Exhibit 4.3


 


Form of Warrant Certificate


 


[FACE]


 


Number


 


Warrants


 


THIS WARRANT SHALL BE VOID IF NOT EXERCISED
PRIOR TO


 


THE EXPIRATION OF THE EXERCISE PERIOD
PROVIDED FOR


 


IN THE WARRANT AGREEMENT DESCRIBED
BELOW


 


ALTITUDE ACQUISITION CORP. III


 


Incorporated Under the Laws of the State
of Delaware


 


CUSIP 02157P 119


 


Warrant Certificate


 


This Warrant Certificate certifies
that __________________, or registered assigns, is the registered holder of warrant(s) evidenced hereby (the “Warrants”
and each, a “Warrant”) to purchase shares of Class A common stock, $0.0001 par value per share (“Class
A Common Stock”), of Altitude Acquisition Corp. III, a Delaware corporation (the “Company”).
Each whole Warrant entitles the holder, upon exercise during the period set forth in the Warrant Agreement referred to below, to
receive from the Company that number of fully paid and non-assessable shares of Class A Common Stock as set forth below, at the
exercise price (the “Warrant Price”) as determined pursuant to the Warrant Agreement, payable in lawful
money (or through “cashless exercise” as provided for in the Warrant Agreement) of the United States
of America upon surrender of this Warrant Certificate and payment of the Warrant Price at the office or agency of the Warrant Agent
referred to below, subject to the conditions set forth herein and in the Warrant Agreement. Defined terms used in this Warrant
Certificate but not defined herein shall have the meanings given to them in the Warrant Agreement.


 


Each whole Warrant is initially exercisable
for one fully paid and non-assessable share of Class A Common Stock. No fractional shares will be issued upon exercise of any Warrant.
If, upon the exercise of Warrants, a holder would be entitled to receive a fractional interest in a share of Class A Common Stock,
the Company will, upon exercise, round down to the nearest whole number the number of shares of Class A Common Stock to be issued
to the Warrant holder. The number of shares of Class A Common Stock issuable upon exercise of the Warrants is subject to adjustment
upon the occurrence of certain events set forth in the Warrant Agreement.


 


The initial Warrant Price per share of
Class A Common Stock for any Warrant is equal to $11.50 per share. The Warrant Price is subject to adjustment upon the occurrence
of certain events set forth in the Warrant Agreement. The Warrants may be redeemed, subject to certain conditions, as set forth
in the Warrant Agreement.


 


Subject to the conditions set forth in
the Warrant Agreement, the Warrants may be exercised only during the Exercise Period and to the extent not exercised by the end
of such Exercise Period, such Warrants shall become void.


 






     


     


    

 


Reference is hereby made to the further
provisions of this Warrant Certificate set forth on the reverse hereof and such further provisions shall for all purposes have
the same effect as though fully set forth at this place.


 


This Warrant Certificate shall not be valid
unless countersigned by the Warrant Agent, as such term is used in the Warrant Agreement.


 


This Warrant Certificate shall be governed
by and construed in accordance with the internal laws of the State of New York.


 


	 	ALTITUDE ACQUISITION CORP. III
	 	 	 
	 	By:	 
	 	 	 
	 	Name:	 
	 	 	 
	 	Title:	 
	 	 	 
	 	CONTINENTAL STOCK TRANSFER & TRUST COMPANY,
	 	as Warrant Agent
	 	 	 
	 	By:	                                 
	 	 	 
	 	Name: 	 
	 	 	 
	 	Title:	 


 


[Signature Page to Warrant Certificate]


 




    2


     


    

 


[Form of Warrant Certificate]


 


[Reverse]


 


The Warrants evidenced by this Warrant
Certificate are part of a duly authorized issue of Warrants entitling the holder on exercise to receive shares of Class A Common
Stock and are issued or to be issued pursuant to a Warrant Agreement dated as of ________, 2021 (the “Warrant Agreement”),
duly executed and delivered by the Company to Continental Stock Transfer & Trust Company, a New York corporation, as warrant
agent (the “Warrant Agent”), which Warrant Agreement is hereby incorporated by reference in and made
a part of this instrument and is hereby referred to for a description of the rights, limitation of rights, obligations, duties
and immunities thereunder of the Warrant Agent, the Company and the holders (the words “holders” or “holder”
meaning the Registered Holders or Registered Holder, respectively) of the Warrants. A copy of the Warrant Agreement may be obtained
by the holder hereof upon written request to the Company. Defined terms used in this Warrant Certificate but not defined herein
shall have the meanings given to them in the Warrant Agreement.


 


Warrants may be exercised at any time during
the Exercise Period set forth in the Warrant Agreement. The holder of Warrants evidenced by this Warrant Certificate may exercise
them by surrendering this Warrant Certificate, with the form of election to purchase set forth hereon properly completed and executed,
together with payment of the Warrant Price as specified in the Warrant Agreement (or through “cashless exercise” as
provided for in the Warrant Agreement) at the principal corporate trust office of the Warrant Agent. In the event that upon any
exercise of Warrants evidenced hereby the number of Warrants exercised shall be less than the total number of Warrants evidenced
hereby, there shall be issued to the holder hereof or his, her or its assignee, a new Warrant Certificate evidencing the number
of Warrants not exercised.


 


Notwithstanding anything else in this Warrant
Certificate or the Warrant Agreement, no Warrant may be exercised unless at the time of exercise (i) a registration statement covering
the shares of Class A Common Stock to be issued upon exercise is effective under the Securities Act and (ii) a prospectus thereunder
relating to the shares of Class A Common Stock is current, except through “cashless exercise” as provided for in the
Warrant Agreement.


 


The Warrant Agreement provides that upon
the occurrence of certain events the number of shares of Class A Common Stock issuable upon exercise of the Warrants set forth
on the face hereof may, subject to certain conditions, be adjusted. If, upon exercise of a Warrant, the holder thereof would be
entitled to receive a fractional interest in a share of Class A Common Stock, the Company shall, upon exercise, round down to the
nearest whole number of shares of Class A Common Stock to be issued to the holder of the Warrant.


 


Warrant Certificates, when surrendered
at the principal corporate trust office of the Warrant Agent by the Registered Holder thereof in person or by legal representative
or attorney duly authorized in writing, may be exchanged, in the manner and subject to the limitations provided in the Warrant
Agreement, but without payment of any service charge, for another Warrant Certificate or Warrant Certificates of like tenor evidencing
in the aggregate a like number of Warrants.


 


Upon due presentation for registration
of transfer of this Warrant Certificate at the office of the Warrant Agent a new Warrant Certificate or Warrant Certificates of
like tenor and evidencing in the aggregate a like number of Warrants shall be issued to the transferee(s) in exchange for this
Warrant Certificate, subject to the limitations provided in the Warrant Agreement, without charge except for any tax or other governmental
charge imposed in connection therewith.


 


The Company and the Warrant Agent may deem
and treat the Registered Holder(s) hereof as the absolute owner(s) of this Warrant Certificate (notwithstanding any notation of
ownership or other writing hereon made by anyone), for the purpose of any exercise hereof, of any distribution to the holder(s)
hereof, and for all other purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary.
Neither the Warrants nor this Warrant Certificate entitles any holder hereof to any rights of a stockholder of the Company.


 






    3


     


    

 


Election to Purchase


 


(To Be Executed Upon Exercise of Warrant)


 


The undersigned hereby irrevocably elects
to exercise the right, represented by this Warrant Certificate, to receive _____ shares of Class A Common Stock and herewith tenders
payment for such shares of Class A Common Stock to the order of Altitude Acquisition Corp. III (the “Company”)
in the amount of $__________ in accordance with the terms hereof. The undersigned requests that a certificate for such shares of
Class A Common Stock be registered in the name of ________________________, whose address is and that such shares of Class A Common
Stock be delivered to _____________________________ whose address is ________________________. If said number of shares of Class
A Common Stock is less than all of the shares of Class A Common Stock purchasable hereunder, the undersigned requests that a new
Warrant Certificate representing the remaining balance of such shares of Class A Common Stock be registered in the name of ________________________,
whose address is ________________________ and that such Warrant Certificate be delivered to _________________, whose address is
________________________.


 


In the event that the Warrant has been
called for redemption by the Company pursuant to Section 6.1 or 6.2 of the Warrant Agreement and the Company has
required cashless exercise pursuant to Section 6.4 of the Warrant Agreement, the number of shares of Class A Common Stock
that this Warrant is exercisable for shall be determined in accordance with subsection 3.3.1(b) and Section 6.4 of
the Warrant Agreement.


 


In the event that the Warrant is a Private
Placement Warrant or a Working Capital Warrant that is to be exercised on a “cashless” basis pursuant to subsection
3.3.1(c) of the Warrant Agreement, the number of shares of Class A Common Stock that this Warrant is exercisable for shall
be determined in accordance with subsection 3.3.1(c) of the Warrant Agreement.


 


In the event that the Warrant is to be
exercised on a “cashless” basis pursuant to Section 7.4 of the Warrant Agreement, the number of shares of Class
A Common Stock that this Warrant is exercisable for shall be determined in accordance with Section 7.4 of the Warrant Agreement.


 


In the event that the Warrant may be exercised,
to the extent allowed by the Warrant Agreement, through cashless exercise (i) the number of shares of Class A Common Stock that
this Warrant is exercisable for would be determined in accordance with the relevant section of the Warrant Agreement which allows
for such cashless exercise and (ii) the holder hereof shall complete the following: The undersigned hereby irrevocably elects to
exercise the right, represented by this Warrant Certificate, through the cashless exercise provisions of the Warrant Agreement,
to receive shares of Class A Common Stock. If said number of shares of Class A Common Stock is less than all of the shares of Class
A Common Stock purchasable hereunder (after giving effect to the cashless exercise), the undersigned requests that a new Warrant
Certificate representing the remaining balance of such shares of Class A Common Stock be registered in the name of ________________________,
whose address is ________________________ and that such Warrant Certificate be delivered to _____________________________, whose
address is ________________________.


 


[Signature Page Follows]


 




    4


     


    

 


Date:     , 2021


 


	 	Signature
	 	 
	 	(Address)
	 	 
	 	(Tax Identification Number)


 


	Signature Guaranteed:	 	 
	 	 	 
	 	 	 


 


THE SIGNATURE(S) SHOULD BE GUARANTEED BY
AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED
SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15 UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED (OR
ANY SUCCESSOR RULE)).


 


 


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