Exhibit 10.2


 


FORM
OF INVESTMENT MANAGEMENT TRUST AGREEMENT


 


This Investment Management Trust Agreement (this
 “Agreement”) is made effective as of [•], 2021, by and between Seaport Calibre Materials Acquisition Corp.,
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-[•] ( 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 by the
U.S. Securities and Exchange Commission;


 


WHEREAS, the Company has entered into an Underwriting
Agreement (the “Underwriting Agreement”) with Seaport Global Securities, LLC as representative (the “Representative”)
of the several underwriters (the “Underwriters”) named therein;


 


WHEREAS, as described in the Prospectus, $151,500,000
of the proceeds of the Offering and sale of the Private Placement Warrants (as defined in the Underwriting Agreement) (or $174,225,000,
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 Business Combination Marketing
Agreement, a portion of the Property equal to $5,250,000, or $6,037,500 if the Underwriters’ over-allotment option is exercised
in full, will be payable by the Company to the Underwriters upon and concurrently with the consummation of the Business Combination (as
defined below) (the “Marketing Fee”); 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 J.P. Morgan Chase
Bank, N.A. (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; it being understood that
the Trust Account will earn no interest while account funds are uninvested awaiting the Company’s instructions hereunder; while
account funds are invested or uninvested the Trustee may earn bank credits or other consideration;


 






     


     


    

 


(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 Representative
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;


 


(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 and the Representative, if
applicable (“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 its 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 complete the liquidation of the Trust Account and distribute the Property in the Trust
Account, including interest earned on the funds held in the Trust Account and not previously released to the Company to pay its franchise
and income taxes (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 and (2) such later date as may be approved by the Company’s stockholders in accordance with the Company’s
amended and restated certificate of incorporation 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 earned on the funds held in the Trust Account and not previously released
to the Company to pay its franchise and income taxes (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;


 


(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 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, 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 (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;


 


(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 on behalf of the Company the amount requested by the Company to be used to redeem shares of Common Stock from Public
Stockholders properly submitted in connection with a stockholder vote to approve an amendment to the Company’s amended and
restated certificate of incorporation 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 amended and restated
certificate of incorporation or (ii) with respect to any other provision relating to stockholders’ rights or pre-initial
Business Combination activity; and


 


(l) Not make any withdrawals or distributions from
the Trust Account other than pursuant to Section 1(i), (j) or (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
and until the closing of the 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. 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 verifying the vote of such stockholders regarding such Business
Combination;


 


(e) Provide the Representative 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) Unless otherwise agreed among the Company and
the Representative, ensure that any Instruction Letter (as defined in Exhibit A) delivered in connection with a Termination Letter in
the form of Exhibit A expressly provides that the Marketing Fee is paid directly to the account or accounts directed by the Representative
on behalf of the Underwriters prior to any transfer of the funds held in the Trust Account to the Company or any other person;


 






     


     


    

 


(g) 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


 


(h) Within five (5) business days after the Representative,
on behalf of the Underwriters, exercises the over-allotment option (or any unexercised portion thereof) or such over-allotment option
expires, provide the Trustee with a notice in writing of the total amount of the Marketing Fee, which shall in no event be less than $5,250,000.


 


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;


 


(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; or


 


(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.


 


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.


 


(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
fifty percent (50%) 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 fifty percent (50%) 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 Company’s amended and restated
certificate of incorporation. 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

cgonzalez@continentalstock.com


 


if to the Company, to:


 


Seaport Calibre Materials Acquisition Corp.

360 Madison Avenue, 20th Floor

New York, NY 10017

Attn: Jim Tumulty, Chief Executive Officer

Email: jtumulty@calibregroupllc.com


 


in each case, with copies,
which shall not constitute notice, to:


 


Paul Hastings LLP


200 Park Avenue

New York, NY 10166

Attn: Frank Lopez and Will Burns

Email: franklopez@paulhastings.com, willburns@paulhastings.com


 


and


 


Seaport Global Securities, LLC


360 Madison Avenue


New York, NY 10017


Attn: Jack Mascone
and Brian Devaney


Email: jmascone@seaportglobal.com,
bdevaney@seaportglobal.com


 


and


Baker Botts L.L.P


910 Louisiana Street


Houston, TX 77002


Attn: Douglas V. Getten and Travis J.
Wofford


Email: doug.getten@bakerbotts.com, travis.wofford@bakerbotts.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 Representative 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]


 






     


     


    

 


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:	Francis Wolf
	 	Title:	Vice President 
	 	 	 
	 	SEAPORT CALIBRE MATERIALS ACQUISITION CORP.
	 	 
	 	By:	 
	 	Name:	Jim Tumulty
	 	Title:	Chief Executive Officer


 


[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 fee payable at 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) and 1(j)	 	Billed to Company following disbursement made to Company under Section 1	 	$	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


 


Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(i) of the Investment Management
Trust Agreement between Seaport Calibre Materials Acquisition Corp. (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 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 Operating
Account at JP Morgan Chase Bank, N.A. 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 Representative on behalf of the Underwriters (with respect to the Marketing
Fee)). It is acknowledged and agreed that while the funds are on deposit in the trust operating account at J.P. Morgan Chase Bank, N.A.
awaiting distribution, the Company will not 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 Representative
with respect to the transfer of the funds held in the Trust Account, including payment of amounts owed to public stockholders who have
properly exercised their redemption rights and payment of the Marketing Fee to the Representative 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.


 


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,
	 	 
	 	Seaport Calibre Materials Acquisition Corp.  
	 	 
	 	By:	 
	 	Name:	Jim Tumulty
	 	Title:	Chief Executive Officer
	 	 	 
	 	Seaport Global Securities, LLC
	 	 	 
	 	By:	 
	 	Name:	 
	 	Title:



 






    


     


    

 


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


 


Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(i) of the Investment Management
Trust Agreement between Seaport Calibre Materials Acquisition Corp. (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 amended and restated certificate of incorporation, 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 amended and restated
certificate of incorporation. 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,
	 	 	 
	 	 	Seaport Calibre Materials Acquisition Corp.
	 	 	 
	 	 	By:	 
	 	 	Name:	Jim Tumulty
	 	 	Title:	Chief Executive Officer
	 	 	 	 
	cc:	Seaport Global Securities, LLC	 


 





 






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


 






    


     


    

 


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


 


Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(j) of the Investment Management
Trust Agreement between Seaport Calibre Materials Acquisition Corp. (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,
	 	 	 
	 	 	Seaport Calibre Materials Acquisition Corp.
	 	 	 
	 	 	By:	 
	 	 	Name:	Jim Tumulty
	 	 	Title:	Chief Executive Officer
	 	 	 	 
	cc:	Seaport Global Securities, LLC	 


 






    


     


    

 


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


 


Mr. Wolf and Ms. Gonzalez:


 


Pursuant to Section 1(k) of the Investment Management
Trust Agreement between Seaport Calibre Materials Acquisition Corp. (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 amended and restated certificate of incorporation 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 amended and restated certificate of incorporation 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,
	 	 	 
	 	 	Seaport Calibre Materials Acquisition Corp.
	 	 	 
	 	 	By:	 
	 	 	Name:	Jim Tumulty
	 	 	Title:	Chief Executive Officer
	 	 	 	 
	cc:	Seaport Global Securities, LLC