Exhibit 10.4


 


November 12, 2020


 


Health Assurance Acquisition Corp.

20 University Road

Cambridge, Massachusetts 02138


 


Morgan Stanley & Co. LLC


1585 Broadway

New York, New York 10036


 


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 between Health Assurance Acquisition Corp., a Delaware corporation (the “Company”),
and Morgan Stanley & Co. LLC (the “Underwriter”), relating to an underwritten initial public offering
(the “Public Offering”), of 57,500,000 of the Company’s SAILSM securities (including
up to 7,500,000 SAILSM securities granted to the Underwriter that may be purchased to cover over-allotments, if any)
(the “SAILSM securities”), each comprised of one share of the Company’s Class A
common stock, par value $0.0001 per share (the “Class A Common Stock”), and one-fourth of one redeemable
warrant. Each whole Warrant (each, a “Warrant”) entitles the holder thereof to purchase one share of
Class A Common Stock at a price of $11.50 per share, subject to adjustment. The SAILSM securities will be sold in the
Public Offering pursuant to a registration statement on Form S-1 and a prospectus (the “Prospectus”)
included therein, filed by the Company with the Securities and Exchange Commission (the “Commission”)
and the Company has applied to have the SAILSM securities listed on the Nasdaq Capital Market. Certain capitalized terms
used herein are defined in paragraph 12 hereof.


 


In order to induce the Company and the Underwriter
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, HAAC Sponsor, LLC, a Delaware limited liability company (the “Sponsor”),
Health Assurance Economy Foundation (the “Foundation”) and the undersigned individuals, each of whom
is a member of the Company’s board of directors, a nominee for membership on the board of directors and/or an executive officer
of the Company’s (each, an “Insider” and collectively, the “Insiders”),
hereby agrees with the Company as follows:


 


1.                 
It is acknowledged and agreed that the Company shall not enter into a definitive agreement regarding a proposed Business
Combination without the prior consent of the Sponsor. The Sponsor, the Foundation and each Insider agrees that if the Company seeks
stockholder approval of a proposed Business Combination, then in connection with such proposed Business Combination, it, he or
she shall (i) vote any shares of capital stock owned by it, him or her in favor of any proposed Business Combination and (ii) not
redeem any shares of Class A Common Stock owned by it, him or her in connection with such stockholder approval. If the Company
seeks to consummate a proposed Business Combination by engaging in a tender offer, the Sponsor, the Foundation and each Insider
agrees that it, he or she will not sell or tender any shares of Class A Common Stock owned by it, him or her in connection therewith.


 






     


     


    

 


2.                 
The Sponsor, the Foundation and each Insider hereby agrees 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 Sponsor, the Foundation and each
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 Class A Common Stock sold as part of the SAILSM securities 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 earned on the funds held in the Trust Account and not previously released to the Company
to pay franchise and income taxes (less up to $100,000 of such net 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 liquidation 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 Sponsor, the Foundation and each Insider agrees
to not propose any amendment to the Company’s amended and restated certificate of incorporation that would affect 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 24 months from the closing of the Public Offering or with respect to any other provisions relating to the rights of holders
of our Class A Common Stock, 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 earned on the funds held in the Trust Account and not previously released to the Company
to pay its franchise and income taxes, divided by the number of then outstanding Offering Shares.


 


The Sponsor, the Foundation and each Insider
acknowledges that it or he or she has no right, title, interest or claim of any kind in or to any monies held in the Trust Account
or any other asset of the Company as a result of any liquidation of the Company with respect to the Alignment
Shares held by it. The Sponsor, the Foundation and each Insider hereby further waives, with respect to any shares of Class
A Common Stock held by it or him, if any, any redemption rights it or he or she 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 (i) to approve
such Business Combination or in the context of a tender offer made by the Company to purchase shares of Class A Common Stock (although
the Sponsor, the Foundation the Insiders and their respective affiliates shall be entitled to redemption and liquidation rights
with respect to any shares of Class A Common Stock it or they hold if the Company fails to consummate a Business Combination within
24 months from the date of the closing of the Public Offering) or (ii) to approve an amendment to the Company’s amended and
restated certificate of incorporation to modify the substance or timing of its obligation to redeem 100% of our public shares if
we have not consummated a Business Combination within 24 months (or 27 months, if applicable) from the closing of the initial public
offering or with respect to any other material provisions relating to stockholders’ rights or pre- Business Combination activity.


 






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3.               The undersigned acknowledges and agrees that prior to entering into a definitive agreement for a Business Combination with
a target company 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.               During the period commencing on the effective date of the Underwriting Agreement and ending 180 days after such date, the
Sponsor, the Foundation and each Insider shall not, without the prior written consent of the Underwriter, Transfer any SAILSM
securities, shares of Class A Common Stock, Alignment Shares, Warrants or any securities
convertible into, or exercisable, or exchangeable for, shares of Class A Common Stock owned by it or him. The provisions of this
paragraph will not apply if the release or waiver is effected solely to permit a transfer not for consideration and 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.


 


5.               In the event of the liquidation of the Trust Account the Sponsor (which for purposes
of clarification shall not extend to any other shareholders, members or managers of the Sponsor, or any of the other undersigned)
(the “Indemnitor”) 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) 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 (except for the Company’s
independent auditors) or (ii) any prospective target business with which the Company has discussed entering into a transaction
agreement (a “Target”); provided, however, that such indemnification of the Company
by the Indemnitor (x) shall apply only to the extent necessary to ensure that such claims by a third party for services rendered
or products sold to the Company or a Target do not reduce the amount of funds in the Trust Account to below the lesser of (i) $10.00
per Public Share and (ii) the actual amount per Public Share held in the Trust Account as of the date of the liquidation of
the Trust Account if less than $10.00 per Public Share due to reductions in the value of the trust assets, in each case net of
the amount of interest earned on the property in the Trust Account which may be withdrawn to pay franchise and income taxes, except
as to any claims by a third party (including a Target) who executed a waiver of any and all rights to seek access to the Trust
Account and except as to any claims under the Company’s indemnity of the Underwriter against certain liabilities, including
liabilities under the Securities Act of 1933, as amended (the “Securities Act”). In the event that any
such executed waiver is deemed to be unenforceable against such third party, the Sponsor shall not be responsible to the extent
of any liability for such third party claims. 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.


 






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6.           To the extent that the Underwriter does not exercise its option to purchase the additional
SAILSM securities within 45 days from the date of the Prospectus in full
(as further described in the Prospectus), the Sponsor and the Foundation agree to automatically surrender to the Company for no
consideration, for cancellation at no cost, an aggregate number of Alignment Shares, on a pro rata basis, so that the number of
Alignment Shares will equal of 5% of the sum of the total number of shares of Class A Common Stock outstanding at such time. The
Sponsor, the Foundation and Insiders further agree that to the extent that the size of the Public Offering is increased or decreased,
the Company will effect a share capitalization or a share repurchase, as applicable, with respect to the Alignment Shares immediately
prior to the consummation of the Public Offering in such amount as to maintain the number of Alignment Shares at 5% of the sum
of the total number of shares of Class A Common Stock to be outstanding immediately after the consummation of the Public Offering.


 


7.           (a)      In order to minimize potential conflicts of interest that may arise from multiple corporate affiliations, the Insiders
hereby agree that until the earliest of the Company’s initial Business Combination or liquidation, the Insiders shall present
to the Company for its consideration, prior to presentation to any other entity, any target candidate that has a fair market value
of at least 80% of the net 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.


 


(b)     [Reserved].


 


(c)     The
Sponsor, the Foundation and each Insider hereby agrees and acknowledges that: (i) the Underwriter and the Company would be
irreparably injured in the event of a breach by such Sponsor, the Foundation or an Insider of its, his or her obligations under
paragraphs 1, 2, 3, 4, 5, 6, 7(a), 8(a), 8(b), 8(c) and 10, 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.


 


8.           (a)      The Sponsor, the Foundation and each Insider agrees that it, he or she shall not Transfer any Alignment
Shares (or shares of Class A Common Stock issuable upon conversion thereof) until the earlier of (x) 180 days after the
completion of 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 Class A Common Stock for cash, securities or other property (the “Alignment
Shares Lock-up Period”).


 


(b)    Reserved.


 


(c)    The Sponsor, the Foundation and each Insider agrees that it, he or she shall not Transfer any Private Placement Warrants
(and any shares of Class A Common Stock issued upon conversion or exercise thereof), until 30 days after the completion of the
Company’s initial Business Combination (the “Private Placement Lock-up Period”, and together with
the Performance Shares Lock-up Period and the Alignment Shares Lock-Up Period the
 “Lock-up Periods”).


 






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(d)     Notwithstanding the provisions set forth in paragraphs 8(a), (b) and (c), Transfers of the Alignment
Shares and Private Placement Warrants (and shares of Class A Common Stock issued or issuable upon the exercise or conversion
of the Private Placement Warrants and the Alignment Shares and that are held by the
Sponsor, the Foundation any Insider or any of their permitted transferees (that have complied with this paragraph 8(d)), 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 member of the Initial Stockholders, any affiliates or family members of any member of the Initial Stockholders, any members
or partners of the Company’s initial, or their affiliates, any affiliates of the Initial Stockholders, or any employees of
such affiliates; (b) in the case of an individual, by gift to a member of one of the individual’s immediate family or
to a trust, the beneficiary of which is a member of the individual’s immediate family, an affiliate of such person or to
a charitable organization; (c) in the case of an individual, by virtue of laws of descent and distribution upon death of the
individual; (d) in the case of an individual, pursuant to a qualified domestic relations order; (e) by private sales
or transfers made in connection with the consummation of an initial Business Combination at prices no greater than the price at
which the private placement warrants or shares of Class A common stock, as applicable, were originally purchased; (f) by
virtue of the Initial Stockholders’ organizational documents upon liquidation or dissolution of the Initial Stockholders;
(g) to the Company for no value for cancellation in connection with the consummation of the Company’s initial Business
Combination; (h) in the event of the Company’s liquidation prior to the completion of the Company’s initial Business
Combination; or (i) in the event of the Company’s completion of a liquidation, merger, share exchange 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 Company’s completion of the an initial Business Combination;
provided, however, that in the case of clauses (a) through (e) these permitted transferees must enter into a written agreement
agreeing to be bound by the restrictions herein.


 


9.            Each of the Insiders agrees to be a director or officer of the Company, as applicable, until the earlier of the consummation
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 an Insider as a director or officer (as applicable), each Insider agrees that he
or she will not, prior to the consummation 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 target candidate of the Company that is not generally known by persons
outside of the Company, the Sponsor, or their respective affiliates. The Sponsor, the Foundation and each Insider represents and
warrants that it, 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. 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 and contains all of the information required to
be disclosed pursuant to Item 401 of Regulation S-K, promulgated under the Securities Act. Each Insider’s questionnaire furnished
to the Company and the Underwriter is true and accurate in all material respects. Each Insider represents and warrants that: it,
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; it or he or she 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 it or he or she is not currently
a defendant in any such criminal proceeding.


 






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10.          Except as disclosed in the Prospectus, neither the Sponsor, the Foundation nor any Insider nor any affiliate of the Sponsor,
the Foundation or any Insider, nor any director or officer of the Company, 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 up to an aggregate of $300,000 made
to the Company by the Sponsor; payment to an affiliate of the Sponsor for office space, utilities and secretarial and administrative
support for a total of $10,000 per month; interest earned on the funds held in the trust account may be released to the Company
to pay its franchise and income tax obligations; 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 any of the Company’s officers or 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 Private Placement Warrants at a price of $1.50 per Private Placement Warrant at the option of the lender.


 


11.          The Sponsor, the Foundation and each Insider has full right and power, without violating any agreement to which it 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 a director on the board of directors of the Company and hereby consents
to being named in the Prospectus as a director of the Company.


 


12.          As used herein, (i) “Business Combination” shall mean
a merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses
or entities; (ii) “Capital Stock” shall mean, collectively, the Class A Common Stock and
the Alignment Shares; (iii) “Alignment Shares” shall mean the 2,587,500 and 287,500 shares of the
Company’s Class B common stock, par value $0.0001 per share, held by the Initial Stockholders, respectively (up to 375,000
shares of which are subject to complete or partial forfeiture by the Sponsor and Foundation on a pro rata basis if the over-allotment
option is not exercised by the Underwriter), for an aggregate purchase price of $25,000, or approximately $0.01 per share, prior
to the consummation of the Public Offering; (iv) “Initial Stockholders” shall mean the Sponsor,
Foundation and any Insider that holds Alignment Shares; (v) “Private Placement Warrants” shall mean
the warrants to purchase shares of Class A Common Stock of the Company that will be acquired by the Sponsor for an aggregate purchase
price of $18,500,000 (or $17,000,000 if the over-allotment option is not exercised by the Underwriter) or $1.50 per Private Placement
Warrant, in a private placement that shall close simultaneously with the consummation of the Public Offering (including Class A
Common Stock issuable upon conversion thereof); (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 certain of the proceeds from the sale of the Private Placement Warrants
shall be deposited; and (viii) “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 Securities Exchange Act of 1934, as amended, 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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13.          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.


 


14.          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 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. This Letter Agreement shall be binding
on the Sponsor, the Foundation and each Insider and their respective successors, heirs and assigns and permitted transferees.


 


15.          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.


 


16.          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.


 


17.          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 further that paragraph 5 of this Letter Agreement shall survive such liquidation.


 


18.          The Sponsor hereby consents to the issuance of shares of Class A Common Stock pursuant to the Underwriting Agreement. pursuant to
the terms of the shares of Class B Common Stock, pursuant to the terms of the Warrant Agreement, dated November 12, 2020, by and between
the Company and Continental Stock Transfer and Trust Company, and consents to any distributions made in connection with any redemption
rights set forth in the Company’s amended and restated certificate of incorporation.


 


[Signature Page Follows]


 






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	 	Sincerely,



	 	 	 	 
	 	HAAC SPONSOR, LLC



	 	 	 	 
	 	By:	/s/ Evan Sotiriou
	 	 	Name:	Evan Sotiriou
	 	 	Title:	Chief Operating Officer
	 	 	 	 
	 	HEALTH ASSURANCE ECONOMY FOUNDATION



	 	 	 	 
	 	By:	/s/ Chris McCain
	 	 	Name:	Chris McCain
	 	 	Title:	Chief Legal Officer
	 	 	 	 
	 	By:	/s/ Hemant Taneja
	 	 	Hemant Taneja



	 	 	 	 
	 	By:	/s/ Quentin Clark
	 	 	Quentin Clark
	 	 	 	 
	 	By:	/s/ Stephen K. Klasko
	 	 	Stephen K. Klasko
	 	 	 	 
	 	By:	/s/ Anita Pramoda
	 	 	Anita Pramoda
	 	 	 	 
	 	By:	/s/ Jennifer Schneider, MD
	 	 	Jennifer Schneider, MD
	 	 	 	 
	 	By:	/s/ Glen Tullman
	 	 	Glen Tullman



	 	 	 	 
	 	By:	/s/ Evan Sotiriou
	 	 	Evan Sotiriou






 


[Signature Page to Letter Agreement]


 



    	 	 	 



     


    




 





	Acknowledged and Agreed:	 
	 	 	 
	HEALTH ASSURANCE ACQUISITION CORP.	 
	 	 	 
	By:	/s/ Evan Sotiriou	 
	Name:	Evan Sotiriou	 
	Title:	Chief Operating Officer	 



 


[Signature Page to Letter Agreement]