Exhibit 4.2


 


EXECUTION VERSION


 


BANKUNITED, INC.


 


as Company,


 


and


 


U.S. BANK NATIONAL ASSOCIATION,


 


as Trustee


 







 



 


FIRST SUPPLEMENTAL INDENTURE


 


Dated as of June 11, 2020 to


 


INDENTURE


 


Dated as of June 11, 2020


 







 



 


5.125% Subordinated Notes due 2030


 






     


     


    

 


TABLE OF CONTENTS




 


	 	 	Page
	 	 	 
	 	Article 1 	 
	 	Definitions	 
	 	 	 
	Section 1.01.	Rules of Construction	1
	Section 1.02.	Definitions	2
	 	 	 
	 	Article 2 	 
	 	General Terms and Conditions of the Subordinated Notes	 
	 	 	 
	Section 2.01.	Designation and Principal Amount	5
	Section 2.02.	Maturity	6
	Section 2.03.	Further Issues	6
	Section 2.04.	Form of Payment	6
	Section 2.05.	Global Securities	6
	Section 2.06.	Interest	6
	Section 2.07.	Discount at Issuance	7
	Section 2.08.	Redemption	7
	Section 2.09.	Appointment of Agents	7
	Section 2.10.	Security	7
	 	 	 
	 	Article 3	 
	 	Form of Notes	 
	 	 	 
	Section 3.01.	Form of Subordinated Notes	7
	 	 	 
	 	Article 4 	 
	 	Original Issue of Notes	 
	 	 	 
	Section 4.01.	Original Issue of Subordinated Notes	7
	 	 	 
	 	Article 5 	 
	 	Additional Terms Applicable to the Subordinated Notes	 
	 	 	 
	Section 5.01.	Replacement of Provisions with Respect to Payment of Interest; Interest Rights Preserved	7
	Section 5.02.	Replacement of Provisions with Respect to Notice of Redemption	7
	Section 5.03.	No Sinking Funds Provisions	8
	Section 5.04.	Replacement of Provisions with Respect to Merger, Consolidation and Sale of Assets	8
	Section 5.05.	Replacement of Provisions with Respect to Statements by Officers as to Events Default	9
	Section 5.06.	Replacement of Provisions with Respect to Events of Default	9


 






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	Section 5.07.	Replacement of Provisions with Respect to Acceleration; Rescission and Annulment	10
	Section 5.08.	Replacement of Provisions with Respect to Other Remedies	11
	Section 5.09.	Replacement of Provisions with Respect to Control by Securityholders; Waiver of Past Defaults	11
	Section 5.10.	Replacement of Provisions with Respect to Limitation on Suits	12
	Section 5.11.	Replacement of Provisions with Respect to Satisfaction and Discharge of Indenture	13
	Section 5.12.	Replacement of Provisions with Respect to Defeasance and Covenant Defeasance upon Deposit of Moneys or U.S. Government Obligations	13
	Section 5.13.	Replacement of Provisions with Respect to Supplemental Indentures	14
	Section 5.14.	Replacement of Provisions with Respect to Supplemental Indentures	15
	Section 5.15.	Replacement of Provisions with Respect to Distribution on Dissolution, Liquidation and Reorganization; Subrogation of Securities	16
	Section 5.16.	Replacement of Provisions with Respect to Distribution on Dissolution, Liquidation and Reorganization; Subrogation of Securities	17
	Section 5.17.	Replacement of Provisions with Respect to Payment on Securities in Event of Default on Senior Indebtedness	17
	 	 	 
	 	Article 6 	 
	 	Miscellaneous	 
	 	 	 
	Section 6.01.	Ratification of Indenture	17
	Section 6.02.	Trustee Not Responsible for Recitals	17
	Section 6.03.	Governing Law	17
	Section 6.04.	Separability	18
	Section 6.05. 	Counterparts	18





 






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FIRST SUPPLEMENTAL INDENTURE, dated
as of June 11, 2020 (this “Supplemental Indenture”), between BankUnited, Inc., a Delaware corporation (the “Company”),
and U.S. Bank National Association, a national banking association, as trustee (the “Trustee”).


 


WHEREAS, the Company and the Trustee
executed and delivered the base indenture, dated as of June 11, 2020 (the “Base Indenture”, as supplemented
by this Supplemental Indenture, the “Indenture”), to provide for the issuance of the Company’s subordinated
debt securities (the “Securities”), to be issued in one or more series;


 


WHEREAS, pursuant to the terms of
the Base Indenture, the Company desires to provide for the establishment of a new series of its notes under the Base Indenture
to be known as its “5.125% Subordinated Notes due 2030” (the “Subordinated Notes”), the form and
substance and the terms, provisions and conditions thereof to be set forth as provided in the Base Indenture and this Supplemental
Indenture;


 


WHEREAS, the Board of Directors of
the Company pursuant to the resolutions duly adopted by the Board of Directors on May 29, 2020 and the resolutions duly adopted
by the Pricing Committee of the Board of Directors on June 4, 2020 have duly authorized the issuance of the Subordinated Notes
and has authorized the proper officers of the Company to execute any and all appropriate documents necessary or appropriate to
effect each such issuance;


 


WHEREAS, this Supplemental Indenture
is being entered into pursuant to the provisions of Section 14.01 of the Base Indenture;


 


WHEREAS, the Company has requested
and hereby requests that the Trustee execute and deliver this Supplemental Indenture; and


 


WHEREAS, all things necessary to
make this Supplemental Indenture a valid and legally binding agreement of the Company, in accordance with its terms, and to make
the Subordinated Notes, when executed by the Company and authenticated and delivered by the Trustee, the valid and legally binding
obligations of the Company, have been performed, and the execution and delivery of this Supplemental Indenture has been duly authorized
in all respects;


 


NOW THEREFORE, in consideration of
the premises and the purchase and acceptance of the Subordinated Notes by the Holders thereof, and for the purpose of setting forth,
as provided in the Base Indenture, the forms and terms of the Subordinated Notes, the Company covenants and agrees, with the Trustee,
as follows:


 


Article
1

Definitions


 


Section 1.01.     
Rules of Construction. In addition to the rules of construction in the introductory paragraph of Article I of the
Base Indenture, except as otherwise


 






     


     


    

 


expressly provided or unless the context otherwise requires, the following provisions shall
also be applied wherever appropriate herein:


 


(a)           
each term defined in the Base Indenture has the same meaning when used in this Supplemental Indenture; provided, however,
that where a term is defined both in this Supplemental Indenture and in the Base Indenture, the meaning given to such term in this
Supplemental Indenture shall control for purposes of (i) this Supplemental Indenture and (ii) in respect of the Subordinated Notes,
but not any other series of Securities, the Base Indenture;


 


(b)           
the singular includes the plural and vice versa;


 


(c)           
headings are for convenience of reference only and do not affect interpretation;


 


(d)           
to the extent any provision of any Subordinated Note conflicts with the express provisions of the Indenture, the provisions
of the Indenture shall govern and be controlling; and


 


(e)           
a reference to a Section or Article is to a Section or Article of this Supplemental Indenture unless otherwise indicated.


 


Section 1.02.     
Definitions. Unless the context otherwise requires, the following terms have the meanings given to them in this Section
1.02:


 


(i)           
“1940 Act Event,” means the Company becoming required to register as an investment company pursuant to
the Investment Company Act of 1940, as amended.


 


(ii)           
“Bankruptcy Law” means title 11, U.S. Code or any similar federal or state law for the relief of debtors.


 


(iii)           
“Bankruptcy Custodian” means any receiver, trustee, assignee, liquidator or other similar official under
any Bankruptcy Law.


 


(iv)           
 “Business Day” means any Monday, Tuesday, Wednesday, Thursday or Friday that is not a day on which banking
institutions in New York, New York or the place of payment with respect to the Subordinated Notes are authorized or required by
law or executive order to close.


 


(v)           
“Capital Stock” of any Person means any and all shares, interests, rights to purchase, warrants, options,
participations or other equivalents of, or interests in (however designated), equity of such Person, including preferred stock,
but excluding any debt securities convertible into such equity.


 


(vi)           
“Senior Indebtedness” means the principal of, premium, if any, and interest (including interest accruing
on or after the filing of any petition in bankruptcy or for reorganization relating to the Company) on and any other


 






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payment due
pursuant to any of the following, whether incurred on or prior to the date hereof or hereafter incurred:


 


(a)   
all obligations of the Company (other than obligations pursuant to any other Subordinated Notes issued under the Indenture)
for money borrowed;


 


(b)  
all obligations of the Company evidenced by securities, notes, debentures, bonds or other similar instruments (other than
any Subordinated Notes issued under the Indenture), including obligations incurred in connection with the acquisition of property,
assets or businesses;


 


(c)   
all capital lease obligations of the Company;


 


(d)  
all obligations of the Company arising from off-balance sheet guarantees and direct credit substitutes, including obligations
in respect of any letters of credit, banker’s acceptance, security purchase facilities and similar credit transactions;


 


(e)   
all obligations to general creditors of the Company;


 


(f)    
all obligations of the Company issued or assumed as the deferred purchase price of property or services, including all obligations
under master lease transactions pursuant to which the Company or any of its Subsidiaries has agreed to be treated as owner of the
subject property for U.S. federal income tax purposes;


 


(g)  
all obligations of the Company associated with derivative products including, but not limited to, securities contracts,
foreign currency exchange contracts, swap agreements (including interest rate and foreign exchange rate swap agreements), cap agreements,
floor agreements, collar agreements, interest rate agreements, foreign exchange rate agreements, options, commodity futures contracts,
commodity option contracts and similar financial instruments; and


 


(h)  
all obligations of the type referred to in clauses (a) through (g) of this definition of another Person the payment of which,
in either case, the Company has assumed or guaranteed or for which the Company is responsible or liable, directly or indirectly,
jointly or severally, as obligor, guarantor or otherwise;


 


provided that “Senior
Indebtedness” shall not include (i) any Capital Stock of the Company, (ii) any obligations to trade creditors created or
assumed by the Company in the ordinary course of business, (iii) any obligation of the Company to any Subsidiary of the Company
or to any Person with respect to which the Company is a Subsidiary, and (iv) any indebtedness that (x) expressly states that it
is junior to or ranks


 






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equally in right of payment with the Subordinated Notes, (y) is identified as junior to, or equal in right
of payment with, the Subordinated Notes in any board resolution establishing such indebtedness (or otherwise approving the assumption
or issuance of such Indebtedness by the Company) or in any supplemental indenture or (z) which is subordinated to indebtedness
of the Company to substantially the same extent as, or to a greater extent than, the Subordinated Notes are subordinated.


 


Notwithstanding the foregoing,
if the Federal Reserve (or other competent regulatory agency or authority) promulgates any rule or issues any interpretation that
defines general creditor(s), the main purpose of which is to establish criteria for determining whether the subordinated debt of
a bank holding company is to be included in its capital, then the term ‘‘general creditors’’ as used in
this definition of “Senior Indebtedness” will have the meaning as described in that rule or interpretation.


 


Notwithstanding anything in the
Indenture to the contrary, Senior Indebtedness will continue to be Senior Indebtedness and entitled to the benefits of the subordination
provisions of the Indenture irrespective of any amendment, modification or waiver of any term of the Senior Indebtedness or extension
or renewal of the Senior Indebtedness.


 


(vii)           
“Default” means any Event of Default or events which, after notice or lapse of time or both would become,
an Event of Default.


 


(viii)           
“Issue Date” means the date on which the Subordinated Notes are first issued.


 


(ix)           
“Payment or Covenant Event of Default” has the meaning assigned to such term in Section 7.01 of the Base
Indenture as amended by this Supplemental Indenture.


 


(x)           
 “Subsidiary” means, with respect to any specified Person: (1)any corporation, association or other
business entity of which more than 50% of the total voting power of shares of Capital Stock entitled (without regard to the occurrence
of any contingency and after giving effect to any voting agreement or stockholders’ agreement that effectively transfers
voting power) to vote in the election of directors, managers or trustees of the corporation, association or other business entity
is at the time owned or controlled, directly or indirectly, by that Person or one or more of the other Subsidiaries of that Person
(or a combination thereof); and (2) any partnership (a) the sole general partner or the managing general partner of which is such
Person or a Subsidiary of such Person or (b) the only general partners of which are that Person or one or more Subsidiaries of
that Person (or any combination thereof).


 






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(xi)           
 “Tax Event” means the Company’s good-faith determination that, as a result of: (a) an amendment
to or change (including any announced prospective amendment or change) in any law or treaty, or any regulation thereunder, of the
United States or any of its political subdivisions or taxing authorities; (b) a judicial decision, administrative action, official
administrative pronouncement, ruling, regulatory procedure, regulation, notice or announcement (any of the foregoing, an “administrative
or judicial action”); or (c) an amendment to or change in any official position with respect to, or any interpretation
of, an administrative or judicial action or a law or regulation of the United States that differs from the previously generally
accepted position or interpretation, in each case, which amendment or change becomes effective or which administrative or judicial
action is taken, announced or issued on or after the original issue date of the Subordinated Notes, there is more than an insubstantial
risk that interest payable by the Company on the Subordinated Notes is not, or, within 90 days of the date of such determination,
will not be, deductible by the Company, in whole or in part, for United States federal income tax purposes.


 


(xii)           
“Tier 2 Capital Event” means the Company’s good-faith determination that, as a result of: (a) any
amendment to, or change in, the laws, rules, or regulations of the United States (including, for the avoidance of doubt, any agency
or instrumentality of the United States, including the Federal Reserve and other federal bank regulatory agencies) or any political
subdivision of or in the United States that is enacted or becomes effective after the original issue date of the Subordinated Notes;
(b) any proposed change in those laws, rules or regulations that is announced or becomes effective after the original issue date
of the Subordinated Notes; or (c) any official administrative decision or judicial decision or administrative action or other official
pronouncement interpreting or applying those laws, rules, regulations, policies, or guidelines with respect thereto that is announced
after the original issue date of the Subordinated Notes, there is more than an insubstantial risk that the Company will not be
entitled to treat the Subordinated Notes then Outstanding as “Tier 2 Capital” (or its equivalent) for purposes of the
capital adequacy rules or regulations of the Federal Reserve (or any successor appropriate federal banking agency) as then in effect
and applicable to the Company, for so long as any Subordinated Notes are Outstanding.


 


Article
2

General Terms and Conditions of the Subordinated Notes


 


Section 2.01.     
Designation and Principal Amount. There is hereby authorized and established a new series of Securities under the
Base Indenture, designated as the “5.125% Subordinated Notes due 2030,” which is not limited in aggregate principal
amount. The initial aggregate principal amount of the Subordinated Notes to be issued under this Supplemental Indenture shall be
limited to $300,000,000. Any additional amounts of Subordinated Notes to be issued shall be set forth in a Company Order.


 






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Section 2.02.     
Maturity. The stated maturity of principal for the Subordinated Notes will be June 11, 2030.


 


Section 2.03.     
Further Issues. The Company may from time to time, without the consent of the Holders of the Subordinated Notes,
issue additional Subordinated Notes in an unlimited aggregate principal amount. Any such additional notes will have the same ranking,
interest rate, Stated Maturity and other terms as the Subordinated Notes, except for any differences in the issue date and, in
certain cases, the issue price and the first interest payment date, either of which may differ from the respective terms of any
previously issued Subordinated Notes. The Subordinated Notes and any such additional notes subsequently issued under the Indenture
would be treated as a single series of Securities for all purposes under the Indenture, including, without limitation, waivers,
amendments, redemptions and offers to purchase; provided, that if any such additional notes subsequently issued under the
Indenture are not fungible for U.S. federal income tax purposes with the Subordinated Notes, such additional notes shall trade
separately from the Subordinated Notes under a separate CUSIP number, but shall otherwise be treated as a single series with the
Subordinated Notes and all other such additional notes issued under the Indenture.


 


Section 2.04.     
Form of Payment. Principal of, premium, if any, and interest on the Subordinated Notes shall be payable in U.S. dollars.


 


Section 2.05.     
Global Securities. Upon the original issuance, the Subordinated Notes will be represented by one or more Global Securities.
The Company will issue the Subordinated Notes in denominations of $2,000 and in integral multiples of $1,000 in excess thereof
and will deposit the Global Securities with the Trustee as custodian for The Depository Trust Company (“DTC”),
in New York, New York, and register the Global Securities in the name of DTC or its nominee.


 


Section 2.06.     
Interest. The Subordinated Notes will bear interest at an annual rate equal to 5.125%. Interest on the Subordinated
Notes will be payable semi-annually in arrears on June 11 and December 11 of each year (each such date, an “Interest Payment
Date”), beginning on December 11, 2020, to the holders of record at the close of business on the preceding May 28 and
November 27 of each year. Interest on the Subordinated Notes will be computed on the basis of a 360-day year comprised of twelve
30-day months. Interest payments on the Subordinated Notes will be the amount of interest accrued from, and including, June 11,
2020 or the most recent Interest Payment Date on which interest has been paid to, but excluding, the Interest Payment Date or the
Stated Maturity, as the case may be.


 


If an Interest Payment Date, Redemption
Date or the Stated Maturity falls on a day that is not a Business Day, the related payment of interest and principal will be made
on the next day that is a Business Day, and no interest on the Subordinated Notes or such payment will accrue for the period from
and after such Interest Payment Date, Redemption Date or Stated Maturity, as the case may be.


 






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Section 2.07.     
Discount at Issuance. The Subordinated Notes issued on the date hereof are being purchased at the purchase price
therefor set forth in that certain Underwriting Agreement, dated as of June 4, 2020, by and among the Company and BofA Securities,
Inc., J.P. Morgan Securities LLC and Piper Sandler & Co., as Representatives of the Underwriters identified therein.


 


Section 2.08.     
Redemption. The Subordinated Notes are subject to redemption at the option of the Company as set forth in the form
of Subordinated Notes attached hereto as Exhibit A.


 


Section 2.09.     
Appointment of Agents. The Trustee will initially be the Registrar and Paying Agent for the Subordinated Notes.


 


Section 2.10.     
Security. The Subordinated Notes will not be secured, as of the time of their original issuance.


 


Article
3

Form of Notes


 


Section 3.01.     
Form of Subordinated Notes. The Subordinated Notes, and the Trustee’s Certificate of Authentication to be endorsed
thereon, are to be substantially in the form set forth in Exhibit A hereto.


 


Article
4

Original Issue of Notes


 


Section 4.01.     
Original Issue of Subordinated Notes. The Subordinated Notes may, upon execution of this Supplemental Indenture,
be executed by the Company and delivered to the Trustee for authentication, and the Trustee shall, upon Company order, authenticate
and deliver such Subordinated Notes as in such Company order provided.


 


Article
5

Additional Terms Applicable to the Subordinated Notes


 


Section 5.01.     
Replacement of Provisions with Respect to Payment of Interest; Interest Rights Preserved. The second sentence of
Section 3.08(a) of the Base Indenture is hereby replaced in its entirety with the following:


 


If a Holder of Subordinated Notes has
given wire transfer instructions to the Company, the Company will pay all principal, interest, and premium, if any, on that Holder’s
Subordinated Notes in accordance with those instructions. All other payments on the Subordinated Notes will be made at the office
or agency of the Paying Agent and registrar within the City and State of New York, unless the Company elects to make interest payments
by check mailed to the Holders of the Subordinated Notes at their address set forth in the register of Holders.


 


Section 5.02.     
Replacement of Provisions with Respect to Notice of Redemption.


 






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(a)           
Section 4.02(a) of the Base Indenture is hereby replaced in its entirety with the following:


 


If the Company shall at any time
elect to redeem all or any portion of the Securities of a series then Outstanding, it shall at least 10 days prior to the date
notice of redemption is to be sent to Holders (unless a shorter period shall be satisfactory to the Trustee) notify the Trustee
of such Redemption Date and of the principal amount of Securities to be redeemed, and thereupon the Trustee shall select, by lot
or in accordance with DTC’s applicable procedures; provided that the unredeemed portion of the principal amount of any Security
shall be in an authorized denomination (which shall not be less than the minimum authorized denomination) for such Security. In
any case where more than one Security of such series is registered in the same name, the Trustee may treat the aggregate principal
amount so registered as if it were represented by one Security of such series. The Trustee shall, as soon as practicable, notify
the Company in writing of the Securities and portions of Securities so selected.


 


(b)           
Section 4.03(a) of the Base Indenture is hereby amended in part by replacing the first sentence with the following:


 


Notice of redemption shall be given
by the Company or, at the Company’s request and provision of such notice, by the Trustee in the name and at the expense
of the Company, at least 10 but not more than 60 days prior to the Redemption Date, to each Holder of Subordinated Notes to
be redeemed at its registered address pursuant to this Article, in the manner provided in Section 16.04; provided that
notice of redemption may be so given more than 60 days prior to the Redemption Date if such notice is issued in connection
with a satisfaction and discharge of the Indenture.


 


Section 5.03.     
No Sinking Funds Provisions. Article 5 of the Base Indenture shall not apply to the Subordinated Notes.


 


Section 5.04.     
Replacement of Provisions with Respect to Merger, Consolidation and Sale of Assets. Section 6.04 of the Base Indenture
is hereby replaced in its entirety with the following:


 


(a)           
The Company may not consolidate with or merge into, or sell, convey, transfer or lease all or substantially all our assets,
including properties, to, any other Person, unless:


 


(i)           
either (i) the Company shall be the continuing entity, or (ii) the successor, transferee or lessee Person (if other than
the Company) is a Person validly existing under the laws of the United States or any state thereof or the District of Columbia
and expressly assumes, by supplemental indenture, executed and delivered by such Person prior to or simultaneously with such consolidation,
merger, sale, conveyance, transfer or lease, the due and punctual payment of the principal of and interest and premium, if any,
on all the Subordinated Notes, according to their tenor, and the due and punctual performance and observance of


 



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all other obligations
to the Holders of the Subordinated Notes and the Trustee to be performed or observed by the Company under the Indenture; and


 


(ii)           
immediately after giving effect to the transaction, no Default or Event of Default under the Indenture shall have occurred
and be continuing.


 


(b)           
Upon any such consolidation or merger, or sale, conveyance, transfer or lease in accordance with the Indenture, the successor
Person formed, or into which the Company is merged or to which such sale, conveyance, transfer or lease is made, shall succeed
to, and be substituted for, and may exercise every right and power of, the Company under the Indenture with the same effect as
if such successor Person had been named as a party thereto, and thereafter, except in the case of a lease, the Company shall be
relieved of all obligations and covenants under the Indenture and the Subordinated Notes, and from time to time such Person may
exercise each and every right and power of the Company under the Indenture, in the Company’s name, or in its own name; and
any act or proceeding by any provision of the Indenture required or permitted to be done by the Company’s board of directors
or any of the Company’s officers may be done with like force and effect by the like board or officer of any entity that shall
at the time be the Company’s successor thereunder. In the event of any such sale or conveyance, but not any such lease, the
Company (or any successor entity which shall theretofore have become such in the manner described in this Section 6.04) shall be
discharged from all obligations and covenants under the Indenture and the Subordinated Notes and may thereupon be dissolved and
liquidated.


 


(c)           
This Section 6.04 of the Indenture will not apply to: (i) a merger of the Company with an Affiliate solely for the purpose
of reincorporating the Company in another jurisdiction; or (ii) any consolidation or merger, or any sale, assignment, transfer,
conveyance, lease or other disposition of assets between or among the Company and its Subsidiaries.


 


Section 5.05.     
Replacement of Provisions with Respect to Statements by Officers as to Events Default. Section 6.07 of the Base Indenture
is hereby replaced in its entirety with the following:


 


The Company shall deliver to the Trustee
as soon as possible and in any event within 30 days after the Company becomes aware of the occurrence of any Event of Default or
Default, an Officer's Certificate setting forth the details of such Event of Default or Default and the action which the Company
proposes to take with respect thereto.


 


Section 5.06.     
Replacement of Provisions with Respect to Events of Default. Section 7.01 of the Base Indenture is hereby replaced
in its entirety with the following:


 


The following are defined as “Events
of Default” with respect to the Subordinated Notes:


 






    9


     


    

 


(a)           
default is made in the payment of any installment of interest on any Subordinated Note when such interest shall have become
due and payable and such default continues for a period of 30 days;


 


(b)           
default is made in the payment of the principal of or any premium on any Subordinated Note at its maturity or upon any redemption
or by declaration or otherwise;


 


(c)           
default is made in the performance of any covenant of the Company that applies to the Subordinated Notes in the Indenture
or any Subordinated Note, and continuance of such default for a period of 90 days after there has been given, by registered or
certified mail, to the Company by the Trustee or to the Company and the Trustee by the Holders of at least 25% in principal amount
of Outstanding Subordinated Notes a written notice specifying such default and requiring it to be remedied and stating that such
notice is a “Notice of Default” under the Indenture (each of the Events of Default described in the foregoing clauses
(a), (b) and (c), a “Payment or Covenant Event of Default”);


 


(d)           
 [Reserved];


 


(e)           
a court of competent jurisdiction enters an order or decree under any applicable Bankruptcy Law that:


 


(i)           
is for relief against the Company in an involuntary case; or


 


(ii)           
appoints a Bankruptcy Custodian of the Company or for all or substantially all of the property of the Company; or


 


(iii)           
orders the liquidation of the Company,


 


and, in each case, the order or
decree remains unstayed and in effect for 90 consecutive days; or


 


(f)            
the commencement by the Company of a voluntary proceeding under any applicable Bankruptcy Law or the consent by the Company
to the entry of a decree or order for relief in an involuntary proceeding under any applicable Bankruptcy Law, or the consent by
the Company to the appointment of or taking possession by a custodian, receiver, liquidator, assignee, trustee or similar official
of the Company or of all or substantially all of the property of the Company, or the making by the Company of an assignment for
the benefit of creditors, or the admission in writing by the Company of its inability to pay its debts generally as they become
due.


 


Section 5.07.     
Replacement of Provisions with Respect to Acceleration; Rescission and Annulment. The first sentence of Section 7.02(a)
of the Base Indenture is hereby replaced in its entirety with the following:


 


In the case of an Event of Default
that is a Payment or Covenant Event of Default, neither the Trustee nor the Holders of Subordinated Notes may act to accelerate
the maturity of the Subordinated Notes. In such case, the Trustee may proceed to enforce any


 






    10


     


    

 


covenant and other rights of the Holders
of the Subordinated Notes. For the avoidance of doubt, there is no right of acceleration in the case of a default in the payment
of principal of, premium (if any), or interest on the Subordinated Notes or in case of the Company’s nonperformance of any
other covenant under the Subordinated Notes or the Indenture.


 


Section 5.08.     
Replacement of Provisions with Respect to Other Remedies. Section 7.03 of the Base Indenture is hereby replaced in
its entirety with the following:


 


If any Payment or Covenant Event
of Default shall occur that relates to the Company’s failure to make any payment of interest due and payable, and such Payment
or Covenant Event of Default continues for 30 days or such Payment or Covenant Event of Default is made in the payment of the principal
or any premium at its Maturity, then the Trustee may demand payment of the amounts then due and payable and may proceed to prosecute
any failure on the Company’s part to make such payments (including by recovering judgment, in its own name and as trustee
of an express trust, against the Company for the whole amount of such payments). Every recovery of judgment in any such action
or other proceeding, subject to the payment to the Trustee of all amounts owing the Trustee and any predecessor trustee hereunder
under ‎Section 11.01(a), shall be for the ratable benefit of the Holders of such series of Securities which shall be
the subject of such action or proceeding. All rights of action upon or under any of the Securities or this Indenture may be enforced
by the Trustee without the possession of any of the Securities and without the production of any thereof at any trial or any proceeding
relative thereto.


 


Section 5.09.     
Replacement of Provisions with Respect to Control by Securityholders; Waiver of Past Defaults. Section 7.06 of the
Base Indenture is hereby replaced in its entirety with the following:


 


The Holders of a majority in principal
amount of the Subordinated Notes at the time Outstanding may direct the time, method and place of conducting any proceeding for
any remedy available to the Trustee hereunder, or of exercising any trust or power hereby conferred upon the Trustee with respect
to the Subordinated Notes, provided, however, that, subject to the provisions of Sections 11.01 and 11.02
in the Indenture, the Trustee shall have the right to decline to follow any such direction if the Trustee being advised by counsel
determines that the action so directed may not lawfully be taken or would be unduly prejudicial to Holders not joining in such
direction or would involve the Trustee in personal liability. The Holders of a majority in aggregate principal amount of the then-Outstanding
Subordinated Notes by notice to the Trustee may, on behalf of the Holders of all of the Subordinated Notes, rescind an acceleration
or waive any existing Default or Event of Default and its consequences under the Indenture except a continuing Event of Default
in the payment of interest or premium, if any, on, or the principal of, the Subordinated Notes and except as to a covenant or
condition which under ‎Section 14.02 cannot be modified or amended without the consent of the Holder of each Outstanding
Subordinated Note, in which case the consent of the Holder of each Outstanding Subordinated Note shall be required for such waiver.
Upon any such waiver the


 






    11


     


    

 


Company, the Trustee and
the Holders of the Subordinated Notes shall be restored to their former positions and rights hereunder, respectively; but no such
waiver shall extend to any subsequent or other Default or Event of Default or impair any right consequent thereon. Whenever any
Default or Event of Default hereunder shall have been waived as permitted by this Section 7.06, said Default or Event of Default
shall for all purposes of the Subordinated Notes and this Indenture be deemed to have been cured and to be not continuing. For
the avoidance of doubt, any consent provided by Holders in connection with a waiver as permitted by this Section 7.06 shall include,
without limitation, consents obtained in connection with a purchase of, or tender offer or exchange offer for, Subordinated Notes.


 


Section 5.10.     
Replacement of Provisions with Respect to Limitation on Suits. Section 7.07 of the Base Indenture is hereby replaced
in its entirety with the following:


 


Subject to the provisions of the Indenture
relating to the duties of the Trustee, if an Event of Default occurs and is continuing, the Trustee will be under no obligation
to exercise any of the rights or powers under the Indenture at the request or direction of any Holders of Subordinated Notes unless
such Holders have offered to the Trustee reasonable indemnity or security against any loss, liability or expense. Except to enforce
the right to receive payment of principal, premium, if any, or interest, when due, no Holder of Subordinated Notes may pursue any
remedy with respect to the Indenture or the Subordinated Notes unless:


 


(a)           
such Holder has previously given the Trustee notice that an Event of Default is continuing;


 


(b)           
Holders of at least 25% in aggregate principal amount of the then-Outstanding Subordinated Notes have requested the Trustee
to pursue the remedy;


 


(c)           
such Holders have offered the Trustee reasonable security or indemnity against any loss, liability or expense;


 


(d)           
the Trustee has not complied with such request within 60 days after the receipt of the request and the offer of security
or indemnity; and


 


(e)           
Holders of a majority in aggregate principal amount of the then-Outstanding Subordinated Notes have not given the Trustee
a direction inconsistent with such request within such 60-day period;


 


it being understood and intended that no one or more of the
Holders of Subordinated Notes shall have any right in any manner whatsoever by his, her, its or their action to enforce any right
hereunder, except in the manner herein provided, and that every action, suit or proceeding at law or in equity shall be instituted,
had and maintained in the manner herein provided and for the equal benefit of all Holders of the Outstanding Subordinated Notes;
provided, however, that nothing in this Section or this Indenture or in the Subordinated Notes shall affect or impair the
obligation of the Company, which is absolute and unconditional, to pay the principal of, premium, if any, and interest on the Subordinated
Notes to the respective Holders of such Subordinated Notes at the


 






    12


     


    

 


respective due dates in such Subordinated Notes stated, or affect
or impair the right, which is also absolute and unconditional, of such Holders to institute suit to enforce the payment thereof.


 


Section 5.11.     
Replacement of Provisions with Respect to Satisfaction and Discharge of Indenture. The first sentence of Section
12.02 of the Base Indenture is hereby replaced in its entirety with the following:


 


The Indenture will, upon Company Order,
cease to be of further effect as to all Subordinated Notes (except as to any surviving rights of registration of transfer or exchange
of such Subordinated Notes herein expressly provided for and the rights of the Holders of the Subordinated Notes to receive the
principal of and premium, if any, and interest on such Subordinated Notes as and when the same shall become due and payable and
except as otherwise provided in the last paragraph of this Section 12.02), and the Trustee, at the expense of the Company, shall
execute proper instruments acknowledging satisfaction and discharge of this Indenture with respect to the Subordinated Notes, when:


 


(a)           
either:


 


(i)           
all Subordinated Notes theretofore authenticated and delivered (other than (A) Subordinated Notes that have been destroyed,
lost or stolen and that have been replaced or paid as provided in Section 3.07 and (B) Subordinated Notes for whose payment money
has theretofore been deposited in trust or segregated and held in trust by the Company and thereafter repaid to the Company or
discharged from trust, as provided in Section 6.03(e)), have been delivered to the Trustee for cancellation; or


 


(ii)           
all Subordinated Notes that have not been delivered to the Trustee for cancellation (A) have become due and payable, or
(B) will become due and payable at their stated maturity within one year, or (C) are to be called for redemption within one year
under arrangements satisfactory to the Trustee for the giving of notice of redemption by the Trustee in the name, and at the expense
of the Company, and the Company, in the case of (A), (B) or (C) above has irrevocably deposited or caused to be deposited with
the Trustee funds in trust for the purpose an amount in cash in U.S. dollars sufficient to pay and discharge the entire indebtedness
on such Subordinated Notes for principal, premium, if any, and accrued interest to the date of maturity or redemption;


 


(b)           
The Company paid or caused to be paid all sums payable by it under the Indenture with respect to the Subordinated Notes;
and


 


(c)           
The Company has delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel each stating that all
conditions precedent in the Indenture relating to the satisfaction and discharge of the Indenture with respect to the Subordinated
Notes have been complied with.


 


Section 5.12.     
Replacement of Provisions with Respect to Defeasance and Covenant Defeasance upon Deposit of Moneys or U.S. Government
Obligations.


 






    13


     


    

 


(a)           
Section 12.03(a) of the Base Indenture is hereby replaced in its entirety with the following:


 


the Company shall have deposited
or caused to be deposited irrevocably with the Trustee as trust funds in trust, and dedicated solely to, the benefit of the Holders
of the Securities of such series (i) money in the Currency in which such Securities are payable in an amount, or (ii) U.S. Government
Obligations (as defined below) that, through the payment of interest and principal in respect thereof in accordance with their
terms, will provide, not later than one day before the due date of any payment, money in the Currency in which such Securities
are payable in an amount, or (iii) a combination of ‎(i) and ‎(ii), sufficient (in the case of clauses (ii)
or (iii), in the opinion of a nationally recognized firm of independent certified public accountants), without consideration of
any reinvestment of such principal and interest, to pay and discharge each installment of principal (including any mandatory sinking
fund payments) of and premium, if any, and interest on, the Outstanding Securities of such series on the dates such installments
of interest or principal and premium are due and, if the Securities of such series are to be called for redemption as described
in clause ‎(d) below, to pay and discharge the Redemption Price on the Securities called for redemption on the applicable
Redemption Date;


 


(b)           
Section 12.03(c) of the Base Indenture is hereby amended by adding the following words immediately prior to the semicolon
at the end thereof: “or shall be based upon a change in the applicable federal income tax law after the original issue date
of the Subordinated Notes”.


 


Section 5.13.     
Replacement of Provisions with Respect to Supplemental Indentures. The first sentence of Section 14.01 of the Base
Indenture is hereby replaced in its entirety with the following:


 


Notwithstanding Section 14.02, the
Company and the Trustee, at any time and from time to time, may amend or supplement the Indenture and the Subordinated Notes (including
pursuant to one or more indentures supplemental hereto) for any one or more of or all the following purposes without the consent
of any Holder of the Subordinated Notes:


 


(a)           
to cure any ambiguity, defect, or inconsistency;


 


(b)           
to provide for uncertificated Subordinated Notes in addition to or in place of certificated Subordinated Notes or to provide
for the issuance of bearer notes (with or without coupons);


 


(c)           
to add to the covenants of the Company for the benefit of the Holders of Subordinated Notes or surrender any right or power
conferred upon the Company in the Indenture or the Subordinated Notes;


 






    14


     


    

 


(d)           
to add additional events of default for the benefit of the Holders of Subordinated Notes;


 


(e)           
to provide any security for, or add any additional obligors on, the Subordinated Notes;


 


(f)            
to evidence and provide for the acceptance of appointment by a successor trustee with respect to the Subordinated Notes,
and add to or change any provision as shall be necessary to provide for or facilitate the administration of the trusts by more
than one trustee;


 


(g)           
to comply with the rules or regulations of any securities exchange or automated quotation system on which any of the Subordinated
Notes may be listed or traded;


 


(h)           
to supplement any provision to such extent as shall be necessary to permit or facilitate the defeasance and discharge of
the Subordinated Notes in accordance with the Indenture, provided that such action shall not adversely affect the interest of the
Holders of the Subordinated Notes in any material respect;


 


(i)            
to provide for the assumption of the Company’s obligations to Holders of Subordinated Notes in the case of a merger
or consolidation or sale of all or substantially all of the Company’s assets;


 


(j)            
to make any change that would provide any additional rights or benefits to the Holders of Subordinated Notes, increase the
interest rate applicable to Subordinated Notes, or that does not adversely affect in any material respect the legal rights under
the Indenture of any such Holder;


 


(k)           
to comply with requirements of the SEC in order to effect or maintain the qualification of the Indenture under the Trust
Indenture Act;


 


(l)            
to conform the text of the Indenture or the Subordinated Notes to any provision set forth under the caption “Description
of Notes” in the prospectus supplement filed with the SEC on June 4, 2020; and


 


(m)            
to provide for the issuance of additional Subordinated Notes in accordance with the limitations, if any, set forth in the
Indenture as of the date hereof.


 


Section 5.14.     
Replacement of Provisions with Respect to Supplemental Indentures. Section 14.02(a) of the Base Indenture is hereby
replaced in its entirety with the following:


 


(a) With the consent of the Holders
(evidenced as provided in Article VIII) of a majority in aggregate principal amount of the Outstanding Subordinated Notes, which
consent may include, without limitation, consents obtained in connection with a purchase of, or tender offer or exchange offer
for, Subordinated Notes, the Company and the Trustee may, from time to time and at any time, enter into an indenture or indentures


 






    15


     


    

 


supplemental hereto for the purpose of adding any provisions to or changing in any manner or eliminating any provisions of this
Indenture or of modifying in any manner the rights of the Holders of the Subordinated Notes to be affected; provided, however,
that without the consent of each Holder of Outstanding Subordinated Notes, no such supplemental indenture shall (with respect to
any Subordinated Notes held by a non-consenting Holder),


 


(i)           
reduce the principal amount of Subordinated Notes whose Holders must consent to an amendment, supplement, or waiver;


 


(ii)           
reduce the principal of or change the fixed maturity of any Subordinated Notes or reduce the redemption price of any Subordinated
Notes;


 


(iii)           
reduce the rate of or change the time for payment of interest, including default interest, on any Subordinated Notes;


 


(iv)           
waive a Default or Event of Default in the payment of principal of, or interest, or premium, if any, on, the Subordinated
Notes (except, to the extent applicable, a rescission of acceleration of the Subordinated Notes by the Holders of at least a majority
in aggregate principal amount of the then-Outstanding Subordinated Notes and a waiver of the payment default that resulted from
such acceleration);


 


(v)           
make the Subordinated Notes payable in money other than U.S. dollars;


 


(vi)           
impair the right of any Holder of Subordinated Notes to institute suit for the enforcement of any payment on or with respect
to the Subordinated Notes; or


 


(vii)           
make any change in this Section 14.02(a), Section 7.06 or Section 6.06.


 


Section 5.15.     
Replacement of Provisions with Respect to Distribution on Dissolution, Liquidation and Reorganization; Subrogation of
Securities. Section 15.02 of the Base Indenture is hereby amended in part to replace the first paragraph thereof with the following
text:


 


In the event of (i) any insolvency,
bankruptcy, receivership, liquidation, reorganization, or other similar case or proceeding pursuant to any Bankruptcy Law, or any
proceeding in connection therewith, relative to the Company or to its assets, (ii) any liquidation, dissolution or other winding
up of the Company, whether voluntary or involuntary and whether or not involving insolvency or bankruptcy, or (iii) any assignment
for the benefit of creditors or any other marshalling of assets or liabilities of the Company:


 






    16


     


    

 


Section 5.16.     
Replacement of Provisions with Respect to Distribution on Dissolution, Liquidation and Reorganization; Subrogation of
Securities. Section 15.02(c) of the Base Indenture is hereby replaced in its entirety with the following:


  


(a)           
if the Company makes a payment or distribution to Holders of the Subordinated Notes before the Company has paid all of the
Senior Indebtedness in full, then such Holders of the Subordinated Notes shall pay or transfer the payments or distributions to
the trustee in bankruptcy, receiver, liquidating trustee or other person distributing the Company’s assets for payment of
the Senior Indebtedness.


 


Section 5.17.     
Replacement of Provisions with Respect to Payment on Securities in Event of Default on Senior Indebtedness. The first
sentence of the first paragraph of Section 15.03 of the Base Indenture is hereby replaced in its entirety with the following:


 


Unless all principal of and any premium
or interest on all Senior Indebtedness has been paid in full, no payment or other distribution may be made in respect of any Subordinated
Notes in the following circumstances:(i) either (a) in the event and during the continuation of any default in the payment of principal
of, or premium (if any) or interest on any Senior Indebtedness beyond any applicable grace period or (b) in the event that any
event of default with respect to any Senior Indebtedness has occurred and is continuing, permitting the direct holders of that
Senior Indebtedness (or a trustee or other authorized party on their behalf) to accelerate the maturity of that Senior Indebtedness,
whether or not the maturity is in fact accelerated (unless, in the case of either (i)(a) or (i)(b), the default or event of default
described therein has been cured or waived or ceased to exist and any related acceleration has been rescinded), and (ii) either
(a) any default or event of default described in clause (i)(a) or (i)(b) is the subject of a judicial proceeding or (b) the Company
or the Trustee receives notice of such default or event of default from the indenture trustee or other trustee, agent or representative
(if any) for the applicable issue of Senior Indebtedness (or, if there is no such indenture trustee, other trustee, agent or representative
of such issue, then the holder thereof).


 


Article
6

Miscellaneous


 


Section 6.01.     
Ratification of Indenture. The Base Indenture, as supplemented by this Supplemental Indenture, is in all respects
ratified and confirmed, and this Supplemental Indenture shall be deemed part of the Base Indenture in the manner and to the extent
herein and therein provided; provided that the provisions of this Supplemental Indenture apply solely with respect to the Subordinated
Notes.


 


Section 6.02.     
Trustee Not Responsible for Recitals. The recitals and statements herein contained are made by the Company and not
by the Trustee, and the Trustee assumes no responsibility for the correctness thereof. The Trustee makes no representation as to
the validity or sufficiency of this Supplemental Indenture.


 


Section 6.03.     
Governing Law. This Supplemental Indenture and each Senior Note shall be deemed to be contracts made under the law
of the State of New York, and


 






    17


     


    

 


for all purposes shall be governed by and construed in accordance with the law of said State.


 


Section 6.04.     
Separability. In case any provision in the Indenture or in the Subordinated Notes shall be invalid, illegal or unenforceable,
the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.


 


Section 6.05.     
Counterparts. This Supplemental Indenture may be executed in any number of counterparts each of which shall be an
original; but such counterparts shall together constitute but one and the same instrument. The exchange of copies of this Supplemental
Indenture and of signature pages by facsimile or PDF transmission shall constitute effective execution and delivery of this Supplemental
Indenture as to the parties hereto and may be used in lieu of the original Supplemental Indenture and signature pages for all purposes.
The words “execute,” “execution,” “signed,” “signature,” and words of like import
in or related to any document to be signed in connection with the Indenture and the Subordinated Notes shall be deemed to include
electronic signatures (including any electronic signature complying with the U.S. federal ESIGN Act of 2000), each of which shall
be of the same legal effect, validity or enforceability as a manually executed signature. The Company agrees, subject to Section
11.02(b), to assume all risks arising out of the use of using digital signatures and electronic methods to submit communications
to Trustee, including without limitation the risk of Trustee acting on unauthorized instructions, and the risk of interception
and misuse by third parties.


 






    18


     


    

 



 


IN WITNESS WHEREOF, the parties hereto have
caused this Supplemental Indenture to be duly executed, all as of the day and year first above written.


 


	 	BANKUNITED, INC.,

as Company
	 	 
	 	By:	/s/ Leslie Lunak
	 	 	Name:	Leslie Lunak
	 	 	Title:	Chief Financial Officer


 


 


	 	U.S. BANK NATIONAL ASSOCIATION,

as Trustee
	 	 
	 	By:	/s/ Richard Prokosch
	 	 	Name:	Richard Prokosch
	 	 	Title:	Vice President


 


[SIGNATURE PAGE TO SUPPLEMENTAL INDENTURE]


 






    


     


    

  





EXHIBIT A


 


[FORM OF FACE OF SECURITY]


 


THIS SECURITY IS A GLOBAL SECURITY WITHIN
THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITARY OR A NOMINEE OF THE DEPOSITARY,
WHICH SHALL BE TREATED BY THE COMPANY, THE TRUSTEE AND ANY AGENT THEREOF AS OWNER AND HOLDER OF THIS SECURITY FOR ALL PURPOSES.


 


UNLESS THIS CERTIFICATE IS PRESENTED BY
AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, INC. (DTC) TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER,
EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS
WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.


 


TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS
IN WHOLE, BUT NOT IN PART, BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY, OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY
OR ANOTHER NOMINEE OF THE DEPOSITARY, OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR
DEPOSITARY.


 






    A-1


     


    

 


CUSIP No. 06652KAB9


 


BANKUNITED, INC.

5.125% SUBORDINATED NOTES DUE 2030


 


No.       $


As revised by the

Schedule of Increases

or Decreases in

Global Security

attached hereto


 


Interest. BankUnited, Inc. a Delaware
corporation (herein called the “Company”, which term includes any successor Person under the Indenture hereinafter
referred to), for value received, hereby promises to pay to Cede & Co. or registered assigns, the principal sum of dollars
($                   ), as revised
by the Schedule of Increases or Decreases in Global Security attached hereto, on June 11, 2030 and to pay interest thereon from
June 11, 2020 or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually
in arrears on June 11 and December 11 in each year, commencing December 11, 2020 at the rate of 5.125% per annum, until the principal
hereof is paid or made available for payment.


 


Method of Payment. The interest so
payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in such Indenture, be paid to
the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on the Record
Date for such interest, which shall be May 28 and November 27 of each year, preceding the relevant Interest Payment Date. Any such
interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such Record Date and may
either be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice thereof having
been given to Holders of Securities of this series not less than 10 days prior to such Special Record Date, all as more fully provided
in said Indenture. Payment of the principal of (and premium, if any) and any such interest on this Security will be made at the
Corporate Trust Office in U.S. Dollars.


 


Reference is hereby made to the further
provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect
as if set forth at this place.


 


Authentication. Unless the certificate
of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.


 






    A-2


     


    

 


IN WITNESS WHEREOF, the Company has caused
this instrument to be executed by its duly authorized officer.


 


	 	BANKUNITED, INC.
	 	 
	 	By:	 
	 	 	Name:
	 	 	Title:          


 


TRUSTEE’S CERTIFICATE OF AUTHENTICATION


 


Dated:


 


	
        U.S. BANK NATIONAL ASSOCIATION

         

        as Trustee, certifies

        that this is one of

        the Securities referred

        to in the Indenture.

         

	By:	                     	 
	 	Authorized Signatory	 


 









    A-3


     


    

 


[FORM OF REVERSE OF SECURITY]


 


Indenture. This Security is one of
a duly authorized issue of securities of the Company (herein called the “Securities”), issued and to be issued
in one or more series under an Indenture, dated as of June 11, 2020 (the “Base Indenture”), between BankUnited,
Inc. (the “Company”) and U.S. Bank National Association, as trustee (herein called the “Trustee”,
which term includes any successor trustee under the Indenture), as supplemented and amended by the First Supplemental Indenture,
dated June 11, 2020 (the “First Supplemental Indenture,” and the Base Indenture, as so supplemented, herein
called the “Indenture”), between the Company and the Trustee, to which Indenture and all indentures supplemental
thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder
of the Company, the Trustee and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated
and delivered. This Security is one of the series designated on the face hereof, initially limited in aggregate principal amount
to $300,000,000.


 


Optional Redemption. The Company
may redeem the Securities at its option in whole or in part at any time during the three month period prior to the Stated Maturity
at a Redemption Price equal to 100% of the principal amount of the Securities to be redeemed, plus accrued and unpaid interest
to, but excluding, the Redemption Date, subject to obtaining the prior approval of the Board of Governors of the Federal Reserve
System (the “Federal Reserve”) (or any successor bank regulatory agency) to the extent such approval is then
required under the rules of the Federal Reserve (“Federal Reserve Approval”). In addition, the Company may,
at its option, redeem the Securities at any time, in whole but not in part, at a price equal to 100% of the principal amount of
the Securities being redeemed plus interest that is accrued and unpaid to but excluding the date of redemption, subject to Federal
Reserve Approval, upon the occurrence of a Tier 2 Capital Event, a Tax Event or a 1940 Act Event.


 


Other than as specifically set forth above,
the Subordinated Notes may not be redeemed prior to the Stated Maturity. Any redemption of Notes will be subject to the terms of
Article IV of the Base Indenture, as supplemented by the First Supplemental Indenture.


 


Defaults and Remedies. If an Event
of Default (other than a Payment or Covenant Event of Default) with respect to Securities of this series shall occur and be continuing,
the principal of the Securities of this series may be immediately due and payable in the manner and with the effect provided in
the Indenture.


 


Amendment, Modification and Waiver.
The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holders of the Securities of each


 






    A-4


     


    

 


series to be affected under the Indenture at
any time by the Company and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the Securities
at the time Outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of a majority
in aggregate principal amount of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities
of such series, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the
Indenture and their consequences. Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon
such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or
in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Security.


 


Denominations, Transfer and Exchange.
The Securities of this series are issuable only in registered form without coupons in denominations of $2,000 and in integral multiples
of $1,000 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Securities of this
series are exchangeable for a like aggregate principal amount of Securities of like tenor of a different authorized denomination,
as requested by the Holder surrendering the same.


 


As provided in the Indenture and subject
to certain limitations therein set forth, the transfer of this Security is registerable in the Security Register, upon surrender
of this Security for registration of transfer at the Registrar accompanied by a written request for transfer in form satisfactory
to the Company and the Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon
one or more new Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount,
will be issued to the designated transferee or transferees.


 


No service charge shall be made for any
such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental
charge payable in connection therewith.


 


Persons Deemed Owners. Prior to due
presentment of this Security for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee
may treat the Person in whose name this Security is registered as the owner hereof for all purposes, whether or not this Security
be overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.


 


Miscellaneous. The Indenture and
this Security shall be governed by and construed in accordance with the laws of the State of New York.


 


All terms used in this Security and not
defined herein shall have the meanings assigned to them in the Indenture.


 






    A-5


     


    

 





SCHEDULE OF INCREASES OR DECREASES IN GLOBAL
SECURITY


 


The following increases or decreases in
this Global Security have been made:


 


	
        Date of

        Exchange
	 	
        Amount
        of increase in

        Principal Amount of

        this Global Security
	 	
        Amount
        of decrease

        in Principal Amount

        of this Global

        Security
	 	
        Principal
        Amount of

        this Global Security

        following each

        decrease or increase
	 	
        Signature
        of

        authorized signatory

        of Trustee

	 	 	 	 	 	 	 	 	 
	 	 	 	 	 	 	 	 	 
	 	 	 	 	 	 	 	 	 


 









    A-6