EX-10.3





 Exhibit 10.3 

INVESTMENT MANAGEMENT TRUST AGREEMENT 

This Investment Management Trust Agreement (this “Agreement”) is made effective as of
                , 2021, by and between Post Holdings Partnering Corporation, a Delaware Corporation (the “Company”), and Continental Stock
Transfer & Trust Company, a New York corporation (the “Trustee”). 
 WHEREAS, the Company’s
registration statement on Form S-1, File No. 333-252910 (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 of the Company’s Series A common stock, par value $0.0001 per share (the
“Common Stock”), and one-third 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 United States Securities and Exchange Commission; and 

WHEREAS, the Company has entered into an Underwriting Agreement (the “Underwriting Agreement”) with Evercore
Group L.L.C. and Barclays Capital Inc., as representatives (the “Representatives”) of the several underwriters (the “Underwriters”) named therein; and 

WHEREAS, as described in the Prospectus, $300,000,000 of the gross proceeds of the Offering and sale of the Private Placement Units (as
defined in the Underwriting Agreement) (or $345,000,000 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 shares of 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”); and 

WHEREAS, pursuant to the Underwriting Agreement, a portion of the Property equal to $[●], or $[●] if the Underwriters’
over-allotment option is exercised in full, is attributable to deferred underwriting discounts and commissions that may be payable by the Company to the Underwriters upon the consummation of the Partnering Transaction (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 located in the United States at J.P. Morgan Chase Bank, N.A. (or at another United States chartered commercial bank with consolidated assets of $100 billion or more) 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 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, which invest only in direct United States 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 on deposit, the Trustee may earn bank credits or other consideration; 

(d) Collect and receive, when due, all 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 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 signed on behalf of the Company by its President, Principal Financial Officer, Principal Accounting Officer, Chief Corporate Development Officer, Chief Legal Officer or Secretary of the Company 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 (which interest shall be net of taxes payable, and less up to $100,000 of interest may be
released to the Company to pay dissolution expenses, it being understood that the Trustee has no obligation to monitor or question the Company’s position that an allocation has been made for taxes payable), only as directed in the Termination
Letter and the other documents referred to therein; provided, that, in the case a 

  
 2 













 
Termination Letter in the form of Exhibit A is received, or (y) upon the date which is twenty-four (24) months after the closing of the Offering (or twenty- seven (27) months from
the closing of the Offering if the Company has executed a letter of intent, agreement in principle or definitive agreement for a Partnering Transaction within twenty-four (24) months from the closing of the Offering but has not completed a
Partnering Transaction within such twenty-four (24) month period), or such later date as may be approved by the Company’s stockholders in accordance with the Company’s amended and restated certificate of incorporation, as it may be
amended from time to time, 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 (which interest shall be net of taxes payable, and less up to $100,000 of interest 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 (a “Tax Payment Withdrawal Instruction”), 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 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; 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, however, 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 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 (a “Stockholder Redemption Withdrawal Instruction”), 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 (A) to
modify the substance or timing of the Company’s obligation to allow redemption in connection with the Company’s initial merger, share exchange, asset acquisition, share purchase, reorganization or similar partnering transaction involving
the Company and one or more businesses (a “Partnering Transaction”) or to redeem 100% of the Company’s public shares if it does not complete its Partnering Transaction within twenty-four (24) months from the closing
of the Offering (or twenty-seven (27) months from the closing of the Offering if the Company has executed a letter of intent, agreement in principle or definitive agreement for a Partnering Transaction within twenty-four (24) months from
the closing of the Offering but has not completed a Partnering Transaction within such twenty-four (24) month period) or (B) with respect to any other provision relating to stockholders’ rights or
pre-Partnering Transaction 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 

  
 3 













 (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 President, Principal Financial Officer,
Principal Accounting Officer, Chief Corporate Development Officer, Chief Legal Officer, Secretary or other authorized officer of the Company. 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 reasonable and documented expenses, including reasonable outside 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 it is distributed to the Company pursuant to Sections 1(i) through 1(j) hereof. 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) and as may be provided in Section 2(b) hereof; 

(d) In connection with any vote of the Company’s stockholders regarding a Partnering Transaction, 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 Partnering Transaction; 

  
 4 













 (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) 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; and 
 (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. 

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 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 with written notification to the Company, 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; 

  
 5 













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

(h) Provide any assurance that any Partnering Transaction 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 and has agreed to become subject
to the terms of this Agreement (whether following the Trustee giving notice that it desires to resign under this Agreement or the Company otherwise electing to replace the Trustee under 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; 

  
 6 













 (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 and distributed the Property in accordance with the provisions of the Termination Letter, this Agreement shall terminate except with respect to Section 2(b); 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 or PHPC Sponsor, LLC for purposes of funding the Trust Account shall be promptly returned to the Company or PHPC Sponsor, LLC, as applicable. 

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 out-of-pocket 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. 

(c) This Agreement contains the entire agreement and understanding of the parties hereto with respect to the subject matter hereof. Except for
Section 1(i), 1(j) and 1(k) hereof (which sections may not be modified, amended or deleted without the affirmative vote of sixty-six and 2/3rds percent (662⁄3%) of the then outstanding shares of Common Stock, Series B shares of common stock of the Company, par value $0.0001 per share, and Series F shares of common stock of
the Company, par value $0.0001 per share, voting together as a single class; provided that 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), 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) 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. 

  
 7 













 (e) 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, by electronic mail: 

if to the Trustee, to: 

Continental Stock Transfer & Trust Company 

One State Street, 30th Floor 

New York, New York 10004 
 Attn:
Francis Wolf and Celeste Gonzalez 
 E-mail: fwolf@continentalstock.com 

E-mail: cgonzalez@continentalstock.com 

if to the Company, to: 
 Post
Holdings Partnering Corporation 
 2503 S. Hanley Road 

St. Louis, Missouri 63144 

Attn: Brad Harper 
 Email:
brad.harper@postholdings.com 
 in each case, with copies to: 

Kirkland & Ellis LLP 

300 N. LaSalle 
 Chicago,
Illinois 60654 
 Attn: Christian Nagler 

 Wayne Williams 

Email: cnagler@kirkland.com 

 wwilliams@kirkland.com 

and 
 Evercore Group L.L.C.

 55 East 52nd Street, Ste 35 

New York, New York 10055 
 Attn:
Kenneth Masotti 
 Email: masotti@evercore.com 

and 
 Bayclays Capital Inc.

 745 Seventh Avenue 
 New
York, New York 10019 
 Attn: Syndicate Registration 

and 

  
 8 













 David Polk & Wardell LLP 

450 Lexington Avenue 
 New York,
New York, 10017 
 Attn: Derek Dostal 

Deanna Kirkpatrick 

Email: derek.dostal@davispolk.com 

   deanna.kirkpatrick@davispolk.com 

This Agreement may not be assigned by the Trustee without the prior consent of the Company. 

(f) 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. 
 (g)
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. 

(h) 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. 

(i) Each of the Company and the Trustee hereby acknowledges and agrees that the Representatives on behalf of the Underwriters are third party
beneficiaries of this Agreement. 
 (j) 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] 

  
 9 













 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


  

			
	Post Holdings Partnering Corporation
		
	By:	 	        
		
	Name:	 	  

		
	Title:	 	  




  
 [Signature Page to
Investment Management Trust Agreement] 













 SCHEDULE A 
  

							
	 Fee Item
	  	 Time and method of payment
	  	Amount	 
			
	Initial acceptance fee	  	Initial closing of the Offering by wire transfer.	  	$	3,500.00	 
			
	Annual fee	  	First year fee payable at initial closing of the 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 Sections 1(i) and 1(j)	  	$	250.00	 
			
	Paying Agent services as required pursuant to Section 1(i) and 1(k)	  	Billed to Company upon delivery of service pursuant to Section 1(i) and 1(k)	  	 	Prevailing rates	 


  
 Schedule A-1 













 EXHIBIT A 

[Letterhead of Company] 

[Insert date] 
 Continental Stock
Transfer & Trust Company 
 One State Street, 30th Floor 

New York, New York 10004 
 Attn: Francis Wolf & 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 Post Holdings Partnering Corporation
(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 merger, share exchange, asset acquisition, share purchase, reorganization or similar partnering transaction with the Target Business (the “Partnering Transaction”) on or about
[insert date]. The Company shall notify you at least seventy-two (72) hours in advance of the actual date (or such shorter time period as you may agree) of the consummation of the Partnering
Transaction (“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 into the above-referenced trust operating account at J.P. Morgan Chase Bank, N.A. 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 Evercore Group L.L.C. and Barclays Capital Inc. (the “Representatives”) (with respect to the Deferred Discount) and the Company shall direct on the Consummation Date. 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, neither the Company nor the Representatives will earn any interest. 

On the Consummation Date (i) counsel for the Company shall deliver to you written notification that the Partnering Transaction 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 President, which verifies that the Partnering Transaction has been approved by a vote of the Company’s stockholders, if a vote is held and (b) 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 

  
 A-1 













 
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 Partnering Transaction 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 the notice as soon thereafter as possible. 
  

			
	        Very truly yours,
	
	Post Holdings Partnering Corporation
		
	By:	 	    
	Name:	 	  

	Title:	 	  



  

	cc:	 Evercore Group L.L.C. 



Barclays Capital Inc. 

  
 A-2 













 EXHIBIT B 

[Letterhead of Company] 

[Insert date] 
 Continental Stock
Transfer & Trust Company 
 One State Street, 30th Floor 

New York, New York 10004 
 Attn: Francis Wolf & 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 Post Holdings Partnering Corporation
(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 been unable to effect a merger, share exchange, asset acquisition, share purchase, reorganization or similar partnering transaction with a target
business (the “Partnering Transaction”) 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 operating account and to transfer the total proceeds into the trust operating account at J.P. Morgan Chase Bank, N.A. to await distribution to the Public
Stockholders. The Company has selected [•] 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 amended and restated certificate of incorporation of the Company.
Upon the distribution of all the funds, your obligations under the Trust Agreement shall be terminated, except to the extent otherwise provided in Section 1(j) of the Trust Agreement. 

 

			
	 Very truly yours,

	
	Post Holdings Partnering Corporation
		
	By:	 	        
	Name:	 	  

	Title:	 	  



  

	cc:	 Evercore Group L.L.C. 



	    	 Barclays Capital Inc. 



  
 B-1 













 EXHIBIT C 

[Letterhead of Company] 

[Insert date] 
 Continental Stock
Transfer & Trust Company 
 One State Street, 30th Floor 

New York, New York 
 10004 Attn: Francis Wolf & Celeste
Gonzalez 
  

	Re:	 Trust Account - Tax Payment Withdrawal Instruction 



Dear Mr. Wolf and Ms. Gonzalez: 

Pursuant to Section 1(j) of the Investment Management Trust Agreement between Post Holdings Partnering Corporation
(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,

	
	Post Holdings Partnering Corporation
		
	By:	 	        
	Name:	 	  

	Title:	 	  



  

	cc:	 Evercore Group L.L.C. 



Barclays Capital Inc. 

  
 C-1 













 EXHIBIT D 

[Letterhead of Company] 

[Insert date] 
 Continental Stock
Transfer & Trust Company 
 One State Street, 30th Floor 

New York, New York 10004 
 Attn: Francis Wolf & Celeste
Gonzalez 
 Dear Mr. Wolf and Ms. Gonzalez: 
  

	Re:	 Trust Account - Stockholder Redemption Withdrawal Instruction 



Pursuant to Section 1(k) of the Investment Management Trust Agreement between Post Holdings Partnering Corporation (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 on behalf of the Company
$                 of the principal and 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 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 (A) to modify the substance or timing of the
Company’s obligation to allow redemption in connection with the Company’s Partnering Transaction or to redeem 100% of the Company’s public shares if it does not complete its Partnering Transaction within such time as is described in
the Company’s amended and restated certificate of incorporation or (B) with respect to any other provision relating to stockholders’ rights or pre-Partnering Transaction activity. As such, you
are hereby directed and authorized to transfer (via wire transfer) such funds promptly upon your receipt of this letter to the redeeming Public Stockholders in accordance with your customary procedures. 

 

			
	 Very truly yours,

	
	Post Holdings Partnering Corporation
		
	By:	 	        
	Name:	 	  

	Title:	 	  



  

	cc:	 Evercore Group L.L.C. 



Barclays Capital Inc. 

  
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