Exhibit 4.5


 


DESCRIPTION OF EACH CLASS OF SECURITIES 


REGISTERED UNDER SECTION 12 OF THE EXCHANGE
ACT


 


As of December 31, 2020, Biotech Acquisition Company (“we,”
“our,” “us” or the “Company”) had no securities registered under Section 12 of the Securities
Exchange Act of 1934, as amended (the “Exchange Act”). As of January 25, 2021, we had the following three classes of
securities registered under Section 12 of the Exchange Act: (i) units, consisting of one share of our Class A ordinary shares (as
defined below) and one-half of one redeemable warrant (as defined below), with each whole warrant entitling the holder thereof
to purchase one Class A ordinary share at a price of $11.50 per share; (ii) Class A ordinary shares, $0.0001 par value per share
(our “Class A ordinary shares”); and (iii) our public warrants, with each whole warrant exercisable for one share of
Class A ordinary shares for $11.50 per share (the “warrants”).


Pursuant to our amended and restated memorandum
and articles of association, we are authorized to issue 500,000,000 Class A ordinary shares, $0.0001 par value each, 50,000,000
Class B ordinary shares, $0.0001 par value each, and 5,000,000 undesignated preferred shares, $0.0001 par value each. The following
description summarizes the material terms of our shares, as set out more particularly in our amended and restated memorandum and
articles of association, a copy of which is a separate exhibit to the Annual Report on Form 10-K to which this Exhibit 4.5 is appended
(such Annual Report, the “Report”), and the material terms of our warrants, as set out more particularly in the warrant
agreement dated January 25, 2021 between us and Continental Stock Transfer & Trust Company, as warrant agent, a copy of which
is a separate exhibit to the Report. This summary is qualified in its entirety by the terms and conditions set forth in such separate
exhibits.


Units


 


Each unit consists of one Class A ordinary share and one-half of
one redeemable warrant. Each whole warrant entitles the holder thereof to purchase one Class A ordinary share at a price of $11.50
per share, subject to adjustment as described in the warrant agreement. Pursuant to the warrant agreement, a warrant holder may
exercise its warrants only for a whole number of the company’s Class A ordinary shares.


 


Ordinary Shares 


Class A ordinary shareholders and Class B ordinary shareholders
of record are entitled to one vote for each share held on all matters to be voted on by shareholders, and vote together as a single
class, except as may otherwise be required by law. Unless specified otherwise in the Companies Law (2020 Revision) of the Cayman
Islands (the “Companies Law”), our amended and restated memorandum and articles of association or applicable stock
exchange rules, the affirmative vote of a majority of our ordinary shares that are voted is required to approve any such matter
voted on by our shareholders. Approval of certain actions would require a special resolution under Cayman Islands law and pursuant
to our amended and restated memorandum and articles of association; such actions include amending our amended and restated memorandum
and articles of association and approving a statutory merger or consolidation with another company. There is no cumulative voting
with respect to the appointment of directors. Our shareholders are entitled to receive dividends when, as and if declared by the
board of directors out of funds legally available therefor.


We will provide our public shareholders with the opportunity
to redeem all or a portion of their public shares upon the completion of our initial business combination at a per-share price,
payable in cash, equal to the aggregate amount then on deposit in the trust account calculated as of two business days prior to
the consummation of our initial business combination, including interest (which interest shall be net of taxes payable), divided
by the number of then issued and outstanding public shares, subject to the limitations described herein. The per-share amount
we will distribute to investors who properly redeem their shares will not be reduced by the deferred underwriting commissions we
will pay to the underwriters. The redemption rights will include the requirement that a beneficial owner must identify itself in
order to validly redeem its shares. Our initial shareholders, directors and officers have entered into a letter agreement with
us, pursuant to which they have agreed to waive their redemption rights with respect to any founder shares and public shares held
by them in connection with the completion of our initial business combination or certain amendments to our amended and restated
memorandum and articles of association. A copy of this letter agreement is a separate exhibit to the Report. Permitted transferees
of our initial shareholders, directors or officers will be subject to the same obligations.






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If we seek shareholder approval of our initial business combination
and we do not conduct redemptions in connection with our initial business combination pursuant to the tender offer rules, our amended
and restated memorandum and articles of association provide that a public shareholder, together with any affiliate of such shareholder
or any other person with whom such shareholder is acting in concert or as a “group” (as defined under Section 13
of the Exchange Act), will be restricted from redeeming its shares with respect to more than an aggregate of 15% of the ordinary
shares sold in our initial public offering, which we refer to as the “Excess Shares,” without our prior consent. However,
we would not be restricting our shareholders’ ability to vote all of their shares (including Excess Shares) for or against
our initial business combination. Our shareholders’ inability to redeem the Excess Shares will reduce their influence over
our ability to complete our initial business combination, and such shareholders could suffer a material loss in their investment
if they sell such Excess Shares on the open market. Additionally, such shareholders will not receive redemption distributions with
respect to the Excess Shares if we complete the business combination. As a result, such shareholders will continue to hold that
number of shares exceeding 15% and, in order to dispose such shares would be required to sell their shares in open market transactions,
potentially at a loss.


In the event of a liquidation, dissolution or winding up of
the company after a business combination, our shareholders at such time will be entitled to share ratably in all assets remaining
available for distribution to them after payment of liabilities and after provision is made for each class of shares, if any, having
preference over the ordinary shares. Our shareholders have no preemptive or other subscription rights.


There are no sinking fund provisions applicable to the ordinary
shares, except that we will provide our shareholders with the opportunity to redeem their public shares for cash equal to their
pro rata share of the aggregate amount then on deposit in the trust account, including interest (which interest shall be net of
taxes payable), upon the completion of our initial business combination, subject to the limitations described herein.


Redeemable Warrants


Each whole warrant entitles
the registered holder to purchase one Class A ordinary share at a price of $11.50 per share, subject to adjustment as discussed
below, at any time commencing on the later of 30 days after the completion of our initial business combination and 12 months
from the closing of our initial public offering, except as described below. Pursuant to the warrant agreement, a warrant holder
may exercise its warrants only for a whole number of Class A ordinary shares. The warrants will expire five years after the completion
of our initial business combination, at 5:00 p.m., New York City time, or earlier upon redemption or liquidation.


We will not be obligated to deliver any Class A ordinary shares
pursuant to the exercise of a warrant and will have no obligation to settle such warrant exercise unless a registration statement
under the Securities Act of 1933, as amended (the “Securities Act”), covering the issuance of the Class A ordinary
shares issuable upon exercise of the warrants is then effective and a current prospectus relating thereto is available, subject
to our satisfying our obligations described below with respect to registration, or a valid ex emption from registration is available,
including in connection with a cashless exercise. No warrant will be exercisable for cash or on a cashless basis, and we will not
be obligated to issue any shares to holders seeking to exercise their warrants, unless the issuance of the shares upon such exercise
is registered or qualified under the securities laws of the state of the exercising holder, or an exemption is available. In the
event that the conditions in the two immediately preceding sentences are not satisfied with respect to a warrant, the holder of
such warrant will not be entitled to exercise such warrant and such warrant may have no value and expire worthless. In the event
that a registration statement is not effective for the exercised warrants, the purchaser of a unit containing such warrant will
have paid the full purchase price for the unit solely for the Class A ordinary share underlying such unit.


We have not registered the Class A ordinary shares issuable
upon exercise of the warrants at this time. However, we have agreed that as soon as practicable, but in no event later than 15
business days, after the closing of our initial business combination, we will use our commercially reasonable efforts to file with
the SEC a registration statement covering the issuance, under the Securities Act, of the Class A ordinary shares issuable upon
exercise of the warrants, and we will use our commercially reasonable efforts to cause the same to become effective within 60 business
days after the closing of our initial business combination and to maintain the effectiveness of such registration statement, and
a current prospectus relating thereto, until the expiration of the warrants in accordance with the provisions of the warrant agreement.
Notwithstanding the above, if our Class A ordinary shares are, at the time of any exercise of a warrant, not listed on a national
securities exchange such that they satisfy the definition of a “covered security” under Section 18(b)(1) of the
Securities Act, we may, at our option, require holders of public warrants who exercise their warrants to do so on a “cashless
basis” in accordance with Section 3(a)(9) of the Securities Act and, in the event we so elect, we will not be required
to file or maintain in effect a registration statement, but will use our commercially reasonable efforts to register or qualify
the shares under applicable blue sky laws to the extent an exemption is not available. In such event, each holder would pay the
exercise price by surrendering the warrants for that number of Class A ordinary shares equal to the quotient obtained by dividing
(x) the product of the number of Class A ordinary shares underlying the warrants, multiplied by the excess of the “fair
market value” (as defined below) less the exercise price of the warrants by (y) the fair market value. The “fair market
value” shall mean the volume weighted average price of the Class A ordinary shares for the 10 trading days ending on the
trading day prior to the date on which the notice of exercise is received by the warrant agent.






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Redemption of warrants. Once the warrants
become exercisable, we may redeem the outstanding warrants (except as described herein with respect to the private placement warrants):


•        in
whole and not in part;


•        at
a price of $0.01 per warrant;


•        upon
not less than 30 days’ prior written notice of redemption to each warrant holder; and


•        if,
and only if, the last reported sale price of the Class A ordinary shares for any 20 trading days within a 30-trading day
period ending on the third trading day prior to the date on which we send the notice of redemption to the warrant holders (which
we refer to as the “Reference Value”) equals or exceeds $18.00 per share (as adjusted for share sub-divisions, share
dividends, rights issuances, consolidations, reorganizations, recapitalizations and the like).


We will not redeem the warrants
as described above unless a registration statement under the Securities Act covering the issuance of the Class A ordinary shares
issuable upon exercise of the warrants is then effective and a current prospectus relating to those Class A ordinary shares is
available throughout the 30-day redemption period. If and when the warrants become redeemable
by us, we may exercise our redemption right even if we are unable to register or qualify the underlying securities for sale under
all applicable state securities laws.


If we call the warrants for redemption as described above,
our management will have the option to require any holder that wishes to exercise its warrant to do so on a “cashless basis.”
In determining whether to require all holders to exercise their warrants on a “cashless basis,” our management will
consider, among other factors, our cash position, the number of warrants that are outstanding and the dilutive effect on our shareholders
of issuing the maximum number of Class A ordinary shares issuable upon the exercise of our warrants. If our management takes advantage
of this option, all holders of warrants would pay the exercise price by surrendering their warrants for that number of Class A
ordinary shares equal to the quotient obtained by dividing (x) the product of the number of Class A ordinary shares underlying
the warrants, multiplied by the excess of the “fair market value” over the exercise price of the warrants by (y) the
fair market value. The “fair market value” shall mean the average last reported sale price of the Class A ordinary
shares for the 10 trading days ending on the third trading day prior to the date on which the notice of redemption is sent to the
holders of warrants. If our management takes advantage of this option, the notice of redemption will contain the information necessary
to calculate the number of shares of Class A ordinary shares to be received upon exercise of the warrants, including the “fair
market value” in such case. Requiring a cashless exercise in this manner will reduce the number of shares to be issued and
thereby lessen the dilutive effect of a warrant redemption. We believe this feature is an attractive option to us if we do not
need the cash from the exercise of the warrants after our initial business combination. If we call our warrants for redemption
and our management does not take advantage of this option, our sponsor and its permitted transferees would still be entitled to
exercise their private placement warrants for cash or on a cashless basis using the same formula described above that other warrant
holders would have been required to use had all warrant holders been required to exercise their warrants on a cashless basis, as
described in more detail below.


Redemption procedures. A holder of a
warrant may notify us in writing in the event it elects to be subject to a requirement that such holder will not have the right
to exercise such warrant, to the extent that after giving effect to such exercise, such person (together with such person’s
affiliates), to the warrant agent’s actual knowledge, would beneficially own in excess of 9.8% (or such other amount as a
holder may specify) of the Class A ordinary shares issued and outstanding immediately after giving effect to such exercise.






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Anti-dilution adjustments. The warrants
have certain anti-dilution and adjustments rights upon certain events.


In addition, if (x) we issue
additional ordinary shares or equity-linked securities for capital raising purposes in
connection with the closing of our initial business combination at an issue price or effective issue price of less than $9.20 per
ordinary share (with such issue price or effective issue price to be determined in good faith by our board of directors and, in
the case of any such issuance to our sponsor or its affiliates, without taking into account any founder shares held by our sponsor
or such affiliates, as applicable, prior to such issuance) (the “Newly Issued Price”), (y) the aggregate gross proceeds
from such issuances represent more than 60% of the total equity proceeds, and interest thereon, available for the funding of our
initial business combination on the date of the completion of our initial business combination (net of redemptions), and (z) the
volume weighted average trading price of our Class A ordinary shares during the 20 trading day period starting on the trading day
prior to the day on which we consummate our initial business combination (such price, the “Market Value”) is below
$9.20 per share, the exercise price of the warrants will be adjusted (to the nearest cent) to be equal to 115% of the higher of
the Market Value and the Newly Issued Price, and the $18.00 per share redemption trigger price described above will be adjusted
(to the nearest cent) to be equal to 180% of the higher of the Market Value and the Newly Issued Price.


The warrants will be issued
in registered form under a warrant agreement between Continental Stock Transfer & Trust Company, as warrant agent, and us.
The warrant agreement provides that the terms of the warrants may be amended without the consent of any holder for the purpose
of (i) curing any ambiguity or correct any mistake, including to conform the provisions of the warrant agreement to the description
of the terms of the warrants and the warrant agreement set forth in the Report, or defective provision or (ii) adding or changing
any provisions with respect to matters or questions arising under the warrant agreement as the parties to the warrant agreement
may deem necessary or desirable and that the parties deem to not adversely affect the rights of the registered holders of the warrants,
provided that the approval by the holders of at least a majority of the then-outstanding public
warrants is required to make any change that adversely affects the interests of the registered holders. You should review a copy
of the warrant agreement, which has been filed as an exhibit to the registration statement in connection with our initial public
offering, for a complete description of the terms and conditions applicable to the warrants. 


The warrant holders do not have the rights or privileges of
holders of ordinary shares and any voting rights until they exercise their warrants and receive Class A ordinary shares. After
the issuance of Class A ordinary shares upon exercise of the warrants, each holder will be entitled to one vote for each share
held of record on all matters to be voted on by shareholders.


No fractional warrants will be issued upon separation of the
units and only whole warrants will trade.


 


 


 



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