EXHIBIT
4.4


 


DESCRIPTION
OF OUR SECURITIES


 


The
following summary of the material terms of our securities is not intended to be a complete summary of the rights and preferences
of such securities, and is qualified by reference to our Second Amended and Restated Certificate
of Incorporation (the “Certificate of Incorporation”),
our Bylaws and the Warrant-related documents described herein, which are exhibits to the registration statement on
Form S-1 filed with the SEC on November 23, 2020 (File Number 333-249649).
We urge you to read each of our Certificate of Incorporation, the Bylaws and the Warrant-related documents described herein
in their entirety for a complete description of the rights and preferences of our securities.


 


On October 1, 2020 (the “Closing
Date”), Tortoise Acquisition Corp., our predecessor company, consummated the previously announced merger pursuant to that
certain Business Combination Agreement, dated June 18, 2020 (the “Business Combination Agreement”), by and among
the TortoiseCorp, SHLL Merger Sub Inc., a Delaware corporation and wholly owned subsidiary of TortoiseCorp (“Merger Sub”),
and Hyliion Inc., a Delaware corporation (“Legacy Hyliion”). Pursuant to the terms of the Business Combination Agreement,
a business combination between the Company and Legacy Hyliion was effected through the merger of Merger Sub with and into Legacy
Hyliion, with Legacy Hyliion surviving as the surviving company and as a wholly-owned subsidiary of TortoiseCorp (the “Merger”
and, collectively with the other transactions described in the Business Combination Agreement, the “Business Combination”).
On the Closing Date, and in connection with the closing of the Business Combination (the “Closing”), Tortoise Acquisition
Corp. changed its name to Hyliion Holdings Corp. Unless the context indicates otherwise, references in this document to the “Company,”
“Hyliion,” “we,” “us,” “our” and similar terms refer to Hyliion Holdings Corp.
(f/k/a Tortoise Acquisition Corp.) and its consolidated subsidiaries (including Legacy Hyliion). References to “TortoiseCorp”
refer to our predecessor company prior to the consummation of the Business Combination. Terms not otherwise defined in this document
are defined in the Company’s Form S-1 filed with the SEC on November 23, 2020 (File Number 333-249649).


 


Authorized
and Outstanding Stock


 


Our Certificate of Incorporation authorizes
the issuance of 250,000,000 shares of Common Stock, $0.0001 par value per share, and 10,000,000 shares of preferred stock,
$0.0001 par value per share. As of February 23, 2021, there were approximately 170,255,200 shares of Common Stock and no shares
of preferred stock outstanding. The outstanding shares of Common Stock are duly authorized, validly issued, fully paid and non-assessable.


 


Common
Stock


 


Voting
Power


 


Except
as otherwise required by law or as otherwise provided in any certificate of designation for any series of preferred stock, the
holders of Common Stock will possess all voting power for the election of our directors and all other matters requiring stockholder
action. Holders of Common Stock will be entitled to one vote per share on matters to be voted on by stockholders.


 


Dividends


 


Holders
of Common Stock will be entitled dividends, if any, as may be declared from time to time by the Board in its discretion. Such
dividends may be paid in cash, in property, or in shares of the capital stock, subject to the provisions of our Certificate of
Incorporation and applicable law. We may retain future earnings, if any, for future operations, expansion and debt repayment and
have no current plans to pay cash dividends for the foreseeable future. Any decision to declare and pay dividends in the future
will be made at the discretion of the Board and will depend on, among other things, our results of operations, financial condition,
cash requirements, contractual restrictions and other factors that the Board may deem relevant. In addition, our ability to pay
dividends may be limited by covenants of any existing and future outstanding indebtedness we or our subsidiaries incur.


 


Preemptive
or Other Rights


 


Holders
of Common Stock have no conversion, preemptive or other subscription rights and there will be no sinking fund or redemption provisions
applicable to the Common Stock.


 


Election
of Directors


 


The
Board is divided into three classes, each of which will serve for a term of three years with only one class of directors being
elected in each year. There is no cumulative voting with respect to the election of directors, with the result that the holders
of more than 50% of the shares voted for the election of directors can elect all of the directors.


 


Preferred
Stock


 


Our
Certificate of Incorporation provides that shares of preferred stock may be issued from time to time in one or more series. The
Board is authorized to fix the voting rights, if any, designations, powers, preferences, the relative, participating, optional
or other special rights and any qualifications, limitations and restrictions thereof, applicable to the shares of each series.
The Board will be able to, without stockholder approval, issue preferred stock with voting and other rights that could adversely
affect the voting power and other rights of the holders of the Common Stock and could have anti-takeover effects. The ability
of the Board to issue preferred stock without stockholder approval could have the effect of delaying, deferring or preventing
a change of control of Hyliion or the removal of the management.


 






     


     


    

 


Warrants


 


As of December 31, 2020, all outstanding warrants were either
exercised or redeemed.


 


Lock-Up
Restrictions


 


Certain of our stockholders are subject to
certain restrictions on transfer until the termination of applicable lock-up periods.


 


Certain
Anti-Takeover Provisions of Delaware Law


 


Special
Meetings of Stockholders


 


Our
Certificate of Incorporation provides that special meetings of our stockholders may be called by such persons as provided in the
Bylaws. The Bylaws provide that special meetings of our stockholders may be called only, for any purpose as is a proper matter
for stockholder action under Delaware, by (i) our Chairperson of the Board of Directors, (ii) our Chief Executive Officer
or the President if the Chairperson of the Board of Directors is unavailable, or (iii) the Board of Directors pursuant to
a resolution adopted by a majority of the total number of authorized directors (whether or not there exist any vacancies in previously
authorized directorships at the time any such resolution is presented to the Board of Directors for adoption).


 


Advance
Notice Requirements for Stockholder Proposals and Director Nominations


 


Our
Bylaws provide that stockholders seeking to bring business before our annual meeting of stockholders, or to nominate candidates
for election as directors at our annual meeting of stockholders, must provide timely notice of their intent in writing. To be
timely under the Bylaws, a stockholder’s notice will need to be received by the company secretary at our principal executive
offices not later than the close of business on the 90th day nor earlier than the open of business on the 120th day prior to the
first anniversary of the preceding year’s annual meeting of stockholders; provided, however, that in the event that no annual
meeting was held in the previous year or the annual meeting is called for a date that is more than 30 days before or after
the anniversary date of the previous year’s annual meeting, notice by the stockholder must be received by the secretary
no earlier than the close of business on the 120th day prior to such annual meeting and no later than the close of business on
the latter of the 90th day prior to such annual meeting or the 10th day following the day on which public announcement of the
date of such meeting is first made. Our Certificate of Incorporation and the Bylaws specify certain requirements as to the form
and content of a stockholders’ meeting. These provisions may preclude our stockholders from bringing matters before our
annual meeting of stockholders or from making nominations for directors at our annual meeting of stockholders.


 


Authorized
but Unissued Shares


 


Our
authorized but unissued Common Stock and preferred stock are available for future issuances without stockholder approval and could
be utilized for a variety of corporate purposes, including future offerings to raise additional capital, acquisitions and employee
benefit plans. The existence of authorized but unissued and unreserved Common Stock and preferred stock could render more difficult
or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.


 


Exclusive
Forum Selection


 


Our
Certificate of Incorporation requires, to the fullest extent permitted by law, that derivative actions brought in our name, actions
against current or former directors, officers and employees for breach of fiduciary duty, other similar actions, any other action
as to which the DGCL confers jurisdiction to the Court of Chancery of the State of Delaware and any action or proceeding concerning
the validity of our Certificate of Incorporation or the Bylaws may be brought only in the Court of Chancery in the State of Delaware
(or, if and only if the Court of Chancery of the State of Delaware does not have subject matter jurisdiction thereof, any state
court located in the State of Delaware or, if and only if all such state courts lack subject matter jurisdiction, the federal
district court for the District of Delaware). Although we believe this provision benefits us by providing increased consistency
in the application of Delaware law in the types of lawsuits to which it applies, the provision may limit a stockholder’s
ability to bring a claim in a judicial forum that it finds favorable for disputes with us and our directors, officers or other
employees and may have the effect of discouraging lawsuits against our directors and officers. This provision would not apply
to claims brought to enforce a duty or liability created by the Exchange Act or any other claim for which the federal courts have
exclusive jurisdiction. To the extent that any such claims may be based upon federal law claims, Section 27 of the Exchange
Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act
or the rules and regulations thereunder. Furthermore, Section 22 of the Securities Act creates concurrent jurisdiction for
federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and
regulations thereunder. However, our Certificate of Incorporation provides that the federal district courts of the United States
shall be the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act.
Stockholders may be subject to increased costs to bring these claims, and the exclusive forum provision could have the effect
of discouraging claims or limiting investors’ ability to bring claims in a judicial forum that they find favorable. In addition,
the enforceability of similar exclusive forum provisions in other companies’ certificates of incorporation has been challenged
in legal proceedings, and it is possible that, in connection with one or more actions or proceedings described above, a court
could rule that this provision in our Certificate of Incorporation is inapplicable or unenforceable.


 






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Section 203
of the Delaware General Corporation Law


 


We
do not opt out of Section 203 of the DGCL under our Certificate of Incorporation.


 


Limitation
on Liability and Indemnification of Directors and Officers


 


Our
Certificate of Incorporation eliminates our directors’ liability to the fullest extent permitted under the DGCL. The DGCL
provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties
as directors, except for liability:


 


		●	for
any transaction from which the director derives an improper personal benefit;



 


		●	for
any act or omission not in good faith or that involves intentional misconduct or a knowing violation of law;



 


		●	for
any unlawful payment of dividends or redemption of shares; or



 


		●	for
any breach of a director’s duty of loyalty to the corporation or its stockholders.



 


If
the DGCL is amended to authorize corporate action further eliminating or limiting the personal liability of directors, then the
liability of the Company’s directors will be eliminated or limited to the fullest extent permitted by the DGCL, as so amended.


 


Delaware
law and our Certificate of Incorporation and Bylaws provide that the Company will, in certain situations, indemnify its directors
and officers and may indemnify other employees and other agents, to the fullest extent permitted by law. Any indemnified person
is also entitled, subject to certain limitations, to advancement of reasonable expenses (including attorneys’ fees and disbursements)
in advance of the final disposition of the proceeding.


 


In
addition, we have entered into separate indemnification agreements with our directors and officers. These agreements, among other
things, require us to indemnify our directors and officers for certain expenses, including attorneys’ fees, judgments, fines,
and settlement amounts incurred by a director or officer in any action or proceeding arising out of their services as one of our
directors or officers or any other company or enterprise to which the person provides services at our request.


 


We
maintain a directors’ and officers’ insurance policy pursuant to which our directors and officers are insured against
liability for actions taken in their capacities as directors and officers. We believe these provisions in our Certificate of Incorporation
and the Bylaws and these indemnification agreements are necessary to attract and retain qualified persons as directors and officers.


 


Insofar
as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers, or control persons,
in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.


 






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Rule 144


 


Rule 144
is not available for the resale of securities initially issued by shell companies (other than business combination related shell
companies) or issuers that have been at any time previously a shell company, such as the Company. However, Rule 144 also
includes an important exception to this prohibition if the following conditions are met:


 


		●	the
issuer of the securities that was formerly a shell company has ceased to be a shell company;



 


		●	the
issuer of the securities is subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act;



 


		●	the
issuer of the securities has filed all Exchange Act reports and material required to be filed, as applicable, during the preceding
12 months (or such shorter period that the issuer was required to file such reports and materials), other than Form 8-K reports;
and



 


		●	at
least one year has elapsed from the time that the issuer filed current Form 10 type information with the SEC reflecting its
status as an entity that is not a shell company.



 


Upon
the Closing, the Company ceased to be a shell company.


 


When
and if Rule 144 becomes available for the resale of our securities, a person who has beneficially owned restricted shares
of our Common Stock or Warrants for at least six months would be entitled to sell their securities, provided that (i) such
person is not deemed to have been one of our affiliates at the time of, or at any time during the three months preceding, a sale
and (ii) we are subject to the Exchange Act periodic reporting requirements for at least three months before the sale and
have filed all required reports under Section 13 or 15(d) of the Exchange Act during the 12 months (or such shorter
period as we were required to file reports) preceding the sale.


 


Persons
who have beneficially owned restricted shares of our Common Stock or Warrants for at least six months but who are our affiliates
at the time of, or at any time during the three months preceding, a sale, would be subject to additional restrictions, by which
such person would be entitled to sell within any three-month period only a number of securities that does not exceed the
greater of:


 


		●	one
percent (1%) of the total number of shares of Common Stock then outstanding; or



 


		●	the
average weekly reported trading volume of the Common Stock during the four calendar weeks preceding the filing of a notice on
Form 144 with respect to the sale.



 


Sales
by our affiliates under Rule 144 will also be limited by manner of sale provisions and notice requirements and to the availability
of current public information about us.


 


Transfer
Agent, Warrant Agent and Registrar


 


The
transfer agent, Warrant Agent and registrar for our Common Stock and Warrants is Continental Stock Transfer & Trust Company.


 


Listing
of Securities


 


Our Common Stock is listed on the NYSE under
the symbol “HYLN”


 


 


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