goodwin Procter LLP (included in Exhibit 5.1 hereto)
	23.2			Consent of KPMG LLP, Independent Registered Public Accounting Firm
	24.1			Powers of Attorney (included on signature page of this Registration Statement)
	25.1			Form T-1 Statement of Eligibility of Trustee for Senior Indenture under the Trust Indenture Act of 1939**
	25.2			Form T-1 Statement of Eligibility of Trustee for Subordinated Indenture under the Trust Indenture Act of 1939**
	107			Filing Fee Table

To be filed by amendment or as an exhibit to a document to be incorporated or deemed to be incorporated by reference to this Registration Statement.

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To be filed pursuant to Section 305(b)(2) of the Trust Indenture Act of 1939.

Item 17. Undertakings.

The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i)

to include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii)

to reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Securities and Exchange Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii)

to include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (i), (ii) and (iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Securities and Exchange Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; and

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser,

(i)

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and (B) each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede

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or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date; or

(ii)

each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

(5) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities: The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i)

Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii)

Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii)

The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv)

Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(6) That, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of the securities at that time shall be deemed to be the initial bona fide offering thereof.

(7) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

(8) The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of section 310 of the Trust Indenture Act (“Act”) in accordance with the rules and regulations prescribed by the Commission under section 305(b)(2) of the Act.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and that it has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Commonwealth of Massachusetts, on July 14, 2023.

				BROOKLINE BANCORP, INC.
				By:			/s/ Paul A. Perrault Paul A. Perrault Chairman and Chief Executive Officer (Principal Executive Officer)
				By:			/s/ Carl M. Carlson Carl M. Carlson Co-President, Chief Financial and Strategy Officer (Principal Financial Officer)

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that we, the undersigned officers and directors of Brookline Bancorp, Inc., hereby severally constitute Paul A. Perrault and Carl M. Carlson and each of them singly, our true and lawful attorneys with full power to them, and each of them singly, to sign for us and in our names in the capacities indicated below and in such other capacities as the undersigned may from time to time serve in the future, the registration statement filed herewith and any and all amendments (including post-effective amendments) to said registration statement (or any registration statement for the same offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933, as amended), and generally to do all such things in our names and in our capacities as officers and directors to enable Brookline Bancorp, Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming our signatures as they may be signed by our said attorneys, or any of them, to said registration statement and any and all amendments thereto.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ Paul A. Perrault Paul A. Perrault	Chairman and Chief Executive Officer (Principal Executive Officer)	July 14, 2023
/s/ Carl M. Carlson Carl M. Carlson	Co-President, Chief Financial and Strategy Officer (Principal Financial Officer)	July 14, 2023
/s/ Joseph J. Slotnik Joseph J. Slotnik	Lead Director	July 14, 2023

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	Page
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS		1
PROSPECTUS SUMMARY		2
RISK FACTORS		4
USE OF PROCEEDS		4
THE SECURITIES WE MAY OFFER		5
DESCRIPTION OF DEBT SECURITIES		6
DESCRIPTION OF COMMON STOCK		14
DESCRIPTION OF PREFERRED STOCK		16
DESCRIPTION OF DEPOSITARY SHARES		18
DESCRIPTION OF WARRANTS		21
DESCRIPTION OF UNITS		22
PLAN OF DISTRIBUTION		23
LEGAL MATTERS		26
EXPERTS		26
INFORMATION INCORPORATED BY REFERENCE		27
WHERE YOU CAN FIND MORE INFORMATION		28