EX-10.9






 Exhibit 10.9 

____________, 2021 
 Brimstone Acquisition
Holdings Corp. 
 500 South Pointe Drive, Suite 240 
 Miami
Beach, FL 33139 
 Citigroup Global Markets Inc. 
 Credit
Suisse Securities (USA) LLC 
 UBS Securities LLC 
 as
Representatives (as defined below) of the several Underwriters 
 listed in Schedule I to the Underwriting Agreement (as defined below) 

c/o Citigroup Global Markets Inc. 
 388 Greenwich Street 

New York, New York 10013 
 c/o Credit Suisse Securities
(USA) LLC 
 Eleven Madison Avenue 
 New York, NY 10010 

c/o UBS Securities LLC 
 1285 Avenue of the Americas 

New York, New York 10019 
  

	Re:                Initial	 Public Offering 



Ladies and Gentlemen: 
 This letter (the “Letter
Agreement”) is being delivered to you in accordance with the Underwriting Agreement (the “Underwriting Agreement”) entered into by and between Brimstone Acquisition Holdings Corp., a Delaware corporation (the
“Company”) and Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC and UBS Securities LLC, as representatives (the “Representatives”) of the several underwriters named in Schedule A
thereto (the “Underwriters”), relating to an underwritten initial public offering (the “IPO”) of the Company’s units (the “Units”), each unit comprised of one share of the
Company’s Class A common stock, par value $0.0001 per share (the “Common Stock”), and one-fourth of one redeemable warrant, each whole warrant exercisable for one share of
Common Stock (each, a “Warrant”). Certain capitalized terms used herein are defined in paragraph 12 hereof. 
 In order to induce
the Company and the Underwriters to enter into the Underwriting Agreement and to proceed with the IPO, and in recognition of the benefit that such IPO will confer upon the undersigned, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the undersigned hereby agrees with the Company as follows: 
  

	 	1.	 If the Company solicits approval of its stockholders of a Business Combination, the undersigned will vote all
shares of Common Stock beneficially owned by him or her, whether acquired before, in or after the IPO, in favor of such Business Combination. 


  

	 	2.	 In the event that the Company does not complete a Business Combination within the time period set forth in the
Company’s amended and restated certificate of incorporation, as the same may be further amended from time to time (the “Charter”), the undersigned will, as promptly as possible, take all necessary actions to cause the
Company to (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible, but not more than 10 business days thereafter, redeem the IPO Shares, at a per-share



  













 price, payable in cash, equal to the aggregate amount then on deposit 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 tax obligations, if any (less up to $100,000 of interest to pay dissolution expenses), divided by the number of the then
outstanding IPO Shares, which redemption will completely extinguish public stockholders’ rights as stockholders (including the right to receive further liquidation distributions, if any), and (iii) as promptly as reasonably possible
following such redemption, subject to the approval of the Company’s remaining stockholders and the Company’s board of directors, liquidate and dissolve , subject in each case to the Company’s obligations under Delaware law to provide
for claims of creditors and the requirements of other applicable law. The undersigned hereby waives any and all right, title, interest or claim of any kind in or to any distribution of the Trust Account and any remaining net assets of the Company as
a result of such liquidation with respect to the Founder Shares owned by the undersigned. However, if any of the undersigned have acquired IPO Shares in or after the IPO, they will be entitled to liquidating distributions from the Trust Account with
respect to such IPO Shares in the event that the Company does not complete a Business Combination within the time period set forth in the Charter. The undersigned acknowledges and agrees that there will be no distribution from the Trust Account with
respect to any Warrants, all rights of which will terminate on the Company’s liquidation. 
  

	 	3.	 The undersigned acknowledges and agrees that prior to entering into a definitive agreement for a Business
Combination with a target business that is affiliated with the undersigned or any other Insiders of the Company or their affiliates, such transaction must be approved by a majority of the Company’s disinterested independent directors and the
Company must obtain an opinion from an independent investment banking firm, which is a member of the Financial Industry Regulatory Authority, or an independent accounting firm that such Business Combination is fair to the Company’s unaffiliated
stockholders from a financial point of view. 


  

	 	4.	 None of the undersigned, any member of the family of any of the undersigned, or any affiliate of the
undersigned will be entitled to receive and will not accept any compensation or other cash payment from the Company prior to, or for services rendered in order to effectuate, the completion of the Business Combination; provided that the Company
shall be allowed to make the payments set forth in the Registration Statement adjacent to the caption “Prospectus Summary—The Offering—Limited payments to insiders.” 



 

	 	5.	 (a) The undersigned agrees not to Transfer the Founder Shares (or any shares of Common Stock issuable upon
conversion therof) (except to certain permitted transferees as described in the Registration Statement or herein) (the “Lockup”) until the earlier to occur of: (1) one year after the completion of the Company’s
initial Business Combination or (2) subsequent to the Company’s initial Business Combination, (x) if the last reported sale price of Common Stock equals or exceeds $12.00 per share (as adjusted for stock splits, stock capitalizations,
reorganizations, recapitalizations and the like) for any 20 trading days within any 30-trading day period commencing at least 150 days after the Company’s initial Business Combination or (y) the date
on which the Company completes a liquidation, merger, capital stock exchange or other similar transaction that results in all of the Company’s stockholders having the right to exchange their shares of common stock for cash, securities or other
property. 


  

	 	(b)	 Notwithstanding the provisions set forth in paragraphs 5(a) and 5(c), during the period commencing on the
effective date of the Underwriting Agreement and ending 180 days after such date, the undersigned will not, without the prior written consent of the Representatives pursuant to the Underwriting Agreement, (i) sell, offer to sell, contract or
agree to sell, hypothecate, pledge, hedge or otherwise dispose of or agree to dispose of (or enter into any transaction that is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective
economic disposition due to cash settlement or otherwise) by the undersigned or any affiliate of the undersigned or any person in privity with the undersigned or any affiliate of the undersigned), directly or indirectly, including the filing (or
participation in the filing) of a registration statement with the Securities and Exchange Commission (the “SEC”) in respect of, or establish or increase a put equivalent position or liquidate or decrease a call equivalent
position within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) and the rules and regulations of the SEC promulgated thereunder with respect to, any Units, shares of
Common Stock, Founder Shares or Warrants or any securities convertible into, or 
















	 	
exercisable, or exchangeable for, shares of Common Stock owned by it, him or her, (ii) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the
economic consequences of ownership of any Units, shares of Common Stock, Founder Shares, Warrants or any securities convertible into, or exercisable, or exchangeable for, shares of Common Stock owned by it, him or her, whether any such transaction
is to be settled by delivery of such securities, in cash or otherwise, or (iii) publicly announce any intention to effect any transaction, including the filing of a registration statement, specified in clause (i) or (ii). The provisions of
this paragraph will not apply (i) to the transfer of Founder Shares to any independent director appointed or elected to the Company’s board of directors before or after the IPO or (ii) if the release or waiver is effected solely to
permit a transfer not for consideration and, in each case the transferee has agreed in writing to be bound by the same terms described in this Letter Agreement to the extent and for the duration that such terms remain in effect at the time of the
transfer. 

  

	 	(c)	 The undersigned agrees not to Transfer any Private Placement Warrants (or shares of Common Stock issued or
issuable upon the exercise of the Private Placement Warrants), until 30 days after the completion of the Company’s initial Business Combination. 


  

	 	(d)	 Notwithstanding the provisions set forth in paragraphs 5(a) and (c), Transfers by the undersigned of the
Founder Shares, Private Placement Warrants and shares of Common Stock issued or issuable upon the exercise of the Private Placement Warrants or conversion of the Founder Shares are permitted (i) to the Company’s officers or directors, any
affiliates or family members of any of the Company’s officers or directors, to Brimstone Acquisition Founder LLC, a Delaware limited liability company (the “Sponsor”), any members of the Sponsor or their affiliates, any
affiliates of the Sponsor, or any employees of such affiliates; (ii) in the case of an individual, by gift to a member of the individual’s immediate family or to a trust, the beneficiary of which is a member of one of the individual’s
immediate family, an affiliate of such person or to a charitable organization; (iii) in the case of an individual, by virtue of laws of descent and distribution upon death of the individual; (iv) in the case of an individual, pursuant to a
qualified domestic relations order; (v) by private sales or transfers made in connection with the completion of the Business Combination at prices no greater than the price at which the Founder Shares, Private Placement Warrants or shares of
Common Stock, as applicable, were originally purchased; (vi) by virtue of the Sponsor’s organizational documents upon liquidation or dissolution of the Sponsor; (vii) to the Company for no value for cancellation in connection with the
completion of the Business Combination; (viii) in the event of the Company’s liquidation prior to the completion of a Business Combination; or (ix) in the event of completion of a liquidation, merger, share exchange or other similar
transaction which results in all of the Company’s stockholders having the right to exchange their shares of Common Stock for cash, securities or other property subsequent to the completion of a Business Combination; provided,
however, that in the case of clauses (i) through (vi) these permitted transferees must enter into a written agreement agreeing to be bound by the restrictions herein. For the avoidance of doubt, the transfers of Founder Shares, Private
Placement Warrants and shares of Common Stock issued or issuable upon the exercise of the Private Placement Warrants or conversion of the Founder Shares shall be permitted regardless of whether a filing under Section 16(a) of the Exchange Act
shall be required or shall be voluntarily made with respect to such transfers. 


  

	 	(e)	 The undersigned acknowledges and agrees that if, in order to complete any Business Combination, the holders of
Founder Shares or Private Placement Warrants are required to contribute back to the capital of the Company a portion of any such securities to be cancelled by the Company or transfer any such securities to third parties, the undersigned will
contribute back to the capital of the Company or transfer to such third parties, at no cost, a proportionate number of Founder Shares or Private Placement Warrants, as applicable, pro rata with the other holders of Founder Shares or Private
Placement Warrants, as applicable. 


  

	 	6.	 Each Insider hereby agrees and acknowledges that: (i) the Underwriters and the Company would be
irreparably injured in the event of a breach by such Insider of his or her obligations under paragraphs 1, 2, 3, 4, 5, 7, 10 and 11 of this Letter Agreement (ii) monetary damages may not be an adequate remedy for such breach and (iii) the non-breaching party shall be entitled to seek injunctive relief, in addition to any other remedy that such party may have in law or in equity, in the event of such breach. 
















	 	7.	 In order to minimize potential conflicts of interest that may arise from multiple corporate affiliations, the
undersigned hereby agrees that until the earliest of the Company’s initial Business Combination or liquidation, the undersigned shall present to the Company for its consideration, prior to presentation to any other entity, any target business
that has a fair market value of at least 80% of the assets held in the Trust Account (excluding the amount of deferred underwriting discounts held in trust and taxes payable on the interest earned on the trust account), subject to any existing or
future fiduciary or contractual obligations the undersigned might have. 


  

	 	8.	 The undersigned agrees to be a director or officer of the Company, as applicable, until the earlier of the
completion by the Company of an initial Business Combination, the liquidation of the Company, or his or her removal, death or incapacity. In the event of the removal or resignation of the undersigned as a director or officer (as applicable), the
undersigned agrees that he or she will not, prior to the completion of the Business Combination, without the prior express written consent of the Company, (i) use for the benefit of the undersigned or to the detriment of the Company or
(ii) disclose to any third party (unless required by law or governmental authority), any information regarding a potential target of the Company that is not generally known by persons outside of the Company, the Sponsor, or their respective
affiliates. The undersigned’s biographical information previously furnished to the Company and the Representatives is true and accurate in all material respects, does not omit any material information with respect to the undersigned’s
background and contains all of the information required to be disclosed pursuant to Item 401 of Regulation S-K, promulgated under the Securities Act of 1933, as amended. The undersigned’s FINRA
Questionnaire previously furnished to the Company and the Representatives is true and accurate in all material respects. The undersigned represents and warrants that: 



 

	 	(a)	 He or she is not subject to, or a respondent in, any legal action for, any injunction, cease-and-desist order or order or stipulation to desist or refrain from any act or practice relating to the offering of securities in any jurisdiction; 



 

	 	(b)	 He or she has never been convicted of or pleaded guilty to any crime (i) involving any fraud or
(ii) relating to any financial transaction or handling of funds of another person, or (iii) pertaining to any dealings in any securities and he is not currently a defendant in any such criminal proceeding; and 



 

	 	(c)	 He or she has never been suspended or expelled from membership in any securities or commodities exchange or
association or had a securities or commodities license or registration denied, suspended or revoked. 


  

	 	9.	 The undersigned has full right and power, without violating any agreement by which he or she is bound, to enter
into this Letter Agreement and to serve as a director or officer of the Company, as applicable. 


  

	 	10.	 The undersigned hereby waives his or her right to exercise redemption rights with respect to any of the
Company’s shares of Common Stock owned or to be owned by the undersigned, directly or indirectly, whether such shares be part of the Founder Shares or IPO Shares, and agrees that he or she will not seek redemption with respect to such shares
(or sell such shares to the Company in any tender offer) in connection with any stockholder vote to approve (x) a Business Combination or (y) an amendment to the Charter that would affect the substance or timing of the Company’s
obligation to allow redemption in connection with the Business Combination or to redeem 100% of the shares of Common Stock if the Company has not completed a Business Combination within 24 months from the closing of the IPO. 



 

	 	11.	 The undersigned hereby agrees to not propose, or vote in favor of, an amendment to Section 9.2(d) of the
Charter prior to the completion of a Business Combination unless the Company provides public stockholders with the opportunity to redeem their shares of Common Stock upon such approval in accordance with such Section 9.2(d) thereof.



  

	 	12.	 This Letter 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. The undersigned hereby (i) agrees that any action, proceeding or claim against him arising
out of or relating in any way to this Letter Agreement shall be 
















	 	
brought and enforced in the courts of the State of New York of the United States of America for the Southern District of New York, and irrevocably submits to such jurisdiction, which jurisdiction
shall be exclusive and (ii) waives any objection to such exclusive jurisdiction and that such courts represent an inconvenient forum. 

  

	 	13.	 As used herein, (i) a “Business Combination” shall mean a merger, stock exchange,
asset acquisition, stock purchase, recapitalization, reorganization or other similar business combination with one or more businesses or entities; (ii) “Insiders” shall mean all officers, directors and sponsors of the Company
immediately prior to the IPO; (iii) “Founder Shares” shall mean all of the Class B common stock of the Company, par value $0.0001 per share, acquired by an Insider prior to the IPO; (iv) “IPO
Shares” shall mean the shares of Common Stock issued in the Company’s IPO; (v) “Private Placement Warrants” shall mean the warrants that are being sold privately by the Company simultaneously with the
consummation of the IPO; (vii) “Transfer” shall mean the (a) sale of, offer to sell, contract or agreement to sell, hypothecate, pledge, grant of any option to purchase or otherwise dispose of or agreement to dispose of,
directly or indirectly, or establishment or increase of a put equivalent position or liquidation with respect to or decrease of a call equivalent position within the meaning of Section 16 of the Exchange Act, and the rules and regulations
of the Commission promulgated thereunder with respect to, any security, (b) entry into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of any security, whether any such
transaction is to be settled by delivery of such securities, in cash or otherwise, or (c) public announcement of any intention to effect any transaction specified in clause (a) or (b); (vii) “Trust Account”
shall mean the trust account into which the net proceeds of the Company’s IPO and a portion of the proceeds from the sale of the Private Placement Warrants will be deposited; and (viii) “Registration Statement” means the
Company’s registration statement on Form S-1 (SEC File No. 333-254118) filed with the SEC, as amended. 



 

	 	14.	 This Letter Agreement constitutes the entire agreement and understanding of the parties hereto in respect of
the subject matter hereof and supersedes all prior understandings, agreements, or representations by or among the parties hereto, written or oral, to the extent they relate in any way to the subject matter hereof or the transactions contemplated
hereby. This Letter Agreement may not be changed, amended, modified or waived (other than to correct a typographical error) as to any particular provision, except by a written instrument executed by all parties hereto. 



 

	 	15.	 The undersigned acknowledges and understands that the Underwriters and the Company will rely upon the
agreements, representations and warranties set forth herein in proceeding with the IPO. Nothing contained herein shall be deemed to render any Underwriter, a representative of, or a fiduciary with respect to, the Company, its stockholders or any
creditor or vendor of the Company with respect to the subject matter hereof. 


  

	 	16.	 This Letter Agreement shall be binding on the undersigned and such person’s respective successors, heirs,
personal representatives and assigns. This Letter Agreement shall terminate on the earlier of (i) the completion of a Business Combination and (ii) the liquidation of the Company; provided, that such termination shall not relieve the
undersigned from liability for any breach of this agreement prior to its termination. The parties hereto may not assign either this Letter Agreement or any of their rights, interests, or obligations hereunder without the prior written consent of the
other party. Any purported assignment in violation of this paragraph shall be void and ineffectual and shall not operate to transfer or assign any interest or title to the purported assignee. 



[Signature Page Follows] 













 
			
	Sincerely,


 
			
		
	By:	 	  



 
			
	Name of Insider:















 
			
	Acknowledged and Agreed:
	
	BRIMSTONE ACQUISITION HOLDINGS CORP.


 
			
		
	By:	 	  



 
			
	Name:	 	
	Title: