Exhibit 10.2


 


[●], 2021


 


AltC Acquisition Corp.


640 Fifth Avenue, 12th Floor


New York, NY 10019


(212) 380-7500


 


Re:         Initial
Public Offering


 


Ladies and Gentlemen:


 


This letter (this “Letter Agreement”)
is being delivered to you in accordance with the Underwriting Agreement (the “Underwriting Agreement”) to be
entered into by and among AltC Acquisition Corp., a Delaware corporation (the “Company”)
and Citigroup Global Markets Inc. (the “Representative”), relating to an underwritten initial public offering
(the “Public Offering”), of 115,000,000 of the Company’s units (including up to 15,000,000 units that
may be purchased to cover over-allotments, if any) (the “Units”), each comprised of one share of the Company’s
Class A common stock, par value $0.0001 per share (the “Common Stock”), and one-sixth of one redeemable
warrant. Each whole Warrant (each, a “Warrant”) entitles the holder thereof to purchase one share of Common
Stock at a price of $11.50 per share, subject to adjustment. The Units will be sold in the Public Offering pursuant to a registration
statement on Form S-1 and prospectus (the “Prospectus”) filed by the Company with the U.S. Securities
and Exchange Commission (the “Commission”) and the Company has applied to have the Units listed on the New
York Stock Exchange. Certain capitalized terms used herein are defined in paragraph 11 hereof.


 


In order to induce the Company and the
Representative to enter into the Underwriting Agreement and to proceed with the Public Offering and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, [AltC Sponsor LLC (the “Insider”
or “Sponsor”)] [the undersigned, whom is a member of the Company’s board of directors and/or management
team (the “Insider”), hereby agrees with the Company as follows:


 


1.            The
Insider agrees with the Company that if the Company seeks stockholder approval of a proposed Business Combination, then in connection
with such proposed Business Combination, the Insider shall (i) vote any shares of Capital Stock owned by the Insider in favor
of any proposed Business Combination and (ii) not redeem any shares of Common Stock owned by the Insider in connection with
such stockholder approval. If the Company seeks to consummate a proposed Business Combination by engaging in a tender offer, the
Insider agrees that the Insider will not sell or tender any shares of Capital Stock owned by the Insider in connection therewith.


 






     


     


    

 


2.            The
Insider hereby agrees with the Company that in the event that the Company fails to consummate a Business Combination within 24
months from the closing of the Public Offering, or such later period approved by the Company’s stockholders in accordance
with the Company’s amended and restated certificate of incorporation (the “Charter”), the Insider shall
take all reasonable steps 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, subject to lawfully available funds therefor, redeem
100% of the Common Stock sold as part of the Units in the Public Offering (the “Offering Shares”), at a per-share
price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest (net of amounts
withdrawn to fund the Company’s working capital requirements, subject to an annual limit of $1,000,000, and/or to pay the
Company’s taxes (“Permitted Withdrawals”)) and less up to $100,000 of interest to pay dissolution expenses)),
divided by the number of then outstanding Offering Shares, which redemption will completely extinguish all Public Stockholders’
rights as stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law,
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, dissolve and liquidate, subject in each case to the Company’s obligations
under Delaware law to provide for claims of creditors and other requirements of applicable law. The Insider agrees to not propose
any amendment to the Charter that would modify the substance or timing of the Company’s obligation to redeem 100% of the
Offering Shares if the Company does not complete a Business Combination within the required time period set forth in the Charter
or with respect to any other material provisions relating to stockholders’ rights or pre-initial business combination activity,
unless the Company provides its Public Stockholders with the opportunity to redeem their Offering Shares upon approval of any
such amendment at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including
interest (net of Permitted Withdrawals), divided by the number of then outstanding Offering Shares.


 


The Insider acknowledges that
the Insider has no right, title, interest or claim of any kind in or to any monies held in the Trust Account as a result of any
liquidation of the Company with respect to the Founder Shares held by the Insider. The Insider hereby further waives, with respect
to any shares of Common Stock held by the Insider, if any, any redemption rights the Insider may have in connection with the consummation
of a Business Combination, including, without limitation, any such rights available in the context of a stockholder vote to approve
such Business Combination or in the context of a tender offer made by the Company to purchase shares of Common Stock (although
the Insider and the Insider’s affiliates shall be entitled to redemption and liquidation rights with respect to any Offering
Shares they hold if the Company fails to consummate a Business Combination within the time period set forth in the Charter or
in connection with a stockholder vote to approve an amendment to the Charter to modify the substance or timing of the Company’s
obligation to redeem 100% of the Offering Shares if the Company does not complete a Business Combination within the time period
set forth in the Charter or with respect to any other material provisions relating to stockholders' rights or pre-initial business
combination activity).


 






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3.            During
the period commencing on the effective date of the Underwriting Agreement and ending 180 days after such date, the Insider shall
not, without the prior written consent of the Representative, (i) sell, offer to sell, contract or agree to sell, hypothecate,
pledge, grant any option to purchase or otherwise dispose of or agree to dispose of, directly or indirectly, 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 Commission
promulgated thereunder, with respect to any Units, shares of Capital Stock, Warrants or any securities convertible into, or exercisable,
or exchangeable for, shares of Common Stock owned by the Insider, (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 Capital Stock, Warrants
or any securities convertible into, or exercisable, or exchangeable for, shares of Common Stock owned by the Insider, 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 specified in clause (i) or (ii). The Insider acknowledges and agrees that, prior to the
effective date of any release or waiver of the restrictions set forth in this paragraph 3 or paragraph 7 below, the Company shall
announce the impending release or waiver by press release through a major news service at least two business days before the effective
date of the release or waiver. Any such release or waiver granted shall only be effective two business days after the publication
date of such press release. The provisions of this paragraph will not apply if (i) the release or waiver is effected solely
to permit a transfer of securities without consideration and (ii) 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.


 


4.            In
the event of the liquidation of the Trust Account, [AltC Sponsor LLC (the “Sponsor”)] [the Sponsor] (which
for purposes of clarification shall not extend to any other shareholders, members or managers of the Sponsor) [has agreed] [agrees]
to indemnify and hold harmless the Company against any and all loss, liability, claim, damage and expense whatsoever (including,
but not limited to, any and all legal or other expenses reasonably incurred in investigating, preparing or defending against any
litigation, whether pending or threatened, or any claim whatsoever) to which the Company may become subject as a result of any
claim by (i) any third party for services rendered or products sold to the Company or (ii) any prospective target business
with which the Company has entered into a letter of intent, confidentiality or other similar agreement for a Business Combination
(a “Target”); provided, however, that such indemnification of the Company by the Sponsor (x) shall
apply only to the extent necessary to ensure that such claims by a third party or a Target do not reduce the amount of funds in
the Trust Account to below the lesser of (i) $10.00 per Offering Share or (ii) the actual amount per Offering Share
held in the Trust Account as of the date of the liquidation of the Trust Account, if less than $10.00 per Offering Share is then
held in the Trust Account due to reductions in the value of the trust assets less Permitted Withdrawals, (y) shall not apply
to any claims by a third party (including a Target) that executed a waiver of any and all rights to the monies held in the Trust
Account (whether or not such waiver is enforceable) and (z) shall not apply to any claims under the Company’s indemnity
of the Representative against certain liabilities, including liabilities under the Securities Act of 1933, as amended. The Sponsor
shall have the right to defend against any such claim with counsel of its choice reasonably satisfactory to the Company if, within
15 days following written receipt of notice of the claim to the Sponsor, the Sponsor notifies the Company in writing that it shall
undertake such defense. For the avoidance of doubt, none of the Company’s officers or directors will indemnify the Company
for claims by third parties, including, without limitation, claims by vendors and prospective target businesses.


 






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5.            To
the extent that the Representative does not exercise its over-allotment option to purchase up to an additional 15,000,000 Units
within 45 days from the date of the Prospectus (and as further described in the Prospectus), the Sponsor [agrees] [has agreed]
to forfeit, at no cost, a number of Founder Shares in the aggregate equal to the product of 3,750,000 multiplied by a fraction,
(i) the numerator of which is 15,000,000 minus the number of Units purchased by the Representative upon the exercise of its
over-allotment option, and (ii) the denominator of which is 15,000,000. The forfeiture will be adjusted to the extent that
the over-allotment option is not exercised in full by the Representative so that the Initial Stockholders will own an aggregate
of 20.0% of the Company’s issued and outstanding shares of Capital Stock after the Public Offering. To the extent that the
size of the Public Offering is increased or decreased, the Company will effect a capitalization or share repurchase, redemption
or stock split or other appropriate mechanism, as applicable, immediately prior to the consummation of the Public Offering in
such amount as to maintain the ownership of the Capital Stock of the Initial Stockholders prior to the Public Offering at 20.0%
of the Company’s issued and outstanding Capital Stock upon the consummation of the Public Offering. In connection with such
increase or decrease in the size of the Public Offering, (A) references to 15,000,000 in the numerator and denominator of
the formula in the first sentence of this paragraph shall be changed to a number equal to 15% of the number of shares included
in the Units issued in the Public Offering and (B) the reference to 3,750,000 in the formula set forth in the immediately
preceding sentence shall be adjusted to such number of Founder Shares that the Sponsor would have to return to the Company in
order to hold (with all of the Initial Stockholders) an aggregate of 20.0% of the Company’s issued and outstanding Capital
Stock after the Public Offering.


 


6.            (a)           The
Insider hereby agrees and acknowledges that: (i) the Representative and the Company would be irreparably injured in the event
of a breach by the Insider of the Insider’s obligations under paragraphs 1, 2, 3, 4, 5, 7(a), 7(b), and 9, as applicable,
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 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.            (a)           The
Insider agrees that the Insider shall not Transfer any Founder Shares (or shares of Common Stock issuable upon conversion thereof)
until the earlier of (A) one year after the completion of the Company’s initial Business Combination or (B) subsequent
to the Business Combination, (x) if the closing price of the Common Stock equals or exceeds $12.00 per share (as adjusted
for stock splits, stock dividends, 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, reorganization 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
(the “Founder Shares Lock-up Period”).


 






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(b)          The
Insider agrees that the Insider shall not 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 a Business Combination (the “Private
Placement Warrants Lock-up Period”, together with the Founder Shares Lock-up Period, the “Lock-up Periods”).


 


(c)           Notwithstanding
the provisions set forth in paragraphs 3 and 7(a) and (b), Transfers of the Founder Shares, Private Placement Warrants and
shares of Common Stock issued or issuable upon the exercise or conversion of the Private Placement Warrants or the Founder Shares
and that are held by the Insider or any of the Insider’s permitted transferees (that have complied with this paragraph 7(c)),
are permitted (a) to the Company’s officers or directors, any affiliates or family members of any of the Company’s
officers or directors, any members of the Insider, or any affiliates of the Insider; (b) in the case of an individual, transfers
by gift to a member of the individual’s immediate family, to a trust, the beneficiary of which is a member of the individual’s
immediate family or an affiliate of such person, or to a charitable organization; (c) in the case of an individual, transfers
by virtue of laws of descent and distribution upon death of the individual; (d) in the case of an individual, transfers pursuant
to a qualified domestic relations order; (e) transfers by private sales or transfers made in connection with the consummation
of a Business Combination at prices no greater than the price at which the securities were originally purchased; (f) transfers
in the event of the Company’s liquidation prior to the completion of an initial Business Combination; (g) transfers
by virtue of the laws of the State of Delaware or the Sponsor’s limited liability company agreement upon dissolution of
the Sponsor; (h) in the event of the Company’s completion of a liquidation, merger, stock exchange, reorganization
or other similar transaction which results in all of the Company’s public stockholders having the right to exchange their
shares of Class A common stock for cash, securities or other property subsequent to the completion of the initial business
combination; (i) to a nominee or custodian of a person or entity to whom a disposition or transfer would be permissible under
clauses (a) through (h) above; provided, however, that in the case of clauses (a) through (e) and
(i), these permitted transferees must enter into a written agreement with the Company agreeing to be bound by the transfer restrictions
herein and the other restrictions contained in this Agreement (including provisions relating to voting, the Trust Account and
liquidating distributions).


 


8.            The
Insider represents and warrants that the Insider 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. Each Insider’s
biographical information furnished to the Company (including any such information included in the Prospectus) is true and accurate
in all respects and does not omit any material information with respect to the Insider’s background. The Insider’s
questionnaire furnished to the Company is true and accurate in all respects. The Insider represents and warrants that: the Insider
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; the Insider has never been convicted
of, or pleaded guilty to, any crime (i) involving fraud, (ii) relating to any financial transaction or handling of funds
of another person, or (iii) pertaining to any dealings in any securities and the Insider is not currently a defendant in
any such criminal proceeding.


 






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9.             Except
as disclosed in the Prospectus, neither the Insider nor any affiliate of the Insider, shall receive from the Company any finder’s
fee, reimbursement, consulting fee, monies in respect of any repayment of a loan or other compensation prior to, or in connection
with any services rendered in order to effectuate the consummation of the Company’s initial Business Combination (regardless
of the type of transaction that it is), other than the following, none of which will be made from the proceeds held in the Trust
Account prior to the completion of the initial Business Combination: repayment of a loan and advances of up to $600,000 made to
the Company by the Sponsors to cover expenses related to the organization of the Company and the Public Offering; payment to M.
Klein and Company or another affiliate of the Sponsor for customary financial advisory fee; payment to M. Klein Associates, Inc.
for office space and related support services for a total of $50,000 per month; reimbursement for any reasonable out-of-pocket expenses
related to identifying, investigating and consummating an initial Business Combination, and repayment of loans, if any, and on
such terms as to be determined by the Company from time to time, made by the Sponsor or certain of the Company’s officers
and directors to finance transaction costs in connection with an intended initial Business Combination, provided, that, if the
Company does not consummate an initial Business Combination, a portion of the working capital held outside the Trust Account may
be used by the Company to repay such loaned amounts so long as no proceeds from the Trust Account are used for such repayment.
Up to $1,500,000 of such loans may be convertible into warrants of the post Business Combination entity at a price of $1.00 per
warrant at the option of the lender. Such warrants would be identical to the Private Placement Warrants, including as to exercise
price, exercisability and exercise period.


 


10.          The
Insider has full right and power, without violating any agreement to which the Insider is bound (including, without limitation,
any non-competition or non-solicitation agreement with any employer or former employer), to enter into this Letter Agreement and,
as applicable, to serve as an officer and/or a director on the board of directors of the Company and hereby consents to being
named in the Prospectus as an officer and/or a director of the Company.


 


11.           As
used herein, (i) “Business Combination” shall mean a merger, capital stock exchange, asset acquisition,
stock purchase, reorganization or similar business combination, involving the Company and one or more businesses; (ii) “Capital
Stock” shall mean, collectively, the Common Stock and the Founder Shares; (iii) “Founder Shares”
shall mean the 25,000,000 shares of the Company’s Class B common stock, par value $0.0001 per share, (or 28,750,000
shares if the over-allotment option is not exercised by the Representative) initially held by the Sponsor; (iv) “Initial
Stockholders” shall mean the Sponsor and any other holder of Founder Shares immediately prior to the Public Offering;
(v) “Private Placement Warrants” shall mean the warrants to purchase up to 25,000,000 shares of Common
Stock of the Company (or 28,000,000 shares of Common Stock if the over-allotment option is exercised in full) that the Sponsor
has agreed to purchase for an aggregate purchase price of $25,000,000 in the aggregate (or $28,000,000 if the over-allotment option
is exercised in full), or $1.00 per warrant, in a private placement that shall occur simultaneously with the consummation of the
Public Offering; (vi) “Public Stockholders” shall mean the holders of securities issued in the Public
Offering; (vii) “Trust Account” shall mean the trust fund into which a portion of the net proceeds of
the Public Offering and the sale of the Private Placement Warrants shall be deposited; and (viii) “Transfer”
shall mean the (a) sale or assignment 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).


 






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12.           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.


 


13.           Except
as otherwise provided herein, no party hereto may assign either this Letter Agreement or any of its rights, interests, or obligations
hereunder without the prior written consent of the other parties. 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. This Letter
Agreement shall be binding on the Insider and the Insider’s successors, heirs and assigns and permitted transferees.


 


14.           Nothing
in this Letter Agreement shall be construed to confer upon, or give to, any person or entity other than the parties hereto any
right, remedy or claim under or by reason of this Letter Agreement or of any covenant, condition, stipulation, promise or agreement
hereof. All covenants, conditions, stipulations, promises and agreements contained in this Letter Agreement shall be for the sole
and exclusive benefit of the parties hereto and their successors, heirs, personal representatives and assigns and permitted transferees.


 


15.           This
Letter Agreement may be executed in any number of original or facsimile counterparts and each of such counterparts shall for all
purposes be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument.


 






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16.           This
Letter Agreement shall be deemed severable, and the invalidity or unenforceability of any term or provision hereof shall not affect
the validity or enforceability of this Letter Agreement or of any other term or provision hereof. Furthermore, in lieu of any
such invalid or unenforceable term or provision, the parties hereto intend that there shall be added as a part of this Letter
Agreement a provision as similar in terms to such invalid or unenforceable provision as may be possible and be valid and enforceable.


 


17.           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 parties hereto (i) all agree that any action, proceeding, claim or dispute arising out of, or relating in any way to,
this Letter Agreement shall be brought and enforced in the courts of New York City, in the State of New York, and irrevocably
submit to such jurisdiction and venue, which jurisdiction and venue shall be exclusive and (ii) waive any objection to such
exclusive jurisdiction and venue or that such courts represent an inconvenient forum.


 


18.           Any
notice, consent or request to be given in connection with any of the terms or provisions of this Letter 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 facsimile transmission.


 


19.           This
Letter Agreement shall terminate on the earlier of (i) the expiration of the Lock-up Periods or (ii) the liquidation
of the Company; provided, however, that this Letter Agreement shall earlier terminate in the event that the Public
Offering is not consummated and closed by [●], 2021; provided further that paragraph 4 of this Letter Agreement shall
survive such liquidation for a period of six years.


 


[Signature Page Follows]


 






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	 	Sincerely,
	 	 
	 	[ALTC SPONSOR LLC
	 	 
	 	By:	 
	 	 	Name:
	 	 	Title: ]






 


[Signature Page to Letter Agreement]


 






    


     


    

 


	 	 
	 	[D&O Name]1




 





 






1
Each Insider to sign separate agreement.


 


[Signature Page to Letter
Agreement]


 






    


     


    

 


Acknowledged and Agreed:


 


ALTC ACQUISITION CORP.


 


	By:	 	 
	 	Name: 	 
	 	Title:	 






 


[Signature Page to Letter Agreement]