Exhibit 2.3

DESCRIPTION OF SECURITIES

The following
description is a summary of certain information relating to the share capital of Materialise NV, certain provisions of the restated articles of association of Materialise NV, or our articles of association, the Belgian Company Code and the deposit
agreement governing the American Depositary Shares, or ADSs, each representing one ordinary share. For the purposes of the following description, except as otherwise required by the context, references to Materialise,
Company, we, us and our are to Materialise NV, and you refers to holders of the ADSs. Because this description is a summary, it may not contain all information which is important to you.
Accordingly, this description is qualified entirely by reference to our articles of association, the deposit agreement and the form of ADR, copies of which have been publicly filed with the Securities and Exchange Commission, or the SEC.

The following description includes comparisons of certain provisions of our articles of association and the Belgian Company Code applicable to us and the
Delaware General Corporation Law, or the DGCL, the law under which many publicly listed companies in the United States are incorporated. Because such statements are summaries, they do not address all aspects of Belgian law that may be relevant to us
and our shareholders or all aspects of Delaware law which may differ from Belgian law, and are not intended to be a complete discussion of the respective rights.

Share Capital

Our share capital is represented by
registered ordinary shares with no nominal but par value of 0.058 (rounded). Our share capital is fully paid-up. There are no separate classes of shares. The respective number of our ordinary shares
issued and outstanding as of the last day of the fiscal year to which the annual report to which this description is attached or incorporated by reference as an exhibit pertains is given on the cover page of such annual report.

On June 30, 2014, we sold 8,000,000 ADSs in our initial public offering at a price of $12.00 per ADS. In connection with the closing of our initial
public offering, we converted our outstanding Class A ordinary shares, Class B ordinary shares and Class C ordinary shares into ordinary shares and effected a stock split of our outstanding ordinary shares, whereby each ordinary share
was converted into four ordinary shares.

Form and Transferability of Our Shares

All of our shares belong to the same class of securities and are in registered form.

All of our outstanding shares are fully paid-up and freely transferable, subject to any contractual restrictions.

Currency

All of our shares are denominated in
euro.

Changes to Our Share Capital

Changes
to our share capital are decided by our shareholders. Our shareholders may at any time at a shareholders meeting decide to increase or decrease our share capital. Such resolution must satisfy the quorum and majority requirements that apply to
an amendment of the articles of association, as described below in Description of the Rights and Benefits Attached To Our SharesRight to Attend and Vote at Our Shareholders MeetingsQuorum and Majority
Requirements. No shareholder is liable to make any further contribution to our share capital other than with respect to shares held by such shareholder that are not fully paid-up.

Share Capital Increases by Our Board of Directors



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Subject to the quorum and majority requirements described below in Description of the Rights and
Benefits Attached To Our SharesRight to Attend and Vote at Our Shareholders MeetingQuorum and Majority Requirements, our shareholders meeting may authorize our board of directors, within certain limits, to increase our
share capital without any further approval of our shareholders. A capital increase that is authorized in this manner is referred to as authorized capital. This authorization can only be granted for a renewable period of a maximum of five years and
may not exceed the amount of the registered share capital at the time of the authorization.

At our annual ordinary general shareholders meeting of
June 4, 2019, our shareholders authorized our board of directors, for a period of five years from the date of publication of the changes to the articles of association decided by our shareholders meeting on June 4, 2019, to increase our share
capital, in one or more transactions, up to a maximum amount equal to the amount of our share capital as of the date of the annual ordinary general shareholders meeting.

Preferential Subscription Rights

In the event of a share
capital increase for cash through the issuance of new shares, or in the event we issue convertible bonds or warrants, our existing shareholders have a preferential right to subscribe, pro rata, to the new shares, convertible bonds or warrants. These
preferential subscription rights are transferable during the subscription period. Our board of directors may decide that preferential subscription rights which were not exercised, or were only partly exercised, by any shareholders shall accrue
proportionally to the other shareholders who have already exercised their preferential subscription rights, and shall fix the practical terms for such subscription.

Our shareholders may, at a shareholders meeting, decide to limit or cancel this preferential subscription right, subject to special reporting
requirements. Such decision by the shareholders must satisfy the same quorum and majority requirements as the decision to increase our share capital. Shareholders may also decide to authorize our board of directors to limit or cancel the
preferential subscription right within the framework of the authorized capital, subject to the terms and conditions set forth in the Belgian Company Code. Our board of directors currently has the authority to increase the share capital within the
framework of the authorized capital, and the right to limit or cancel the preferential subscription right within the framework of the authorized capital. See also Share Capital Increases by Our Board of Directors above. Generally,
unless expressly authorized in advance by the shareholders meeting, the authorization of our board of directors to increase the share capital through contributions in cash with cancellation or limitation of the preferential subscription right
of the existing shareholders is suspended as of the notification to us by the Belgian Financial Services and Markets Authority, or the FSMA, of a public takeover bid for our securities.

Under the DGCL, stockholders of a Delaware corporation have no preemptive rights to subscribe for additional issues of stock or to any security convertible
into such stock unless, and to the extent that, such rights are expressly provided for in the corporations certificate of incorporation.

Purchases and Sales of Our Own Shares

We may only
repurchase our own shares pursuant to authorization of our shareholders at a shareholders meeting taken under the conditions of quorum and majority provided for in the Belgian Company Code. Pursuant to the Belgian Company Code, such a decision
requires a quorum of shareholders holding an aggregate of at least 50% of the share capital and approval by a majority of at least 80% of the share capital present or represented. If there is no quorum, a second meeting must be convened. No quorum
is required at the second meeting, but the relevant resolution must be approved by a majority of at least 80% of the share capital present or represented. Any offer by us to purchase our own shares must be made on the same terms and conditions to
all of our shareholders.

Under the DGCL, a Delaware corporation may purchase or redeem its own shares unless the capital of the corporation is impaired
or the purchase or redemption would cause an impairment of the capital of the corporation.



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Our board of directors is authorized to acquire our own shares if such acquisition is necessary to prevent
serious and imminent harm to us. This authorization is valid for three years from the date of the publication of the authorization in the Annexes to the Belgian State Gazette (Belgisch Staatsblad/Moniteur belge).

Our board of directors is also authorized to sell our own shares at a price that it determines. This authorization is valid without restriction in time. The
authorization is also valid for the sale of our shares by one of our direct subsidiaries, as defined in Article 627 of the Belgian Company Code.

Exchange Controls and Limitations Affecting Shareholders

There are no Belgian exchange control regulations that impose limitations on our ability to make, or the amount of, cash payments to residents of the United
States.

Belgian Legislation

Disclosure of
Significant Shareholdings

The Belgian Law of May 2, 2007 on the disclosure of significant shareholdings in issuers whose securities are
admitted to trading on a regulated market and containing various provisions does not apply to us. However, in accordance with U.S. federal securities laws, holders of our ordinary shares and holders of ADSs representing our ordinary shares will be
required to comply with disclosure requirements relating to their ownership of our securities. Any person who, after acquiring beneficial ownership of our ordinary shares or ADSs representing our ordinary shares, is the beneficial owners of more
than 5% of our outstanding ordinary shares or ordinary shares underlying ADSs must file with the Securities and Exchange Commission a Schedule 13D or Schedule 13G, as applicable, disclosing the information required by such schedules, including the
number of our ordinary shares or ordinary shares underlying ADSs that such person has acquired (whether alone or jointly with one or more other persons). In addition, if any material change occurs in the facts set forth in the report filed on
Schedule 13D (including a more than 1% increase or decrease in the percentage of the total shares beneficially owned), the beneficial owner must promptly file an amendment disclosing such change.

Public Takeover Bids

Public takeover bids in
Belgium for our shares or other securities giving access to voting rights are subject to supervision by the FSMA. Public takeover bids must be extended to all of the voting securities, as well as all other securities giving access to voting rights.
Prior to making a bid, a bidder must publish a prospectus which has been approved by the FSMA prior to publication.

However, the Belgian rules on
mandatory takeover bids, which provide that a mandatory bid must be launched if a person, as a result of its own acquisition or the acquisition by persons acting in concert with it or by persons acting for their account, directly or indirectly holds
more than 30% of the voting securities in a Belgian listed company, are not applicable to us.

Squeeze-out

Pursuant to Article 513 of the Belgian Company Code and the regulations promulgated thereunder, a person or legal entity, or different persons or
legal entities acting alone or in concert, who own together with the company 95% of the securities with voting rights in a public company are entitled to acquire the totality of the securities with voting



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rights in that company following a squeeze-out offer. The securities that are not voluntarily tendered in response to such an offer are deemed to be
automatically transferred to the bidder at the end of the procedure. At the end of the procedure, the company is no longer deemed a public company, unless bonds issued by the company are still spread among the public. The consideration for the
securities must be in cash and must represent the fair value (verified by an independent expert) in order to safeguard the interests of the transferring shareholders.

The DGCL provides for stockholder appraisal rights, or the right to demand payment in cash of the judicially determined fair value of the stockholders
shares, in connection with certain mergers and consolidations.

Limitations on the Right to Own Securities

Neither Belgian law nor our articles of association impose any general limitation on the right of non-residents or
foreign persons to hold our securities or exercise voting rights on our securities other than those limitations that would generally apply to all shareholders.

Description of the Rights and Benefits Attached To Our Shares

Right to Attend and Vote at Our Shareholders Meetings

Annual Shareholders Meeting

Our annual
shareholders meeting will be held on the first Tuesday in June of each year, at 10 a.m., or at any other time, at our registered office or at any other place in Belgium mentioned in the notice of the meeting. If this date falls on a legal
holiday in Belgium, the meeting is held on the next business day in Belgium (excluding Saturday) at the same time.

Special and Extraordinary
Shareholders Meetings

Our board of directors or the statutory auditor (or the liquidators, if appropriate) may, whenever our interests so
require, convene a special or extraordinary shareholders meeting. Such shareholders meeting must also be convened when one or more shareholders holding at least one-fifth of our share capital so
demands.

Under the DGCL, special meetings of the stockholders of a Delaware corporation may be called by such person or persons as may be authorized by
the certificate of incorporation or by the bylaws of the corporation, or if not so designated, as determined by the board of directors. Stockholders generally do not have the right to call meetings of stockholders unless that right is granted in the
certificate of incorporation or the bylaws.

Notices Convening Shareholders Meetings

Notices of our shareholders meetings contain the agenda of the meeting indicating the items to be discussed as well as any proposed resolutions that will
be submitted at the meeting. Other than in connection with a demand to convene a special or extraordinary shareholders meeting as described above, shareholders may not submit matters to be voted upon at our shareholders meetings.

Notices are sent 15 days prior to the date of our shareholders meeting to the holders of our registered shares, holders of our registered warrants and
convertible bonds, and to our directors and our statutory auditor.

We publish on our website the notices of all our shareholders meetings and all
related documents, such as specific board and auditors reports.

Under the DGCL, unless otherwise provided in the certificate of incorporation or by-laws, written notice of any meeting of the stockholders of a Delaware corporation must be given to each stockholder entitled to vote at the meeting not less than 10 nor more than 60 days before the date of the
meeting and shall specify the place, date, hour, and, in the case of a special meeting, the purpose of the meeting.

Admission to Meetings

All holders of our shares are entitled to attend our shareholders meeting, take part in the deliberations and, within the limits prescribed by the
Belgian Company Code, vote.



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Shareholders wishing to attend and participate in the shareholders meeting must have the ownership of their
shares recorded in their names on the third business day preceding the day of the meeting through registration in the shareholders register. Our board of directors may make attendance and participation in the shareholders meeting subject
to a requirement for shareholders to express, on a date prior to the meeting to be determined by our board of directors, their intention to attend the meeting and the number of shares in respect of which they intend to exercise voting rights.

Votes

Each of our ordinary shares is entitled to one
vote except for shares owned by us, or by any of our direct subsidiaries, the voting rights of which are suspended.

Voting rights can also be suspended
in relation to shares:



| |  |  | which are not fully paid-up, notwithstanding the request thereto of our
board of directors;
| | - |  | -------------------------------------------------------------------------------------------



| |  |  | to which more than one person, or a legal entity represented by two or more persons acting as a board, is
entitled, except in the event a single representative is appointed for the exercise of the voting rights; and
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | for which the voting rights were suspended by a competent court.
| | - |  | ----------------------------------------------------------------

The ordinary shares held by our principal shareholders do not entitle such shareholders to different voting rights, except that as long as Wilfried Vancraen,
our founder and Chief Executive Officer, Hilde Ingelaere, an Executive Vice President of our company who is also Mr. Vancraens spouse, and their three children, Linde, Sander and Jeroen Vancraen, or collectively, the Family Shareholders,
control, directly or indirectly, in the aggregate at least 20% of the voting rights attached to our ordinary shares company, a majority of our directors must be appointed by our shareholders from a list of candidates proposed by the Family
Shareholders.

Any shareholder with the right to vote may either personally participate in the meeting or give a proxy to another person, who need not be
a shareholder, to represent such shareholder at the meeting. All proxies must be in writing in accordance with the form prescribed by us and must be received by us no later than the date determined by our board of directors. Our articles of
association do not allow shareholders to vote electronically.

Quorum and Majority Requirements

Generally, there is no quorum requirement for our shareholders meetings, except as provided for by law in relation to decisions regarding certain
matters. Decisions are made by a simple majority, except where the law provides for a special majority.

Under the DGCL, the certificate of incorporation
or bylaws of a Delaware corporation may specify the number of shares required to constitute a quorum but in no event shall a quorum consist of less than one-third of shares entitled to vote at a meeting. In
the absence of such specifications, a majority of shares entitled to vote shall constitute a quorum.

Matters involving special legal quorum and majority
requirements include, among others, amendment to the articles of association, issues of new shares, convertible bonds or warrants and decisions regarding mergers and demergers, which require at least 50% of the share capital to be present or
represented and the affirmative vote of the holders of at least 75% of the votes cast. If the quorum is not reached, a second meeting may be convened at which no quorum requirement applies. The special majority requirement for voting, however,
remains applicable.

Any modification of our corporate purpose or legal form requires a quorum of shareholders holding an aggregate of at least 50% of the
share capital and approval by a majority of at least 80% of the share capital present or represented. If there is no quorum, a second meeting must be convened. At the second meeting, no quorum is required, but the relevant resolution must be
approved by a majority of at least 80% of the share capital present or represented.



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Right to Ask Questions at our Shareholders Meeting

Within the limits of Article 540 of the Belgian Company Code, members of the board of directors will answer, during the shareholders meeting, the
questions raised by shareholders. Shareholders can ask questions either during the meeting or in writing, provided that we receive the written questions at the latest on the third business day preceding the shareholders meeting.

Dividends

All shares participate equally in our
profits (if any) as of and for the entire fiscal year starting on January 1. In general, we may only pay dividends if approved at our shareholders meeting, although our board of directors may, subject to certain conditions, pay an interim
dividend without shareholder approval in accordance with the provisions of the Belgian Company Code. Dividends are paid on the dates and at the places determined by our board of directors.

The Belgian Company Code provides that dividends can only be paid up to an amount equal to the excess of our shareholders equity over the sum of (i) paid-up or called-up share capital and (ii) reserves not available for distribution pursuant to law or the articles of association. Under Belgian law and our
articles of association, we must allocate at least 5% of our annual net profit under our statutory non-consolidated accounts (prepared in accordance with Belgian GAAP) to a legal reserve until the reserve
equals 10% of our share capital. Our legal reserve currently meets this requirement.

Under the DGCL, a Delaware corporation may pay dividends out of its
surplus (the excess of net assets over capital), or in case there is no surplus, out of its net profits for the fiscal year in which the dividend is declared and/or the preceding fiscal year (provided that the amount of the capital of the
corporation is not less than the aggregate amount of the capital represented by the issued and outstanding stock of all classes having a preference upon the distribution of assets). Dividends may be paid in the form of shares, property or cash.

Appointment of Directors

Our articles of
association provide that, as long as the Family Shareholders control, directly or indirectly, in the aggregate at least 20% of the voting rights attached to our ordinary shares company, a majority of our directors must be appointed by our
shareholders from a list of candidates proposed by the Family Shareholders.

Liquidation Rights

Our company can only be dissolved by a shareholders resolution passed with a majority of at least 75% of the votes cast at an extraordinary
shareholders meeting where at least 50% of the share capital is present or represented.

Under the DGCL, unless the board of directors approves the
proposal to dissolve, dissolution of a Delaware corporation must be approved by stockholders holding 100% of the total voting power of the corporation. Only if the dissolution is initiated by the board of directors may it be approved by a simple
majority of the corporations outstanding shares. The DGCL allows a Delaware corporation to include in its certificate of incorporation a supermajority voting requirement in connection with dissolutions initiated by the board.

In the event of the dissolution and liquidation of our company, the assets remaining after payment of all debts and liquidation expenses will be distributed
to the holders of our shares, each receiving a sum on a pro rata basis.

If, as a result of losses incurred, the ratio of our net assets (determined in
accordance with Belgian legal and accounting rules) to share capital is less than 50%, our board of directors must convene a general shareholders meeting within two months of the date upon which our board of directors discovered or should have
discovered this undercapitalization. At this shareholders meeting our board of directors needs to propose either our dissolution or our continuation, in which case our board of directors must propose measures to address our financial
situation. Our



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board of directors must justify its proposals in a special report to the shareholders. Shareholders representing at least 75% of the votes validly cast at this meeting have the right to dissolve
us, provided that at least 50% of our share capital is present or represented at the meeting.

If, as a result of losses incurred, the ratio of our net
assets to share capital is less than 25%, the same procedure must be followed, it being understood, however, that in the event shareholders representing 25% of the votes validly cast at the meeting can decide to dissolve us. If the amount of our net
assets has dropped below 61,500 (the minimum amount of share capital of a Belgian limited liability company), any interested party is entitled to request the competent court to dissolve us. The court can order our dissolution or grant a grace
period during which time we must remedy the situation.

Holders of ordinary shares have no sinking fund, redemption or appraisal rights.

American Depositary Shares Representing Our Ordinary Shares

The Bank of New York Mellon serves as the depositary for the ADSs. Each ADS represents one ordinary share (or a right to receive one ordinary share) deposited
with the principal Amsterdam office of ING Securities Services, Inc., as custodian for the depositary. Each ADS also represents any other securities, cash or other property which may be held by the depositary. The depositarys corporate trust
office at which the ADSs are administered is located at 240 Greenwich Street, New York, New York 10286. The Bank of New York Mellons principal executive office is located at 240 Greenwich Street, New York, New York 10286.

You may hold ADSs either (i) directly (x) by having an American Depositary Receipt, or ADR, which is a certificate evidencing a specific number of
ADSs, registered in your name, or (y) by having ADSs registered in your name in the Direct Registration System, or (ii) indirectly by holding a security entitlement in ADSs through your broker or other financial institution. If you hold
ADSs directly, you are a registered ADS holder, or ADS holder. This description assumes you are an ADS holder. If you hold the ADSs indirectly, you must rely on the procedures of your broker or other financial institution to assert the rights of ADS
holders described in this section. You should consult with your broker or financial institution to find out what those procedures are.

The Direct
Registration System, or DRS, is a system administered by The Depository Trust Company, or DTC, pursuant to which the depositary may register the ownership of uncertificated ADSs, which ownership is evidenced by periodic statements sent by the
depositary to the registered holders of uncertificated ADSs.

As an ADS holder, we will not treat you as one of our shareholders and you will not have
shareholder rights. Belgian law governs shareholder rights. The depositary will be the holder of the ordinary shares underlying your ADSs. As a registered holder of ADSs, you will have the rights of an ADS holder. A deposit agreement among us, the
depositary and the ADS holders sets out the ADS holder rights as well as the rights and obligations of the depositary. New York law governs the deposit agreement and the ADSs.

Dividends and Other Distributions

How will you
receive dividends and other distributions on the ordinary shares?

The depositary has agreed to pay to ADS holders the cash dividends or other
distributions it or the custodian receives on ordinary shares or other deposited securities, after deducting its fees and expenses. You will receive these distributions in proportion to the number of ordinary shares your ADSs represent.

Cash. We have no present intention of declaring or paying any cash dividends or cash distributions on our ordinary shares in the foreseeable
future. In the event we do declare or pay any cash dividends or cash distributions, the depositary will convert any cash dividend or other cash distribution we pay on the ordinary shares into U.S. dollars, if it can do so on a reasonable basis and
can transfer the U.S. dollars to the United States. If it is not possible and lawful to do so on a reasonable basis, or if any government approval is needed and cannot be obtained, the deposit agreement allows the depositary to distribute the
foreign currency only to those ADS holders to whom it is possible to do so. It will hold the foreign currency it cannot convert for the account of the ADS holders who have not been paid. It will not invest the foreign currency and it will not be
liable for any interest.



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Before making a distribution, any taxes or other governmental charges, together with fees and expenses of the
depositary that must be paid will be deducted. It will distribute only whole U.S. dollars and cents and will round fractional cents to the nearest whole cent. If the exchange rates fluctuate during a time when the depositary cannot convert the
foreign currency, you may lose some or all of the value of the distribution.

Shares. We have no present intention of declaring or paying
any share dividends or other distributions of our ordinary shares in the foreseeable future. In the event of a share dividend or other distribution of ordinary shares, the depositary may distribute additional ADSs representing such ordinary shares.
The depositary will only distribute whole ADSs. It will sell shares which would require it to deliver a fractional ADS and distribute the net proceeds in the same way as it does with cash. If the depositary does not distribute additional ADSs, the
Depositary will consult with us in good faith concerning the appropriate treatment of such additional ordinary shares. The depositary may sell a portion of the distributed ordinary shares sufficient to pay its fees and expenses in connection with
that distribution.

Rights to Purchase Additional Ordinary Shares. If we offer holders of our securities any rights to subscribe for
additional ordinary shares or any other rights, the depositary may make these rights available to ADS holders. If the depositary decides it is not legal and practical to make the rights available but that it is practical to sell the rights, the
depositary will use reasonable efforts to sell the rights and distribute the proceeds in the same way as it does with cash. The depositary will allow rights that are not distributed or sold to lapse. In that case, you will receive no value for them.

If the depositary makes rights available to ADS holders, it will exercise the rights and purchase the ordinary shares on your behalf. The depositary will
then deposit the ordinary shares and deliver ADSs to the persons entitled to them. It will only exercise rights if you pay the exercise price and any other charges required to be paid in order to exercise the rights.

U.S. securities laws may restrict transfers or the cancellation of the ADSs representing ordinary shares purchased upon the exercise of rights. For example,
you may not be able to trade these ADSs freely in the United States. In this case, the depositary may deliver restricted depositary shares that have the same terms as the ADSs described in this section except for changes needed to put the necessary
restrictions in place.

Other Distributions. The depositary will send to ADS holders anything else we distribute on deposited securities by
any means it determines is legal, fair and practical. If it cannot make the distribution in that way, the depositary has a choice. It may decide to sell what we distributed and distribute the net proceeds, in the same way as it does with cash. Or,
it may decide to hold what we distributed, in which case ADSs will also represent the newly distributed property. However, the depositary is not required to distribute any securities (other than ADSs) to ADS holders unless it receives satisfactory
evidence from us that it is legal to make that distribution. The depositary may sell a portion of the distributed securities or property sufficient to pay its fees and expenses in connection with that distribution.

The depositary is not responsible if it decides that it is unlawful or impractical to make a distribution available to any ADS holders. We have no obligation
to register ADSs, ordinary shares, rights or other securities under the Securities Act. We also have no obligation to take any other action to permit the distribution of ADSs, ordinary shares, rights or anything else to ADS holders. This means that
ADS holders may not receive the distributions we make on our ordinary shares or any value for them if it is illegal or impractical for us to make them available to ADS holders.

Deposit, Withdrawal and Cancellation

How are
ADSs issued?

The depositary will deliver ADSs if you or your broker deposit ordinary shares or evidence of rights to receive ordinary shares with the
custodian. Upon payment of its fees and expenses and of any taxes or charges, such as stamp taxes or share transfer taxes or fees, and delivery of any required endorsements, certifications or other instruments of transfer required by the depositary,
the depositary will register the appropriate number of ADSs in the names you request and will deliver the ADSs to or upon the order of the person or persons that made the deposit.



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How can you withdraw the deposited securities?

You may surrender your ADSs at the depositarys corporate trust office. Upon payment of its fees and expenses and of any taxes or charges, such as stamp
taxes or share transfer taxes or fees, the depositary will deliver the ordinary shares and any other deposited securities underlying the ADSs to you or a person designated by you at the office of the custodian. Or, at your request, risk and expense,
the depositary will deliver the deposited securities at its corporate trust office, if feasible.

How can you interchange between certificated ADSs and
uncertificated ADSs?

You may surrender your ADR to the depositary for the purpose of exchanging your ADR for uncertificated ADSs. The depositary will
cancel that ADR and will send to you a statement confirming that you are the registered holder of uncertificated ADSs. Alternatively, upon receipt by the depositary of a proper instruction from a registered holder of uncertificated ADSs requesting
the exchange of uncertificated ADSs for certificated ADSs, the depositary will execute and deliver to you an ADR evidencing those ADSs.

Voting
Rights

How do you vote?

You may instruct the
depositary how to vote the number of deposited ordinary shares your ADSs represent. The depositary will notify you of shareholders meetings and arrange to deliver our voting materials to you if we ask it to. Those materials will describe the
matters to be voted on and explain how you may instruct the depositary how to vote. For instructions to be valid, they must reach the depositary by a date set by the depositary.

Otherwise, you will not be able to exercise your right to vote unless you withdraw the ordinary shares. However, you may not know about the meeting with
sufficient advance notice to withdraw the ordinary shares.

The depositary will try, to the extent practicable, and subject to the laws of Belgium and
to our articles of association, bylaws or similar documents, to vote or to have its agents vote the ordinary shares or other deposited securities as instructed by you. If we requested the depositary to act at least 30 days prior to the meeting date
and the depositary does not receive voting instructions from you by the specified date, it will consider you to have instructed it to give a discretionary proxy to a person designated by us with respect to the number of deposited securities
represented by your ADSs, provided that no such instruction will be deemed given with respect to any matter as to which we inform the depositary (and we will provide such information as promptly as practicable, if applicable) that substantial
opposition exists or such matter materially and adversely affects the rights of holders of ordinary shares. The depositary will only vote or attempt to vote as instructed or as described above. The depositary, as a shareholder on record, may either
personally participate in the meeting or give a proxy to another person to represent it at the meeting. Our articles of association do not allow shareholders to vote electronically.

We cannot assure you that you will receive the voting materials in time to ensure that you can instruct the depositary to vote your ordinary shares. In
addition, the depositary and its agents are not responsible for failing to carry out voting instructions or for the manner of carrying out voting instructions. This means that you may not be able to exercise your right to vote and there may be
nothing you can do if your ordinary shares are not voted as you requested.

In order to give you a reasonable opportunity to instruct the depositary as to
the exercise of voting rights relating to deposited securities, if we request the depositary to act, we agree to give the depositary notice of any such meeting and details concerning the matters to be voted upon at least 15 days in advance of the
meeting date.

Fees and Expenses

What fees
and expenses will you be responsible for paying?

Pursuant to the terms of the deposit agreement, you will be required to pay the following fees to the
depositary:



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|                                                                                                                                                                                               |  |                                                                                                                                                          
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------
|Persons depositing or withdrawing ordinary shares or ADS holders must pay to the depositary:                                                                                                   |  | For:                                                                                                                                                     
|                                                                                                                                                                                               | 
|$5.00 (or less) per 100 ADSs (or portion of 100 ADSs)                                                                                                                                          |  | Issuance of ADSs, including issuances resulting from a distribution of ordinary shares or rights or other property                                       
|                                                                                                                                                                                               | 
|                                                                                                                                                                                               |  | Cancellation of ADSs for the purpose of withdrawal, including if the deposit agreement terminates                                                        
|                                                                                                                                                                                               | 
|$0.05 (or less) per ADS                                                                                                                                                                        |  | Any cash distribution to you                                                                                                                             
|                                                                                                                                                                                               | 
|A fee equivalent to the fee that would be payable if securities distributed to you had been ordinary shares and the shares had been deposited for issuance of ADSs                             |  | Distribution of securities distributed to holders of deposited securities which are distributed by the depositary to you                                 
|                                                                                                                                                                                               | 
|$0.05 (or less) per ADS per calendar year                                                                                                                                                      |  | Depositary services                                                                                                                                      
|                                                                                                                                                                                               | 
|Registration or transfer fees                                                                                                                                                                  |  | Transfer and registration of ordinary shares on our share register to or from the name of the depositary or its agent when you deposit or withdraw shares
|                                                                                                                                                                                               | 
|Expenses of the depositary                                                                                                                                                                     |  | Cable, telex and facsimile transmissions (when expressly provided in the deposit agreement) converting foreign currency to U.S. dollars                  
|                                                                                                                                                                                               | 
|Taxes and other governmental charges the depositary or the custodian has to pay on any ADS or ordinary shares underlying an ADS, such as share transfer taxes, stamp duty or withholding taxes |  | As necessary                                                                                                                                             
|                                                                                                                                                                                               | 
|Any charges incurred by the depositary or its agents for servicing the deposited securities                                                                                                    |  | As necessary                                                                                                                                             

The depositary collects its fees for delivery and surrender of ADSs directly from investors depositing ordinary shares or
surrendering ADSs for the purpose of withdrawal or from intermediaries acting for them. The depositary collects fees for making distributions to investors by deducting those fees from the amounts distributed or by selling a portion of distributable
property to pay the fees. The depositary may collect its annual fee for depositary services by deduction from cash distributions or by directly billing investors or by charging the book-entry system accounts of participants acting for them. The
depositary may collect any of its fees by deduction from any cash distribution payable to ADS holders that are obligated to pay those fees. The depositary may generally refuse to provide fee-based services
until its fees for those services are paid.

From time to time, the depositary may make payments to us to reimburse or share revenue from the fees
collected from ADS holders, or waive fees and expenses for services provided, generally relating to costs and expenses arising out of establishment and maintenance of the ADS program. In performing its duties under the deposit agreement, the
depositary may use brokers, dealers or other service providers that are affiliates of the depositary and that may earn or share fees or commissions.

Payment of Taxes

You will be responsible for any
taxes or other governmental charges payable on your ADSs or on the deposited securities represented by any of your ADSs. The depositary may refuse to register any transfer of your ADSs or



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allow you to withdraw the deposited securities represented by your ADSs until such taxes or other charges are paid. It may apply payments owed to you or sell deposited securities represented by
your ADSs to pay any taxes owed and you will remain liable for any deficiency. If the depositary sells deposited securities, it will, if appropriate, reduce the number of ADSs to reflect the sale and pay to ADS holders any proceeds, or send to ADS
holders any property, remaining after it has paid the taxes.

Reclassifications, Recapitalizations and Mergers



|                                                                                                                                                                                                        |  |                                                                                                                                                                                                  
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|If we:                                                                                                                                                                                                  |  | Then:                                                                                                                                                                                            
|                                                                                                                                                                                                        | 
|  Change the nominal or par value of our ordinary shares
   Reclassify, split up or
consolidate any of the deposited securities                                                                       |  | The cash, ordinary shares or other securities received by the depositary will become deposited securities. Each ADS will automatically
represent its equal share of the new deposited securities.
|  Distribute securities on the ordinary shares that are not distributed to you
   Recapitalize, reorganize,
merge, liquidate, sell all or substantially all of our assets, or take any similar action |  | The depositary may distribute new ADSs representing the new deposited securities or ask you to surrender your outstanding ADRs in exchange for new ADRs identifying the new deposited securities.

Amendment and Termination

How may the deposit agreement be amended?

We may agree
with the depositary to amend the deposit agreement and the ADRs without your consent for any reason. If an amendment adds or increases fees or charges, except for taxes and other governmental charges or expenses of the depositary for registration
fees, facsimile costs, delivery charges or similar items, or materially prejudices a substantial right of ADS holders, it will not become effective for outstanding ADSs until 30 days after the depositary notifies ADS holders of the amendment. At the
time an amendment becomes effective, you are considered, by continuing to hold your ADSs, to agree to the amendment and to be bound by the ADRs and the deposit agreement as amended.

How may the deposit agreement be terminated?

The
depositary will terminate the deposit agreement at our direction by mailing notice of termination to the ADS holders then outstanding at least 30 days prior to the date fixed in such notice for such termination. The depositary may also terminate the
deposit agreement by mailing notice of termination to us and the ADS holders if 60 days have passed since the depositary told us it wants to resign but a successor depositary has not been appointed and accepted its appointment.

After termination, the depositary and its agents will do the following under the deposit agreement but nothing else: collect distributions on the deposited
securities, sell rights and other property, and deliver ordinary shares and other deposited securities upon cancellation of ADSs. Four months after termination, the depositary may sell any remaining deposited securities by public or private sale.
After that, the depositary will hold the money it received on the sale, as well as any other cash it is holding under the deposit agreement for the pro rata benefit of the ADS holders that have not surrendered their ADSs. It will not invest the
money and has no liability for interest. The depositarys only obligations will be to account for the money and other cash. After termination our only obligations will be to indemnify the depositary and to pay fees and expenses of the
depositary that we agreed to pay.

Limitations on Obligations and Liability

Limits on our obligations and the obligations of the depositary; limits on liability to holders of ADSs



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The deposit agreement expressly limits our obligations and the obligations of the depositary. It also limits our
liability and the liability of the depositary or any of our respective directors, officers, employees, agents or affiliates. We and the depositary and our respective directors, officers, employees, agents or affiliates:



| |  |  | are only obligated to take the actions specifically set forth in the deposit agreement without negligence or bad
faith;
| | - |  | -----------------------------------------------------------------------------------------------------------------------



| |  |  | are not liable if we are or it is prevented or delayed by law or circumstances beyond our control from performing
our or its obligations under the deposit agreement;
| | - |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | are not liable if we or it exercises discretion permitted under the deposit agreement;
| | - |  | --------------------------------------------------------------------------------------



| |  |  | are not liable for the inability of any holder of ADSs to benefit from any distribution on deposited securities
that is not made available to holders of ADSs under the terms of the deposit agreement, or for any special, consequential or punitive damages for any breach of the terms of the deposit agreement;
| | - |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | are not liable for any tax consequences to any holders of ADSs on account of their ownership of ADSs;
| | - |  | -----------------------------------------------------------------------------------------------------



| |  |  | have no obligation to become involved in a lawsuit or other proceeding related to the ADSs or the deposit
agreement on your behalf or on behalf of any other person; and
| | - |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | may rely upon any documents we believe or it believes in good faith to be genuine and to have been signed or
presented by the proper person.
| | - |  | --------------------------------------------------------------------------------------------------------------------------------------------

In the deposit agreement, we and the depositary agree to indemnify each other under certain
circumstances. Additionally, we, the depositary and each owner and holder of ADSs waives the right to a jury trial in an action against us or the depositary arising out of or relating to the ordinary shares or other deposited securities, ADSs, ADRs
or the deposit agreement.

Requirements for Depositary Actions

Before the depositary will deliver or register a transfer of an ADS, make a distribution on an ADS, or permit withdrawal of ordinary shares, the depositary may
require:



| |  |  | payment of share transfer or other taxes or other governmental charges and transfer or registration fees charged
by third parties for the transfer of any ordinary shares or other deposited securities;
| | - |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | satisfactory proof of the identity and genuineness of any signature or other information it deems necessary; and
| | - |  | ----------------------------------------------------------------------------------------------------------------



| |  |  | compliance with regulations it may establish, from time to time, consistent with the deposit agreement, including
presentation of transfer documents.
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------

The depositary may refuse to deliver ADSs or register transfers of ADSs when the transfer books of
the depositary or our transfer books are closed or at any time if the depositary or we think it advisable to do so.

Your Right to Receive the
Ordinary Shares Underlying Your ADSs

ADS holders have the right to cancel their ADSs and withdraw the underlying ordinary shares at any time
except:



| |  |  | when temporary delays arise because: (i) the depositary has closed its transfer books or we have closed our
transfer books; (ii) the transfer of ordinary shares is blocked to permit voting at a shareholders meeting; or (iii) we are paying a dividend on our ordinary shares;
| | - |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | when you owe money to pay fees, taxes and similar charges; and
| | - |  | --------------------------------------------------------------



| |  |  | when it is necessary to prohibit withdrawals in order to comply with any laws or governmental regulations that
apply to ADSs or to the withdrawal of ordinary shares or other deposited securities.
| | - |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

This right of withdrawal may not be limited by any
other provision of the deposit agreement.



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Pre-release of ADSs

The deposit agreement permits the depositary to deliver ADSs before deposit of the underlying ordinary shares. This is called a
pre-release of the ADSs. The depositary may also deliver ordinary shares upon surrender and cancellation of pre-released ADSs (even if the ADSs are cancelled before the pre-release transaction has been closed out). A pre-release is closed out as soon as the underlying ordinary shares are delivered to the depositary. The depositary may accept
ADSs instead of ordinary shares to close out a pre-release. The depositary may pre-release ADSs only under the following conditions: (1) before or at the time of
the pre-release, the person to whom the pre-release is being made represents to the depositary and agrees in writing that it or its customer (i) owns or represents
the owner of the shares to be deposited (ii) assigns all beneficial right, title and interest in such shares to the depositary in its capacity as such and for the benefit of the ADS holders, and (iii) will not take any action with respect
to such shares that is inconsistent with the transfer of beneficial ownership (including without the consent of the depositary, disposing of such shares), other than in satisfaction of such pre-release;
(2) the pre-release is fully collateralized with cash or other collateral that the depositary considers appropriate; and (3) the depositary must be able to close out the pre-release on not more than five business days notice. In addition, the depositary will limit the number of ADSs that may be outstanding at any time as a result of
pre-release, which limit will normally be 30% of the ordinary shares deposited under the deposit agreement, although the depositary may disregard the limit from time to time if it thinks it is appropriate to
do so.

Direct Registration System

In the
deposit agreement, all parties to the deposit agreement acknowledge that the DRS and Profile Modification System, or Profile, will apply to uncertificated ADSs upon acceptance thereof to DRS by DTC. DRS is the system administered by DTC under which
the depositary may register the ownership of uncertificated ADSs, which ownership will be confirmed by periodic statements sent by the depositary to the registered holders of uncertificated ADSs. Profile is a required feature of DRS that allows a
DTC participant, claiming to act on behalf of a registered holder of ADSs, to direct the depositary to register a transfer of those ADSs to DTC or its nominee and to deliver those ADSs to the DTC account of that DTC participant without receipt by
the depositary of prior authorization from the ADS holder to register that transfer.

In connection with and in accordance with the arrangements and
procedures relating to DRS and Profile, the parties to the deposit agreement understand that the depositary will not verify, determine or otherwise ascertain whether the DTC participant that is claiming to be acting on behalf of an ADS holder in
requesting registration of transfer and delivery described in the paragraph above has the actual authority to act on behalf of the ADS holder (notwithstanding any requirements under the Uniform Commercial Code). In the deposit agreement, the parties
agree that the depositarys reliance on and compliance with instructions received by the depositary through the DRS/Profile system and in accordance with the deposit agreement will not constitute negligence or bad faith on the part of the
depositary.

Shareholder Communications; Inspection of Register of Holders of ADSs; ADS Holder Information

The depositary will make available for your inspection at its office all communications that it receives from us as a holder of deposited securities that we
make generally available to holders of deposited securities. The depositary will send you copies of those communications if we ask it to. You have a right to inspect the register of holders of ADSs, but not for the purpose of contacting those
holders about a matter unrelated to our business or the ADSs.

Each holder of ADSs will be required to provide such information as from time to time may
be requested by us or as may otherwise be required to be disclosed, in accordance with applicable law, the rules and requirements of any stock exchange or clearing system on which the ADSs are traded or our articles of association.



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