Exhibit
10.3


 


INVESTMENT MANAGEMENT
TRUST AGREEMENT


 


This Investment Management Trust Agreement (this
 “Agreement”) is made effective as of [●], 2021, by and between Concord Acquisition Corp III, a Delaware
corporation (the “Company”), and Continental Stock Transfer & Trust Company, a New York limited purpose
trust company (the “Trustee”).


 


WHEREAS, the Company’s registration statement
on Form S-1, File No. 333-254789 (the “Registration Statement”) and prospectus (the “Prospectus”)
for the initial public offering of the Company’s units (the “Units”), each of which consists of one share
of the Company’s Class A common stock, par value $0.0001 per share (the “Common Stock”), and one-half
of one redeemable warrant, each whole warrant entitling the holder thereof to purchase one share of Common Stock (such initial public
offering hereinafter referred to as the “Offering”), has been declared effective as of the date hereof (the
 “Effective Date”) by the U.S. Securities and Exchange Commission (capitalized terms used herein and not otherwise
defined shall have the meanings set forth in the Registration Statement);


 


WHEREAS, the Company has entered into an Underwriting
Agreement (the “Underwriting Agreement”) with Citigroup Global Markets Inc. and Cowen and Company, LLC, as representative
(the “Representatives”) of the several underwriters (the “Underwriters”) named therein;


 


WHEREAS, as described in the Prospectus, and in
accordance with the Company’s amended and restated certificate of incorporation, as the same may be amended from time to time (the
 “Charter”), $255,000,000 of the proceeds of the Offering, the Sponsor Loan (as defined in the Underwriting Agreement)
and the sale of the Private Placement Warrants (as defined in the Underwriting Agreement) (or $293,250,000, if the Underwriters’
over-allotment option is exercised in full) will be delivered to the Trustee to be deposited and held in a segregated trust account located
at all times in the United States (the “Trust Account”) for the benefit of the Company and the holders of the
Common Stock included in the Units issued in the Offering as hereinafter provided (the amount to be delivered to the Trustee (and any
interest subsequently earned thereon) is referred to herein as the “Property,” the stockholders for whose benefit
the Trustee shall hold the Property will be referred to as the “Public Stockholders,” and the Public Stockholders
and the Company will be referred to together as the “Beneficiaries”);


 


WHEREAS, pursuant to the Underwriting Agreement,
a portion of the Property equal to $8,750,000, or $10,062,500 if the Underwriters’ over-allotment option is exercised in full, is
attributable to deferred underwriting discounts and commissions that will be payable by the Company to the Underwriters upon and substantially
concurrently with the consummation of the Business Combination (as defined below) (the “Deferred Discount”);
and


 


WHEREAS, the Company and the Trustee desire to
enter into this Agreement to set forth the terms and conditions pursuant to which the Trustee shall hold the Property.


 


NOW THEREFORE, IT IS AGREED:


 


1.             Agreements
and Covenants of Trustee. The Trustee hereby agrees and covenants to:


 


(a)                
Hold the Property in trust for the Beneficiaries in accordance with the terms of this Agreement in the Trust Account established
by the Trustee in the United States at Morgan Stanley, (or at another U.S.-chartered commercial bank with consolidated assets of $100
billion or more) in the United States, maintained by the Trustee and at a brokerage institution selected by the Trustee that is reasonably
satisfactory to the Company;


 


(b)               
Manage, supervise and administer the Trust Account subject to the terms and conditions set forth herein;


 


(c)                
In a timely manner, upon the written instruction of the Company, invest and reinvest the Property solely in United States government
securities within the meaning of Section 2(a)(16) of the Investment Company Act of 1940, as amended, having a maturity of 185 days
or less, or in money market funds meeting the conditions of paragraphs (d)(1), (d)(2), (d)(3) and (d)(4) of Rule 2a-7 promulgated
under the Investment Company Act of 1940, as amended (or any successor rule), which invest only in direct U.S. government treasury obligations,
as determined by the Company; the trustee may not invest in any other securities or assets, it being understood that the Trust Account
will earn no interest while account funds are uninvested awaiting the Company’s instructions hereunder and the Trustee may earn
bank credits or other consideration during such periods;


 






     


     


    

 


(d)               
Collect and receive, when due, all principal, interest or other income arising from the Property, which shall become part of the
 “Property,” as such term is used herein;


 


(e)                
Promptly notify the Company and the Representatives of all communications received by the Trustee with respect to any Property
requiring action by the Company;


 


(f)                 
Supply any necessary information or documents as may be requested by the Company (or its authorized agents) in connection with
the Company’s preparation of the tax returns relating to assets held in the Trust Account or in connection with the preparation
or completion of the audit of the Company’s financial statements by the Company’s auditors;


 


(g)               
Participate in any plan or proceeding for protecting or enforcing any right or interest arising from the Property if, as and when
instructed by the Company to do so;


 


(h)               
Render to the Company monthly written statements of the activities of, and amounts in, the Trust Account reflecting all receipts
and disbursements of the Trust Account;


 


(i)                 
Commence liquidation of the Trust Account only after and promptly after (x) receipt of, and only in accordance with the terms of,
a letter from the Company (“Termination Letter”) in a form substantially similar to that attached hereto as
either Exhibit A or Exhibit B, as applicable, signed on behalf of the Company by the Chief Executive Officer, Chief Financial Officer,
President, Executive Vice President, Vice President, Secretary or Chairman of the board of directors of the Company (the “Board”)
or other authorized officer of the Company, and, in the case of Exhibit A, acknowledged and agreed to by the Representatives, and complete
the liquidation of the Trust Account and distribute the Property in the Trust Account, including interest  not previously released
to pay the Company’s taxes (which interest shall be net of taxes payable, and less up to $100,000 of interest that may be released
to the Company to pay dissolution expenses), only as directed in the Termination Letter and the other documents referred to therein, or
(y) upon the date which is, the later of (1) 18 months after the closing of the Offering (or up to 24 months after the closing of the
Offering if the Company extends the period of time to consummate the initial business combination, as described in the Prospectus) and
(2) such later date as may be approved by the Company’s stockholders in accordance with the Charter if a Termination Letter has
not been received by the Trustee prior to such date, in which case the Trust Account shall be liquidated in accordance with the procedures
set forth in the Termination Letter attached as Exhibit B and the Property in the Trust Account, including interest not previously released
to pay the Company’s taxes  (which interest shall be net of taxes payable, and less up to $100,000 of interest that may be
released to the Company to pay dissolution expenses) shall be distributed to the Public Stockholders of record as of such date; provided,
however, that the Trustee has no obligation to monitor or question the Company’s position that an allocation has been made for taxes
payable;


 


(j)                 
Upon written request from the Company, which may be given from time to time in a form substantially similar to that attached hereto
as Exhibit C, withdraw from the Trust Account and distribute to the Company the amount of interest earned on the Property requested by
the Company to cover any tax obligation, including any franchise tax obligations, owed by the Company as a result of assets of the Company
or interest or other income earned on the Property, which amount shall be delivered directly to the Company by electronic funds transfer
or other method of prompt payment, and in the case of any tax obligations the Company shall forward such payment to the relevant taxing
authority, as applicable; provided, however, that to the extent there is not sufficient cash in the Trust Account to pay such tax obligation
and/or to fund the Company’s working capital requirements, the Trustee shall liquidate such assets held in the Trust Account as
shall be designated by the Company in writing to make such distribution, so long as there is no reduction in the principal amount per
share initially deposited in the Trust Account; provided, further, that if the tax to be paid is a franchise tax, the written request
by the Company to make such distribution shall be accompanied by a copy of the franchise tax bill from the State of Delaware for the Company
and a written statement from the principal financial officer of the Company setting forth the actual amount payable (it being acknowledged
and agreed that any such amount in excess of interest income earned on the Property shall not be payable from the Trust Account). The
written request of the Company referenced above shall constitute presumptive evidence that the Company is entitled to said funds, and
the Trustee shall have no responsibility to look beyond said request;


 






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(k)               
Upon written request from the Company, which may be given from time to time in a form substantially similar to that attached hereto
as Exhibit D, the Trustee shall distribute to the remitting brokers on behalf of Public Stockholders redeeming shares of Common Stock
the amount required to pay for redeemed shares of Common Stock from Public Stockholders in connection with a stockholder vote to approve
an amendment to the Charter (i) modify the substance or timing of the Company’s obligation to allow redemption in connection with
a Business Combination or to redeem 100% of the shares of Common Stock included in the Units sold in the Offering if the Company does
not complete a Business Combination within the time period set forth in the Company’s Charter or (ii) with respect to any other
provision relating to stockholders’ rights or pre-initial Business Combination activity. The written request of the Company referenced
above shall constitute presumptive evidence that the Company is entitled to distribute said funds, and the Trustee shall have no responsibility
to look beyond said request; and


 


(l)                 
Not make any withdrawals or distributions from the Trust Account other than pursuant to Sections 1(i), 1(j) or 1(k) above.


 


2.             Agreements
and Covenants of the Company. The Company hereby agrees and covenants to:


 


(a)                
Give all instructions to the Trustee hereunder in writing, signed by the Company’s Chairman of the Board, Chief Executive
Officer, Chief Financial Officer, President, Executive Vice President, Vice President or Secretary. In addition, except with respect to
its duties under Sections 1(i), 1(j) and 1(k) hereof, the Trustee shall be entitled to rely on, and shall be protected in relying
on, any verbal or telephonic advice or instruction which it, in good faith and with reasonable care, believes to be given by any one of
the persons authorized above to give written instructions, provided that the Company shall promptly confirm such instructions in writing;


 


(b)               
Subject to Section 4 hereof, hold the Trustee harmless and indemnify the Trustee from and against any and all expenses, including
reasonable counsel fees and disbursements, or losses suffered by the Trustee in connection with any action taken by it hereunder and in
connection with any action, suit or other proceeding brought against the Trustee involving any claim, or in connection with any claim
or demand, which in any way arises out of or relates to this Agreement, the services of the Trustee hereunder, or the Property or any
interest earned on the Property, except for expenses and losses resulting from the Trustee’s gross negligence, fraud or willful
misconduct. Promptly after the receipt by the Trustee of notice of demand or claim or the commencement of any action, suit or proceeding,
pursuant to which the Trustee intends to seek indemnification under this Section 2(b), it shall notify the Company in writing of
such claim (hereinafter referred to as the “Indemnified Claim”). The Trustee shall have the right to conduct
and manage the defense against such Indemnified Claim; provided that the Trustee shall obtain the consent of the Company with respect
to the selection of counsel, which consent shall not be unreasonably withheld. The Trustee may not agree to settle any Indemnified Claim
without the prior written consent of the Company, which such consent shall not be unreasonably withheld. The Company may participate in
such action with its own counsel;


 


(c)                
Pay the Trustee the fees set forth on Schedule A hereto, including an initial acceptance fee, annual administration fee, and transaction
processing fee which fees shall be subject to modification by the parties from time to time. It is expressly understood that the Property
shall not be used to pay such fees unless the disbursements are made to the Company pursuant to Section 1(i) solely in connection with
the completion of a Business Combination (defined below). The Company shall pay the Trustee the initial acceptance fee and the first annual
administration fee at the consummation of the Offering and thereafter on the anniversary of the Effective Date. The Trustee shall refund
the Company the annual administration fee (on a pro rata basis) with respect to any period after the liquidation of the Trust Account.
The Company shall not be responsible for any other fees or charges of the Trustee except as set forth in this Section 2(c), Schedule A
and as may be provided in Section 2(b) hereof;


 


(d)               
In connection with any vote of the Company’s stockholders regarding a merger, capital stock exchange, asset acquisition,
stock purchase, reorganization or similar business combination involving the Company and one or more businesses (the “Business
Combination”), provide to the Trustee an affidavit or certificate of the inspector of elections for the stockholder meeting
(which inspector of elections may be the Trustee) verifying the vote of such stockholders regarding such Business Combination;


 






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(e)                
Provide the Representatives with a copy of any Termination Letter(s) and/or any other correspondence that is sent to the Trustee
with respect to any proposed withdrawal from the Trust Account promptly after it issues the same;


 


(f)                 
Instruct the Trustee to make only those distributions that are permitted under this Agreement, and refrain from instructing the
Trustee to make any distributions that are not permitted under this Agreement; and


 


(g)               
Expressly provide in any Instruction Letter (as defined in Exhibit A) delivered in connection with a Termination Letter in the
form of Exhibit A that the Deferred Discount be paid directly to the account or accounts directed by the Representatives on behalf of
the Underwriters prior to any transfer of the funds held in the Trust Account to the Company or any other person; and


 


(h)               
Within four (4) business days after the Representatives exercise the over-allotment option (or any unexercised portion thereof)
or such over-allotment expires, provide the Trustee with a notice in writing (with copies to the Underwriters) of the total amount of
the Deferred Discount, which shall in no event be less than $8,750,000, or $10,062,500 if the Underwriters’ overallotment option
is exercised in full.


 


3.        
      Limitations of Liability. The Trustee shall have no responsibility or liability to:


 


(a)                
Imply obligations, perform duties, inquire or otherwise be subject to the provisions of any agreement or document other than this
Agreement and that which is expressly set forth herein;


 


(b)               
Take any action with respect to the Property, other than as directed in Section 1 hereof, and the Trustee shall have no liability
to any third party except for liability arising out of the Trustee’s gross negligence, fraud or willful misconduct;


 


(c)                
Institute any proceeding for the collection of any principal and income arising from, or institute, appear in or defend any proceeding
of any kind with respect to, any of the Property unless and until it shall have received instructions from the Company given as provided
herein to do so and the Company shall have advanced or guaranteed to it funds sufficient to pay any expenses incident thereto;


 


(d)               
Refund any depreciation in principal of any Property;


 


(e)                
Assume that the authority of any person designated by the Company to give instructions hereunder shall not be continuing unless
provided otherwise in such designation, or unless the Company shall have delivered a written revocation of such authority to the Trustee;


 


(f)                 
The other parties hereto or to anyone else for any action taken or omitted by it, or any action suffered by it to be taken or omitted,
in good faith and in the Trustee’s best judgment, except for the Trustee’s gross negligence, fraud or willful misconduct.
The Trustee may rely conclusively and shall be protected in acting upon any order, notice, demand, certificate, opinion or advice of counsel
(including counsel chosen by the Trustee, which counsel may be the Company’s counsel), statement, instrument, report or other paper
or document (not only as to its due execution and the validity and effectiveness of its provisions, but also as to the truth and acceptability
of any information therein contained) which the Trustee believes, in good faith and with reasonable care, to be genuine and to be signed
or presented by the proper person or persons. The Trustee shall not be bound by any notice or demand, or any waiver, modification, termination
or rescission of this Agreement or any of the terms hereof, unless evidenced by a written instrument delivered to the Trustee, signed
by the proper party or parties and, if the duties or rights of the Trustee are affected, unless it shall give its prior written consent
thereto;


 


(g)               
Verify the accuracy of the information contained in the Registration Statement;


 


(h)               
Provide any assurance that any Business Combination entered into by the Company or any other action taken by the Company is as
contemplated by the Registration Statement;


 






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(i)                 
File information returns with respect to the Trust Account with any local, state or federal taxing authority or provide periodic
written statements to the Company documenting the taxes payable by the Company, if any, relating to any interest income earned on the
Property;


 


(j)                 
Prepare, execute and file tax reports, income or other tax returns and pay any taxes with respect to any income generated by, and
activities relating to, the Trust Account, regardless of whether such tax is payable by the Trust Account or the Company, including, but
not limited to, franchise and income tax obligations, except pursuant to Section 1(j) hereof; or


 


(k)               
Verify calculations, qualify or otherwise approve the Company’s written requests for distributions pursuant to Sections 1(i),
1(j) or 1(k) hereof.


 


4.             Trust
Account Waiver. The Trustee has no right of set-off or any right, title, interest or claim of any kind (“Claim”)
to, or to any monies in, the Trust Account, and hereby irrevocably waives any Claim to, or to any monies in, the Trust Account that it
may have now or in the future. In the event the Trustee has any Claim against the Company under this Agreement, including, without limitation,
under Section 2(b) or Section 2(c) hereof, the Trustee shall pursue such Claim solely against the Company and its assets outside
the Trust Account and not against the Property or any monies in the Trust Account.


 


5.             Termination.
This Agreement shall terminate as follows:


 


(a)                
If the Trustee gives written notice to the Company that it desires to resign under this Agreement, the Company shall use its reasonable
efforts to locate a successor trustee, pending which the Trustee shall continue to act in accordance with this Agreement. At such time
that the Company notifies the Trustee that a successor trustee has been appointed by the Company and has agreed to become subject to the
terms of this Agreement, the Trustee shall transfer the management of the Trust Account to the successor trustee, including but not limited
to the transfer of copies of the reports and statements relating to the Trust Account, whereupon this Agreement shall terminate; provided,
however, that in the event that the Company does not locate a successor trustee within ninety (90) days of receipt of the resignation
notice from the Trustee, the Trustee may submit an application to have the Property deposited with any court in the State of New York
or with the United States District Court for the Southern District of New York and upon such deposit, the Trustee shall be immune from
any liability whatsoever;


 


(b)               
At such time that the Trustee has completed the liquidation of the Trust Account and its obligations in accordance with the provisions
of Section 1(i) hereof (which section may not be amended under any circumstances) and distributed the Property in accordance with
the provisions of the Termination Letter, this Agreement shall terminate except with respect to Section 2(b) and Section 4;
or


 


(c)                
If the Offering is not consummated within ten (10) business days of the date of this Agreement, in which case any funds received
by the Trustee from the Company, CA2 Co-Investment LLC or Concord Sponsor Group III LLC, as applicable, shall be returned promptly following
the receipt by the Trustee of written instructions from the Company.


 


6.             Miscellaneous.


 


(a)                
The Company and the Trustee each acknowledge that the Trustee will follow the security procedures set forth below with respect
to funds transferred from the Trust Account. The Company and the Trustee will each restrict access to confidential information relating
to such security procedures to authorized persons. Each party must notify the other party immediately if it has reason to believe unauthorized
persons may have obtained access to such confidential information, or of any change in its authorized personnel. In executing funds transfers,
the Trustee shall rely upon all information supplied to it by the Company, including, account names, account numbers, and all other identifying
information relating to a Beneficiary, Beneficiary’s bank or intermediary bank. Except for any liability arising out of the Trustee’s
gross negligence, fraud or willful misconduct, the Trustee shall not be liable for any loss, liability or expense resulting from any error
in the information or transmission of the funds.


 






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(b)               
This Agreement shall be governed by and construed and enforced in accordance with the laws of the State of New York, without giving
effect to conflicts of law principles that would result in the application of the substantive laws of another jurisdiction. This Agreement
may be executed in several original or facsimile counterparts, each one of which shall constitute an original, and together shall constitute
but one instrument.


 


(c)                
This Agreement contains the entire agreement and understanding of the parties hereto with respect to the subject matter hereof.
This Agreement or any provision hereof may only be changed, amended or modified (other than to correct a typographical error) by a writing
signed by each of the parties hereto.


 


(d)               
This Agreement or any provision hereof may only be changed, amended or modified pursuant to Section 6(c) hereof with the Consent
of the Stockholders. For purposes of this Section 6(d), the “Consent of the Stockholders” means (i) receipt
by the Trustee of a certificate from the inspector of elections of the stockholder meeting certifying that the Company’s stockholders
of record as of a record date established in accordance with Section 213(a) of the Delaware General Corporation Law, as amended (or any
successor rule), who hold sixty-five percent (65%) or more of all then outstanding shares of the Common Stock and Class B common stock,
par value $0.0001 per share, of the Company voting together as a single class, have voted in favor of such change, amendment or modification,
or (ii) the Company’s stockholders of record as of the record date who hold sixty-five percent (65%) or more of all then outstanding
shares of the Common Stock and Class B common stock, par value $0.0001 per share, of the Company voting together as a single class, have
delivered to the Trustee a signed writing approving such change, amendment or modification. No such amendment will affect any Public Stockholder
who has otherwise indicated his, her or its election to redeem his, her or its shares of Common Stock in connection with a stockholder
vote sought to amend this Agreement, including a corresponding change to the Charter. Except for any liability arising out of the Trustee’s
gross negligence, fraud or willful misconduct, the Trustee may rely conclusively on the certification from the inspector or elections
referenced above and shall be relieved of all liability to any party for executing the proposed amendment in reliance thereon.


 


(e)                
The parties hereto consent to the jurisdiction and venue of any state or federal court located in the City of New York, State of
New York, for purposes of resolving any disputes hereunder. AS TO ANY CLAIM, CROSS-CLAIM OR COUNTERCLAIM IN ANY WAY RELATING TO THIS AGREEMENT,
EACH PARTY WAIVES THE RIGHT TO TRIAL BY JURY.


 


(f)                 
Any notice, consent or request to be given in connection with any of the terms or provisions of this Agreement shall be in writing
and shall be sent by express mail or similar private courier service, by certified mail (return receipt requested), by hand delivery or
by electronic mail:


 


if to the Trustee, to:


 


Continental Stock Transfer & Trust Company

1 State Street, 30th Floor

New York, NY 10004

Attn:  Francis Wolf and Celeste Gonzalez

Email: fwolf@continentalstock.com 


Email: cgonzalez@continentalstock.com


 


if to the Company, to:


 


Concord Acquisition Corp III


477 Madison Avenue


New York, NY 10022

Attn: Jeff Tuder

Email:jeff@tremsoncapital.com


 






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in each case, with copies
to:


 


Greenberg Traurig, LLP


1750 Tysons Boulevard, Suite 1000


McLean, VA 22102

Attn: Alan I. Annex, Esq. and Jason T. Simon, Esq.

Email:annexa@gtlaw.com and simonj@gtlaw.com


 


and:


 


DLA Piper LLP (US)

1251 Avenue of the Americas

New York, NY 10020

Attn: Michael D. Maline, Esq. and Stephen P. Alicanti, Esq.

Email:michael.maline@dlapiper.com and stephen.alicanti@dlapiper.com


 


(g)               
Each of the Company and the Trustee hereby represents that it has the full right and power and has been duly authorized to enter
into this Agreement and to perform its respective obligations as contemplated hereunder. The Trustee acknowledges and agrees that it shall
not make any claims or proceed against the Trust Account, including by way of set-off, and shall not be entitled to any funds in the Trust
Account under any circumstance.


 


(h)               
This Agreement is the joint product of the Trustee and the Company and each provision hereof has been subject to the mutual consultation,
negotiation and agreement of such parties and shall not be construed for or against any party hereto.


 


(i)                 
This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts
shall together constitute one and the same instrument. Delivery of a signed counterpart of this Agreement by facsimile or electronic transmission
shall constitute valid and sufficient delivery thereof.


 


(j)                 
Each of the Company and the Trustee hereby acknowledges and agrees that the Representatives on behalf of the Underwriters is a
third party beneficiary of this Agreement.


 


(k)               
Except as specified herein, no party to this Agreement may assign its rights or delegate its obligations hereunder to any other
person or entity.


 


[Signature Page Follows]


 



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IN WITNESS WHEREOF, the parties have duly
executed this Investment Management Trust Agreement as of the date first written above.


 


	 	CONTINENTAL STOCK TRANSFER &
	 	TRUST COMPANY, as Trustee
	 	 
	 	By:	      
	 	Name:
	 	Title:
	 	 
	 	CONCORD Acquisition Corp III
	 	 
	 	By:	 
	 	Name:
	 	Title:



 


[Signature Page to Investment Management Trust Agreement]



     


     


    




SCHEDULE A


 


	Fee Item	 	Time and method of payment	 	Amount	 
	Initial set-up fee	 	Initial closing of Offering by wire transfer	 	$	3,500.00	 
	Trustee administration fee	 	First year, initial closing of Offering by wire transfer, thereafter on the anniversary of the effective date of the Offering by wire transfer or check	 	$	10,000.00	 
	Transaction processing fee for disbursements to Company under Sections 1(i), 1(j) and 1(k)	 	Billed to Company following disbursement made to Company under Sections 1(i), 1(j) and 1(k)	 	$	250.00	 
	Paying Agent services as required pursuant to Sections 1(i) and 1(k)	 	Billed to Company upon delivery of service pursuant to Sections 1(i) and 1(k)	 	 	Prevailing rates	 



 



     


     


    




 


EXHIBIT A


 


[Letterhead of Company]


 


[Insert date]


 


Continental Stock Transfer & Trust Company

1 State Street, 30th Floor

New York, New York 10004

Attn: Francis Wolf and Celeste Gonzalez


 


Re:Trust Account - Termination Letter


 


Dear Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(i) of the Investment
Management Trust Agreement between Concord Acquisition Corp III (the “Company”) and Continental Stock Transfer
 & Trust Company (the “Trustee”), dated as of _________, 2021 (the “Trust Agreement”),
this is to advise you that the Company has entered into an agreement with [__________] (the “Target Business”)
to consummate a business combination with the Target Business (the “Business Combination”) on or about [insert
date]. The Company shall notify you at least seventy-two (72) hours in advance (or such shorter time as you may agree) of the actual date
of the consummation of the Business Combination (the “Consummation Date”). Capitalized terms used but not defined
herein shall have the meanings set forth in the Trust Agreement.


 


In accordance with the terms of the Trust Agreement,
we hereby authorize you to commence to liquidate all of the assets of the Trust Account and to transfer the proceeds to a segregated account
held by you on behalf of the Beneficiaries to the effect that, on the Consummation Date, all of the funds held in the Trust Account will
be immediately available for transfer to the account or accounts that the Company shall direct on the Consummation Date (including as
directed to it by the Representatives on behalf of the Underwriters (with respect to the Deferred Discount)). It is acknowledged and agreed
that while the funds are on deposit in the trust operating account at Morgan Stanley awaiting distribution, neither the Company nor the
Representatives will earn any interest or dividends.


 


On the Consummation Date (i) counsel for the Company
shall deliver to you written notification that the Business Combination has been consummated, or will be consummated substantially concurrently
with your transfer of funds to the accounts as directed by the Company (the “Notification”) and (ii) the Company
shall deliver to you (a) a certificate of the Chief Executive Officer, which verifies that the Business Combination has been approved
by a vote of the Company’s stockholders, if a vote is held and (b) a joint written instruction signed by the Company and the Representatives
with respect to the transfer of the funds held in the Trust Account, including payment of the Deferred Discount from the Trust Account
(the “Instruction Letter”). You are hereby directed and authorized to transfer the funds held in the Trust Account
immediately upon your receipt of the Notification and the Instruction Letter, in accordance with the terms of the Instruction Letter.
In the event that certain deposits held in the Trust Account may not be liquidated by the Consummation Date without penalty, you will
notify the Company in writing of the same and the Company shall direct you as to whether such funds should remain in the Trust Account
and be distributed after the Consummation Date to the Company. Upon the distribution of all the funds, net of any payments necessary for
reasonable unreimbursed expenses related to liquidating the Trust Account, your obligations under the Trust Agreement shall be terminated.


 



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In the event that the Business Combination is not
consummated on the Consummation Date described in the notice thereof and we have not notified you on or before the original Consummation
Date of a new Consummation Date, then upon receipt by the Trustee of written instructions from the Company, the funds held in the Trust
Account shall be reinvested as provided in Section 1(c) of the Trust Agreement on the business day immediately following the Consummation
Date as set forth in such notice as soon thereafter as possible.


 


	 	Very truly yours,
	 	 
	 	Concord Acquisition Corp III
	 	 
	 	By:	    
	 	Name:
	 	Title:



 


	Acknowledged and Agreed:	 
	 	 
	Cowen and Company, LLC	 
	 	 
	By:	      	 
	Name:	 
	Title:	 



 



    A-2


     


    




 


EXHIBIT B


 


[Letterhead of Company]


 


[Insert date]


 


Continental Stock Transfer & Trust Company

1 State Street, 30th Floor

New York, New York 10004

Attn: Francis Wolf and Celeste Gonzalez


 


Re:Trust Account - Termination Letter


 


Dear Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(i) of the Investment
Management Trust Agreement between Concord Acquisition Corp III (the “Company”) and Continental Stock Transfer
 & Trust Company (the “Trustee”), dated as of _________, 2021 (the “Trust Agreement”),
this is to advise you that the Company did not effect a business combination with a Target Business (the “Business Combination”)
within the time frame specified in the Company’s Charter, as described in the Company’s Prospectus relating to the Offering.
Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


In accordance with the terms of the Trust Agreement,
we hereby authorize you to liquidate all of the assets in the Trust Account and transfer the total proceeds into a segregated account
held by you on behalf of the Beneficiaries to await distribution to the Public Stockholders. The Company has selected _________, 20__1
as the effective date for the purpose of determining when the Public Stockholders will be entitled to receive their share of the liquidation
proceeds. You agree to be the Paying Agent of record and, in your separate capacity as Paying Agent, agree to distribute said funds directly
to the Company’s Public Stockholders in accordance with the terms of the Trust Agreement and the Company’s Charter. Upon the
distribution of all the funds, net of any payments necessary for reasonable unreimbursed expenses related to liquidating the Trust Account,
your obligations under the Trust Agreement shall be terminated, except to the extent otherwise provided in Section 1(i) of
the Trust Agreement.


 


	 	Very truly yours,
	 	 
	 	Concord Acquisition Corp III
	 	 
	 	By:	    
	 	Name:
	 	Title:



 


	cc:	Cowen and Company, LLC	 
	 	Citigroup Global Markets Inc.	 



 


 






1 18 months from the closing of the Offering or at a later date, if extended.



    B-1


     


    




 


EXHIBIT C


 


[Letterhead of Company]


 


[Insert date]


 


Continental Stock Transfer & Trust Company

1 State Street, 30th Floor

New York, New York 10004

Attn: Francis Wolf and Celeste Gonzalez


 


Re:Trust Account - Withdrawal Instruction


 


Dear Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(j) of the Investment
Management Trust Agreement between Concord Acquisition Corp III (the “Company”) and Continental Stock Transfer
 & Trust Company (the “Trustee”), dated as of _________, 2021 (the “Trust Agreement”),
the Company hereby requests that you deliver to the Company $[_____] of the interest income earned on the Property as of the date hereof.
Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


The Company needs such funds to pay for the tax
obligations as set forth on the attached tax return or tax statement. In accordance with the terms of the Trust Agreement, you are hereby
directed and authorized to transfer (via wire transfer) such funds promptly upon your receipt of this letter to the Company’s operating
account at:


 


[WIRE INSTRUCTION
INFORMATION]


 


	 	Very truly yours,
	 	 
	 	Concord Acquisition Corp III
	 	 
	 	By:	    
	 	Name:
	 	Title:



 


	cc:	Cowen and Company, LLC	 
	 	Citigroup Global Markets Inc.	 



 






    C-1


     


    

 


EXHIBIT D


 


[Letterhead of Company]


 


[Insert date]


 


Continental Stock Transfer & Trust Company

1 State Street, 30th Floor

New York, New York 10004

Attn: Francis Wolf and Celeste Gonzalez


 


Re:Trust Account - Stockholder Redemption Withdrawal
Instruction


 


Dear Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(k) of the Investment
Management Trust Agreement between Concord Acquisition Corp III (the “Company”) and Continental Stock Transfer
 & Trust Company (the “Trustee”), dated as of _________, 2021 (the “Trust Agreement”),
the Company hereby requests that you deliver to the redeeming Public Stockholders of the Company $[_____] of the principal and interest
income earned on the Property as of the date hereof to a segregated account held by you on behalf of the Beneficiaries for distribution
to the Public Stockholders who have requested redemption of their shares of Common Stock. Capitalized terms used but not defined herein
shall have the meanings set forth in the Trust Agreement.


 


The Company needs such funds to pay its Public
Stockholders who have properly elected to have their shares of Common Stock redeemed by the Company in connection with a stockholder vote
to approve an amendment to the Company’s Charter to (i) modify the substance or timing of the Company’s obligation to allow
redemption in connection with a Business Combination or to redeem 100% of the shares of Common Stock included in the Units sold in the
Offering if the Company does not complete a Business Combination within the time period set forth in the Company’s Charter or (ii)
with respect to any other provision relating to stockholders’ rights or pre-initial Business Combination activity. As such, you
are hereby directed and authorized to transfer (via wire transfer) such funds promptly upon your receipt of this letter.


 


	 	Very truly yours,
	 	 
	 	Concord Acquisition Corp III
	 	 
	 	By:	    
	 	Name:
	 	Title:



 


	cc:	Cowen and Company, LLC	 
	 	Citigroup Global Markets Inc.	 



 



    D-1