QURE uniQure NV

DESCRIPTION OF ORDINARY SHARES

        The description below of our ordinary shares and provisions of our articles of association are summaries and are qualified by reference to our articles of association and the applicable provisions of Dutch law.

        The following description of the general terms and provisions of our ordinary shares is a summary only and therefore is not complete and is subject to, and qualified in its entirety by reference to, the terms and provisions of our articles of association. Our articles of association have been filed with the SEC as an exhibit to the registration statement of which this prospectus forms a part and you should read the articles for provisions that may be important to you.

Authorized Ordinary Shares

        Our articles of association provide an authorized share capital of 60,000,000 ordinary shares, each with a nominal value per share of €0.05. As of June 13, 2018, we had 37,069,095 ordinary shares issued and outstanding. We do not have any preferred shares authorized or outstanding.

Form of Ordinary Shares

        We issue our ordinary shares in registered book-entry form and such shares are not certificated.

Issuance of Ordinary Shares

        We may issue ordinary shares subject to the maximum prescribed by our authorized share capital contained in our articles of association. Our board of directors has the power to issue ordinary shares if and only to the extent that the general meeting has designated to the board of directors such authority. Currently our articles of association provide for an authorized share capital which amounts to €3,000,000 and is divided into one class of shares, being 60,000,000 ordinary shares, each with a nominal value of €0.05 per share. A designation of authority to the board of directors to issue ordinary shares remains effective for the period specified by the general meeting and may be granted up to a

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maximum of five years from the date of designation. The general meeting may renew this designation annually.

        Without this designation, only the general meeting has the power to authorize the issuance of ordinary shares upon the proposal of the board of directors. Currently, our board of directors is authorized to issue ordinary shares until December 13, 2019 under the restrictions specified in our articles of association and the designation.

        In connection with the issuance of ordinary shares, at least the nominal value must be paid for such shares. No obligation other than to pay up the nominal amount of and any premium agreed upon a share may be imposed upon a shareholder against the shareholder's will, by amendment of the articles of association or otherwise. Subject to Dutch law, payment for shares must be in cash to the extent no other contribution has been agreed and may be made in the currency approved by us.

        Any increase in the number of authorized ordinary shares and the introduction of different classes of shares would require the approval of an amendment to our articles of association in order to effect such increase or introduction. Such amendment would need to be made by a proposal of the board of directors and adoption by the shareholders at a general meeting by a majority vote.

NASDAQ Global Market Listing

        Our ordinary shares are listed on The NASDAQ Global Market under the symbol "QURE."

Comparison of Dutch corporate law and our Articles of Association and Delaware corporate law

        The following comparison between Dutch corporate law, which applies to us, and Delaware corporate law, the law under which many publicly listed companies in the United States are incorporated, discusses additional matters not otherwise described in this prospectus. This summary is subject to Dutch law, including Book 2 of the Dutch Civil Code and Delaware corporation law, including the Delaware General Corporation Law.

Corporate governance

Duties of directors

        The Netherlands.    We have a one tier board structure consisting of our executive directors and non-executive directors. Under the one-tier board structure, both the executive and non-executive directors will be collectively responsible for the management performed by the one-tier board and for the general policy and strategy of a company. The executive directors are responsible for the day-to-day management of a company. The non-executive directors are responsible for supervising the conduct of, and providing advice to, the executive directors and for providing supervision with respect to the company's general state of affairs. Each executive director and non-executive director has a duty to act in the corporate interest of the company. Under Dutch law, the corporate interest extends to the interests of all corporate stakeholders, such as shareholders, creditors, employees, customers and suppliers. The duty to act in the corporate interest of the company also applies in the event of a proposed sale or split-up of a company, whereby the circumstances generally dictate how such duty is to be applied. Any resolution of the board regarding a significant change in the identity or character of a company requires shareholders' approval.

        Delaware.    The board of directors bears the ultimate responsibility for managing the business and affairs of a corporation. In discharging this function, directors of a Delaware corporation owe fiduciary duties of care and loyalty to the corporation and to its stockholders. Delaware courts have decided that the directors of a Delaware corporation are required to exercise informed business judgment in the performance of their duties. Informed business judgment means that the directors have informed themselves of all material information reasonably available to them. Delaware courts have also imposed

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a heightened standard of conduct upon directors of a Delaware corporation who take any action designed to defeat a threatened change in control of the corporation. In addition, under Delaware law, when the board of directors of a Delaware corporation approves the sale or break-up of a corporation, the board of directors may, in certain circumstances, have a duty to obtain the highest value reasonably available to the stockholders.

Director terms

        The Netherlands.    Under Dutch law, executive directors of a listed company are generally appointed for a term of a maximum of four years and reappointed for a term of a maximum of four years at a time. Non-executive directors of a listed company are generally appointed for a term of a maximum of four years and reappointed once for another term of a maximum of four years. Non-executive directors of a listed company may subsequently be reappointed for a term of a maximum of two years, which reappointment may be extended by at most two years. Our executive and non-executive directors are, in principle, appointed by the general meeting of shareholders upon the binding nomination of the non-executive directors.

        The general meeting of shareholders is entitled at all times to suspend or dismiss a director. The general meeting of shareholders may only adopt a resolution to suspend or dismiss such director by at least a two-thirds majority of the votes cast, if such majority represents more than half of the issued share capital of the company.

        Delaware.    The Delaware General Corporation Law generally provides for a one-year term for directors, but permits directorships to be divided into up to three classes with up to three-year terms, with the years for each class expiring in different years, if permitted by a company's certificate of incorporation, an initial bylaw or a bylaw adopted by the stockholders. A director elected to serve a term on such a classified board may not be removed by stockholders without cause. There is no limit in the number of terms a director may serve.

Director vacancies

        The Netherlands.    Under Dutch law, directors are appointed by the general meeting of shareholders. Under our articles of association, directors are, in principle, appointed by the general meeting of shareholders upon the binding nomination by the non-executive directors. However, the general meeting of shareholders may at all times overrule such binding nomination by a resolution adopted by at least a two-thirds majority of the votes cast, provided such majority represents more than half of the issued share capital of our company. If the general meeting of shareholders overrules the binding nomination, the non-executive directors must make a new nomination.

        Delaware.    The Delaware General Corporation Law provides that vacancies and newly created directorships may be filled by a majority of the directors then in office (even though less than a quorum) unless (1) otherwise provided in the certificate of incorporation or bylaws of the corporation or (2) the certificate of incorporation directs that a particular class of stock is to elect such director, in which case any other directors elected by such class, or a sole remaining director elected by such class, will fill such vacancy.

Conflict-of-interest transactions

        The Netherlands.    Pursuant to Dutch law and our articles of association, directors may not take part in any discussion or decision-making that involves a subject or transaction in relation to which they have a personal direct or indirect conflict of interest with us. Our articles of association provide that if as a result thereof, the board is unable to act the resolution will be adopted by the general meeting of shareholders.

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        Delaware.    The Delaware General Corporation Law generally permits transactions involving a Delaware corporation and an interested director of that corporation if:

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the material facts as to the director's relationship or interest are disclosed and a majority of disinterested directors consent;



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the material facts are disclosed as to the director's relationship or interest and a majority of shares entitled to vote thereon consent; or



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the transaction is fair to the corporation at the time it is authorized by the board of directors, a committee of the board of directors or the stockholders.

Shareholder rights

Voting rights

        The Netherlands.    In accordance with Dutch law and our articles of association, each issued ordinary share confers the right to cast one vote at the general meeting of shareholders. Each holder of ordinary shares may cast as many votes as it holds shares. Shares that are held by us or our direct or indirect subsidiaries do not confer the right to vote. Dutch law does not permit cumulative voting for the election of executive directors and non-executive directors.

        For each general meeting of shareholders, a record date will be applied with respect to ordinary shares in order to establish which shareholders are entitled to attend and vote at a specific general meeting of shareholders. Such record date is set by the board. The record date and the manner in which shareholders can register and exercise their rights will be set out in the convocation notice of the meeting.

        Delaware.    Under the Delaware General Corporation Law, each stockholder is entitled to one vote per share of stock, unless the certificate of incorporation provides otherwise. In addition, the certificate of incorporation may provide for cumulative voting at all elections of directors of the corporation, or at elections held under specified circumstances. Either the certificate of incorporation or the bylaws may specify the number of shares and/or the amount of other securities that must be represented at a meeting in order to constitute a quorum, but in no event will a quorum consist of less than one third of the shares entitled to vote at a meeting.

        Stockholders as of the record date for the meeting are entitled to vote at the meeting, and the board of directors may fix a record date that is no more than 60 nor less than ten days before the date of the meeting, and if no record date is set then the record date is the close of business on the day next preceding the day on which notice is given, or if notice is waived then the record date is the close of business on the day next preceding the day on which the meeting is held. The determination of the stockholders of record entitled to notice or to vote at a meeting of stockholders shall apply to any adjournment of the meeting, but the board of directors may fix a new record date for the adjourned meeting.

Shareholder proposals

        The Netherlands.    Pursuant to our articles of association, extraordinary general meetings of shareholders will be convened by the board or by those who are authorized by law or pursuant to our articles of association to do so. Pursuant to Dutch law, one or more shareholders representing at least one-tenth of the issued share capital of the company may request the Dutch courts to order that they be authorized by the court to convene a general meeting of shareholders. The court shall disallow the request if it does not appear that the applicants have previously requested the board to convene a general meeting of shareholders and the board has taken the necessary steps so that the general meeting of shareholders could be held within six weeks after the request.

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        The agenda for a general meeting of shareholders must include such items requested by one or more shareholders representing at least 3% of the issued share capital of a company or such lower percentage as the articles of association may provide. Our articles of association do not state such lower percentage.

        Delaware.    Delaware law does not specifically grant stockholders the right to bring business before an annual or special meeting. However, if a Delaware corporation is subject to the SEC's proxy rules, a stockholder who owns at least $2,000 in market value, or 1% of the corporation's securities entitled to vote, may propose a matter for a vote at an annual or special meeting in accordance with those rules.

Action by written consent

        The Netherlands.    Under Dutch law, the articles of association of a company may provide that shareholders' resolutions may be adopted in writing without holding a general meeting of shareholders, provided that the resolution is adopted unanimously by all shareholders that are entitled to vote. For a listed company, this method of adopting resolutions is not feasible.

        Delaware.    Although permitted by Delaware law, publicly listed companies do not typically permit stockholders of a corporation to take action by written consent.

Appraisal rights

        The Netherlands.    The concept of appraisal rights does not exist under Dutch law. However, pursuant to Dutch law a shareholder who for its own account contributes at least 95% of our issued share capital may initiate proceedings against our minority shareholders jointly for the transfer of their shares to it. The proceedings are held before the Enterprise Chamber (Ondernemingskamer). The Enterprise Chamber may grant the claim for squeeze-out in relation to all minority shareholders and will determine the price to be paid for the shares, if necessary after appointment of one or three experts who will offer an opinion to the Enterprise Chamber on the value to be paid for the shares of the minority shareholders.

        Furthermore, in accordance with Directive 2005/56/EC of the European Parliament and the Council of October 26, 2005 on cross-border mergers of limited liability companies, Dutch law provides that, to the extent the acquiring company in a cross-border merger is organized under the laws of another EU member state, a shareholder of a Dutch disappearing company who has voted against the cross-border merger may file a claim with the Dutch company for compensation. The compensation is to be determined by one or more independent experts.

        Delaware.    The Delaware General Corporation Law 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.

Shareholder suits

        The Netherlands.    In the event a third party is liable to a Dutch company, only a company itself can bring a civil action against that third party. An individual shareholder does not have the right to bring an action on behalf of a company. This individual shareholder may, in its own name, have an individual right to take action against such third party in the event that the cause for the liability of that third party also constitutes a tortious act directly against that individual shareholder. The Dutch Civil Code provides for the possibility to initiate such action collectively. A collective action can be instituted by a foundation or an association whose objective is to protect the rights of a group of persons having similar interests. The collective action itself cannot result in an order for payment of monetary damages but may only result in a declaratory judgment (verklaring voor recht). In order to obtain compensation for damages, the foundation or association and the defendant may reach—often

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on the basis of such declaratory judgment—a settlement. A Dutch court may declare the settlement agreement binding upon all the injured parties with an opt-out choice for an individual injured party. An individual injured party may also itself—outside the collective action—institute a civil claim for damages.

        Delaware.    Under the Delaware General Corporation Law, a stockholder may bring a derivative action on behalf of the corporation to enforce the rights of the corporation. An individual also may commence a class action suit on behalf of himself and other similarly situated stockholders where the requirements for maintaining a class action under Delaware law have been met. A person may institute and maintain such a suit only if that person was a stockholder at the time of the transaction which is the subject of the suit. In addition, under Delaware case law, the plaintiff normally must be a stockholder at the time of the transaction that is the subject of the suit and throughout the duration of the derivative suit. Delaware law also requires that the derivative plaintiff make a demand on the directors of the corporation to assert the corporate claim before the suit may be prosecuted by the derivative plaintiff in court, unless such a demand would be futile.

Repurchase of shares

        The Netherlands.    Under Dutch law, a company such as ours may not subscribe for newly issued shares in its own share capital. Such company may, however, subject to certain restrictions under Dutch law and its articles of association, acquire shares in its own share capital. We may acquire fully paid-up shares in our own share capital at any time for no valuable consideration. Furthermore, subject to certain provisions of Dutch law and our articles of association, we may repurchase fully paid-up shares in our own share capital if (1) such repurchase would not cause our shareholders' equity to fall below an amount equal to the sum of the paid-up and called-up part of the issued share capital and the reserves we are required to maintain pursuant to applicable law and (2) we would not as a result of such repurchase hold more than 50% of our own issued share capital.

        Other than shares acquired for no valuable consideration, ordinary shares may only be acquired following a resolution of our board, acting pursuant to an authorization for the repurchase of shares granted by the general meeting of shareholders. An authorization by the general meeting of shareholders for the repurchase of shares can be granted for a maximum period of 18 months. Such authorization must specify the number of shares that may be acquired, the manner in which these shares may be acquired and the price range within which the shares may be acquired. Our board has been authorized, for a period of 18 months to be calculated from the date of the annual general meeting of shareholders held on June 13, 2018, to cause the repurchase of ordinary shares by us of up to 10% of our issued share capital, for a price per share between the nominal value of the ordinary shares and an amount of 110% of the highest price of the ordinary shares officially quoted on any of the official stock markets we are listed on during any of 30 banking days preceding the date the repurchase is effected or proposed.

        No authorization of the general meeting of shareholders is required if fully paid-up ordinary shares are acquired by us with the intention of transferring such ordinary shares to our employees under an applicable employee stock purchase plan, provided such ordinary shares are officially quoted on any of the official stock markets.

        Delaware.    Under the Delaware General Corporation Law, a 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. A Delaware corporation may, however, purchase or redeem out of capital any of its preferred shares or, if no preferred shares are outstanding, any of its own shares if such shares will be retired upon acquisition and the capital of the corporation will be reduced in accordance with specified limitations.

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Anti-takeover provisions

        The Netherlands.    Under Dutch law, various protective measures are possible and permissible within the boundaries set by Dutch statutory law and Dutch case law. We have adopted several provisions that may have the effect of making a takeover of our company more difficult or less attractive, including:

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the staggered four-year terms of our directors, as a result of which only approximately one-fourth of our non-executive directors will be subject to election in any one year;



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a provision that our directors may only be removed at the general meeting of shareholders by a two-thirds majority of votes cast representing more than half of our issued share capital; and



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requirements that certain matters, including an amendment of our articles of association, may only be brought to our shareholders for a vote upon a proposal by our board.

        Delaware.    In addition to other aspects of Delaware law governing fiduciary duties of directors during a potential takeover, the Delaware General Corporation Law also contains a business combination statute that protects Delaware companies from hostile takeovers and from actions following the takeover by prohibiting some transactions once an acquirer has gained a significant holding in the corporation.

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Section 203 of the Delaware General Corporation Law prohibits "business combinations," including mergers, sales and leases of assets, issuances of securities and similar transactions by a corporation or a subsidiary with an interested stockholder that beneficially owns 15% or more of a corporation's voting stock, within three years after the person becomes an interested stockholder, unless: the transaction that will cause the person to become an interested stockholder is approved by the board of directors of the target prior to the transactions;



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after the completion of the transaction in which the person becomes an interested stockholder, the interested stockholder holds at least 85% of the voting stock of the corporation not including shares owned by persons who are directors and representatives of interested stockholders and shares owned by specified employee benefit plans; or



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after the person becomes an interested stockholder, the business combination is approved by the board of directors of the corporation and holders of at least 66.67% of the outstanding voting stock, excluding shares held by the interested stockholder.

        A Delaware corporation may elect not to be governed by Section 203 by a provision contained in the original certificate of incorporation of the corporation or an amendment to the original certificate of incorporation or to the bylaws of the company, which amendment must be approved by a majority of the shares entitled to vote and may not be further amended by the board of directors of the corporation. Such an amendment is not effective until twelve months following its adoption.

Inspection of books and records

        The Netherlands.    Our board provides the shareholders, at the general meeting of shareholders, with all information that the shareholders require for the exercise of their powers, unless doing so would be contrary to an overriding interest of ours. Our board must give reason for electing not to provide such information on the basis of an overriding interest.

        Delaware.    Under the Delaware General Corporation Law, any stockholder may inspect certain of the corporation's books and records, for any proper purpose, during the corporation's usual hours of business.

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Removal of directors

        The Netherlands.    Under our articles of association, the general meeting of shareholders is at all times entitled to suspend or dismiss a director. The general meeting of shareholders may only adopt a resolution to suspend or dismiss such a member by at least a two-thirds majority of the votes cast, provided such majority represents more than half of the issued share capital of our company.

        Delaware.    Under the Delaware General Corporation Law, any director or the entire board of directors may be removed, with or without cause, by the holders of a majority of the shares then entitled to vote at an election of directors, except (1) unless the certificate of incorporation provides otherwise, in the case of a corporation whose board is classified, stockholders may effect such removal only for cause, or (2) in the case of a corporation having cumulative voting, if less than the entire board is to be removed, no director may be removed without cause if the votes cast against his removal would be sufficient to elect him if then cumulatively voted at an election of the entire board of directors, or, if there are classes of directors, at an election of the class of directors of which he is a part.

Preemptive rights

        The Netherlands.    Under Dutch law, in the event of an issuance of ordinary shares, each shareholder will have a pro rata preemptive right in proportion to the aggregate nominal value of the ordinary shares held by such holder (with the exception of ordinary shares to be issued to employees or ordinary shares issued against a contribution other than in cash). Under our articles of association, the preemptive rights in respect of newly issued ordinary shares may be restricted or excluded by a resolution of the general meeting of shareholders upon proposal of our board. The general meeting of shareholders may designate our board to restrict or exclude the preemptive rights in respect of newly issued ordinary shares. Such designation can be granted for a period not exceeding five years. A resolution of the general meeting of shareholders to restrict or exclude the preemptive rights or to designate the board as the authorized body to do so requires a two-thirds majority of the votes cast, if less than one half of our issued share capital is represented at the meeting.

        At our annual general meeting of shareholders held on June 13, 2018, the general meeting of shareholders resolved to authorize our board for a period of 18 months with effect from the date of the meeting to restrict or exclude preemptive rights accruing to shareholders in connection with the issue of ordinary shares or rights to subscribe for ordinary shares.

        Delaware.    Under the Delaware General Corporation Law, stockholders 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 certificate of incorporation.

Dividends

        The Netherlands.    Dutch law provides that dividends may be distributed after adoption of the annual accounts by the general meeting of shareholders from which it appears that such dividend distribution is allowed. Moreover, dividends may be distributed only to the extent that the shareholders' equity exceeds the amount of the paid-up and called-up part of the issued share capital of the company and the reserves that must be maintained under the law or the articles of association. Interim dividends may be declared as provided in the articles of association and may be distributed to the extent that the shareholders' equity exceeds the amount of the paid-up and called-up part of the issued share capital of the company and the reserves that must be maintained under the law or the articles of association, as apparent from an interim statement of assets and liabilities.

        Under our articles of association, any amount of profit may be carried to a reserve as our board determines. After reservation by our board of any profit, the remaining profit will be at the disposal of

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the shareholders. Our corporate policy is to only make a distribution of dividends to our shareholders after the adoption of our annual accounts demonstrating that such distribution is legally permitted. However, our board is permitted to declare interim dividends without the approval of the general meeting of shareholders.

        Dividends will be made payable not later than thirty days after the date they were declared unless the body declaring the dividend determines a different date. Claims to dividends not made within five years and one day from the date that such dividends became payable will lapse and any such amounts will be considered to have been forfeited to us (verjaring).

        Delaware.    Under the Delaware General Corporation Law, 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). In determining the amount of surplus of a Delaware corporation, the assets of the corporation, including stock of subsidiaries owned by the corporation, must be valued at their fair market value as determined by the board of directors, without regard to their historical book value. Dividends may be paid in the form of shares, property or cash.

Shareholder vote on certain reorganizations

        The Netherlands.    Under Dutch law, the general meeting of shareholders must approve resolutions of the board relating to a significant change in the identity or the character of the company or the business of the company, which includes:

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a transfer of the business or virtually the entire business to a third party;



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the entry into or termination of a long-term cooperation of the company or a subsidiary with another legal entity or company or as a fully liable partner in a limited partnership or general partnership, if such cooperation or termination is of a far-reaching significance for the company; and



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the acquisition or divestment by the company or a subsidiary of a participating interest in the capital of a company having a value of at least one third of the amount of its assets according to its balance sheet and explanatory notes or, if the company prepares a consolidated balance sheet, according to its consolidated balance sheet and explanatory notes, according to the last adopted annual accounts of the company.

        Delaware.    Under the Delaware General Corporation Law, the vote of a majority of the outstanding shares of capital stock entitled to vote thereon generally is necessary to approve a merger or consolidation or the sale of all or substantially all of the assets of a corporation. The Delaware General Corporation Law permits a corporation to include in its certificate of incorporation a provision requiring for any corporate action the vote of a larger portion of the stock or of any class or series of stock than would otherwise be required.

        Under the Delaware General Corporation Law, no vote of the stockholders of a surviving corporation to a merger is needed, however, unless required by the certificate of incorporation, if (1) the agreement of merger does not amend in any respect the certificate of incorporation of the surviving corporation, (2) the shares of stock of the surviving corporation are not changed in the merger and (3) the number of shares of common stock of the surviving corporation into which any other shares, securities or obligations to be issued in the merger may be converted does not exceed 20% of the surviving corporation's common stock outstanding immediately prior to the effective date of the merger. In addition, stockholders may not be entitled to vote in certain mergers with other corporations that own 90% or more of the outstanding shares of each class of stock of such corporation, but the stockholders will be entitled to appraisal rights.

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Remuneration of directors

        The Netherlands.    Under Dutch law and our articles of association, we must adopt a remuneration policy for our directors. Such remuneration policy shall be adopted by the general meeting of shareholders upon the proposal of our non-executive directors. The remuneration of our executive directors will be determined by our non-executive directors with due observance of our remuneration policy; the remuneration of our non-executive directors will be determined by the board with due observance of our remuneration policy.

        Delaware.    Under the Delaware General Corporation Law, the stockholders do not generally have the right to approve the compensation policy for directors or the senior management of the corporation, although certain aspects of executive compensation may be subject to binding or advisory stockholder votes due to the provisions of U.S. federal securities and tax law, as well as stock exchange requirements.

DESCRIPTION OF DEBT SECURITIES

        In this section, references to "holders" mean those who own debt securities registered in their own names on the books that uniQure N.V. or the indenture trustee maintains for this purpose, and not those who own beneficial interests in debt securities registered in street name or in debt securities issued in book-entry form through one or more depositaries. Owners of beneficial interests in the debt securities should read the section below entitled "Book-Entry Procedures and Settlement."

General

        The debt securities offered by this prospectus will be either senior or subordinated debt. Senior debt securities or subordinated debt securities may be convertible or exchangeable into our ordinary shares or other securities as described under "—Convertible or Exchangeable Securities" below. We will issue senior debt under a senior debt indenture, we will issue subordinated debt under a subordinated debt indenture and we will issue convertible debt securities under a convertible debt indenture. We sometimes refer to the senior debt indenture, the subordinated debt indenture and the convertible debt indenture individually as an indenture and collectively as the indentures. The indentures will be between us and a trustee. The terms of the indenture governing the convertible debt securities will be substantially similar to the terms of the indenture governing the senior debt securities described below, except that the indenture governing the convertible debt securities will include provisions with respect to the conversion of such convertible debt securities, omit certain provisions described under "—Defeasance" below, prohibit any modification to the terms of convertibility without the consent of the holders and permit any holder to institute action to enforce such terms of convertibility. The indentures are exhibits to the registration statement of which this prospectus forms a part. You can obtain copies of the indentures by following the directions outlined in "Where You Can Find Additional Information" or by contacting the indenture trustee.

        The following briefly summarizes the material provisions of the indentures and the debt securities, other than pricing and related terms which will be disclosed for a particular series of debt securities in a prospectus supplement. You should read the more detailed provisions of the applicable indenture, including the defined terms, for provisions that may be important to you. You should also read the particular terms of a series of debt securities, which will be described in more detail in a prospectus supplement. Wherever particular sections or defined terms of the applicable indenture are referred to, such sections or defined terms are incorporated into this prospectus by reference, and the statement in this prospectus is qualified by that reference.

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        The indentures provide that our debt securities may be issued in one or more series, with different terms, in each case as we authorize from time to time. We also have the right to reopen a previous issue of a series of debt securities by issuing additional debt securities of such series.

Information in the Prospectus Supplement

        The prospectus supplement for any offered series of debt securities will describe the following terms, as applicable:

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the title or designation of the offered debt securities;



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whether the debt is senior or subordinated;



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whether there is any collateral securing the debt securities;



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whether the debt securities are convertible or exchangeable into other securities;



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the aggregate principal amount offered and the authorized denominations;



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the initial public offering price;



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the maturity date or dates;



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any sinking fund or other provision for payment of the debt securities prior to their stated maturity;



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whether the debt securities are fixed rate debt securities or floating rate debt securities or original issue discount debt securities;



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if the debt securities are fixed rate debt securities, the yearly rate at which the debt securities will bear interest, if any;



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if the debt securities are floating rate debt securities, the method of calculating the interest rate;



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if the debt securities are original issue discount debt securities, their yield to maturity;



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the date or dates from which any interest will accrue, or how such date or dates will be determined, and the interest payment dates and any related record dates;



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if other than in U.S. Dollars, the currency or currency unit in which payment will be made;



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any provisions for the payment of additional amounts for taxes;



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the denominations in which the currency or currency unit of the securities will be issuable if other than denominations of $1,000 and integral multiples thereof;



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the terms and conditions on which the debt securities may be redeemed at the option of the Company;



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any obligation of the Company to redeem, purchase or repay the debt securities at the option of a holder upon the happening of any event and the terms and conditions of redemption, purchase or repayment;



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the names and duties of any co-indenture trustees, depositaries, authenticating agents, calculation agents, paying agents, transfer agents or registrars for the debt securities;



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any material provisions of the applicable indenture described in this prospectus that do not apply to the debt securities;



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the ranking of the specific series of debt securities relative to other outstanding indebtedness;

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if the debt securities are subordinated, the aggregate amount of outstanding indebtedness, as of a recent date, that is senior to the subordinated securities, and any limitation on the issuance of additional senior indebtedness;



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the place where we will pay principal and interest;



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additional provisions, if any, relating to the defeasance of the debt securities;



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any United States federal income tax consequences, if material;



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the dates on which premium, if any, will be paid;



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our right, if any, to defer payment of interest and the maximum length of this deferral period;



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any listing of the debt securities on a securities exchange; and



•

any other specific terms of the debt securities.

        We will issue the debt securities only in registered form. As currently anticipated, debt securities of a series will trade in book-entry form, and global notes will be issued in physical (paper) form, as described below under "Book-Entry Procedures and Settlement."

Senior Debt

        We will issue senior debt securities under the senior debt indenture. These senior debt securities will rank on an equal basis with all our other unsecured debt except subordinated debt.

Subordinated Debt

        We will issue subordinated debt securities under the subordinated debt indenture. Subordinated debt will rank subordinate and junior in right of payment, to the extent set forth in the subordinated debt indenture, to all our senior debt (both secured and unsecured).

        In general, the holders of all senior debt are first entitled to receive payment of the full amount unpaid on senior debt before the holders of any of the subordinated debt securities are entitled to receive a payment on account of the principal or interest on the indebtedness evidenced by the subordinated debt securities in certain events.

        If we default in the payment of any principal of, or premium, if any, or interest on any senior debt when it becomes due and payable after any applicable grace period, then, unless and until the default is cured or waived or ceases to exist, we cannot make a payment on account of or redeem or otherwise acquire the subordinated debt securities.

        If there is any insolvency, bankruptcy, liquidation or other similar proceeding relating to us or our property, then all senior debt must be paid in full before any payment may be made to any holders of subordinated debt securities.

        Furthermore, if we default in the payment of the principal of and accrued interest on any subordinated debt securities that is declared due and payable upon an event of default under the subordinated debt indenture, holders of all our senior debt will first be entitled to receive payment in full in cash before holders of such subordinated debt can receive any payments.

        Senior debt means:

•

the principal, premium, if any, interest and any other amounts owing in respect of indebtedness of the Company and/or of our subsidiaries that may guarantee our debt for money borrowed and indebtedness evidenced by securities, notes, debentures, bonds or other similar instruments issued by us, including the senior debt securities and letters of credit;

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•

all capitalized lease obligations;



•

all hedging obligations;



•

all obligations representing the deferred purchase price of property; and



•

all deferrals, renewals, extensions and refundings of obligations of the type referred to above;

        but senior debt does not include:

•

subordinated debt securities; and



•

any indebtedness that by its terms is subordinated to, or ranks on an equal basis with, our subordinated debt securities.

Convertible Debt

        We will issue convertible debt securities under the convertible debt indenture. Convertible debt securities will be convertible into ordinary shares on the terms set forth in the convertible debt indenture. The convertible debt indenture will provide that the conversion price is subject to customary anti-dilution adjustments in connection with stock dividends, stock splits, stock combinations, reclassifications and other similar events.

Covenants

        Amalgamation and Sale of Assets.    We may not, in a single transaction or a series of related transactions:

•

consolidate, amalgamate or merge with or into any other person; or



•

directly or indirectly, transfer, sell, lease or otherwise dispose of all or substantially all of our assets,

unless, in either such case:

•

in a transaction in which we do not survive or in which we sell, lease or otherwise dispose of all or substantially all of our assets, the successor entity to us expressly assumes, by a supplemental indenture executed and delivered to the indenture trustee in a form reasonably satisfactory to the indenture trustee, all of our obligations under the indenture;



•

immediately before and after giving effect to the transaction, no default on the debt securities exists; and



•

an officer's certificate and an opinion of counsel setting forth certain statements are delivered to the indenture trustee.

        Other Covenants.    In addition, any offered series of debt securities may have additional covenants which will be described in the prospectus supplement, limiting or restricting, among other things:

•

our ability to incur indebtedness;



•

our ability to pay dividends, to repurchase or redeem our capital stock;



•

our ability to create dividend and other payment restrictions affecting our subsidiaries;



•

mergers and consolidations by us;



•

sales of assets by us;



•

our ability to enter into transactions with affiliates;



•

our ability to incur liens; and

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•

our ability to enter into sale and leaseback transactions.

Modification of the Indentures

        Under the indentures, we and the indenture trustee may amend the indentures, without the consent of any holder of the debt securities to:

•

cure ambiguities, defects or inconsistencies;



•

comply with the covenants described under "—Amalgamation and Sale of Assets";



•

add to our covenants for the benefit of the holders of all or any series of debt securities (and if such covenants are to be for the benefit of less than all series of debt securities, stating that such covenants are expressly being included for the benefit of such series) or to surrender any rights or power conferred upon us;



•

add any additional events of default for the benefit of the holders of all or a series of debt securities;



•

establish the form or terms of debt securities of any series;



•

provide for uncertificated debt securities in addition to or in place of certificated debt securities;



•

secure the debt securities of one or more series;



•

evidence the succession of another person to the Company and the assumption of the covenants in the indentures and in the debt securities by such successor; or any co-issuer of the debt securities;



•

add or change any provision of the indentures to permit the issuance of the debt securities in bearer form, registrable or not registrable as to principal, with or without interest coupons;



•

appoint a successor indenture trustee;



•

add to, change or eliminate any provision of the indentures so long as such addition, change or elimination does not affect the rights of the holders; or



•

conform any provision of the indentures to the description of securities contained in this prospectus or any similar provision in any prospectus supplement relating to an offer of a series of debt securities under the indentures.

        We and the indenture trustee may, with the consent of the holders of at least a majority in aggregate principal amount of the debt securities of a series, modify the applicable indenture or the rights of the holders of the securities of such series. However, no such modification may, without the consent of each holder of an affected debt security:

•

extend the fixed maturity of any such debt securities;



•

reduce the rate or change the time of payment of interest on such debt securities;



•

reduce the principal amount of such securities or the premium, if any, on such debt securities;



•

change or waive the redemption provisions of such debt securities;



•

change any obligation of ours to maintain an office or agency;



•

reduce the amount of the principal payable on acceleration of any debt securities issued originally at a discount;



•

adversely affect in any material respect the ranking on such debt securities;



•

adversely affect in any material respect the right, if any, to convert such debt securities;

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•

adversely affect any right of repayment or repurchase at the option of the holder;



•

reduce or postpone any sinking fund or similar provision;



•

change the currency or currency unit in which any such debt securities are payable or the right of selection thereof;



•

impair the right to sue for the enforcement of any payment on such debt securities;



•

reduce the percentage of debt securities of a series whose holders need to consent to the modification or a waiver; or



•

with respect to subordinated debt securities, modify or change any provisions of the indenture or the related definitions affecting the subordination or ranking of any debt securities, in a manner which adversely affects the holders.

Defaults

        Each indenture provides that events of default regarding any series of debt securities will be:

•

our failure to pay required interest on any debt security of such series for 30 days;



•

our failure to pay principal or premium, if any, on any debt security of such series when due;



•

our failure to make any deposit of any sinking fund payment when due on debt securities of such series;



•

our failure to perform for 30 days after notice any other covenant in the relevant indenture other than a covenant included in the relevant indenture solely for the benefit of a series of debt securities other than the series at issue;



•

a breach by us of the covenant with respect to amalgamation and sale of assets;



•

our failure to pay beyond any applicable grace period, or the acceleration of, indebtedness in excess of $35,000,000; and



•

certain events of bankruptcy or insolvency, whether voluntary or not.

        If an event of default regarding debt securities of any series issued under the indentures should occur and be continuing, either the indenture trustee or the holders of 25% in the principal amount of outstanding debt securities of such series may declare each debt security of that series due and payable. If an event of default regarding debt securities results from certain events of bankruptcy, insolvency or reorganization with respect to us, such amount with respect to the debt securities will be due and payable immediately without any declaration or other act on the part of the holders of outstanding debt securities or the indenture trustee. We are required to file annually with the indenture trustee a statement of an officer as to the fulfillment by us of our obligations under the indenture during the preceding year.

        No event of default regarding one series of debt securities issued under an indenture is necessarily an event of default regarding any other series of debt securities.

        Holders of a majority in principal amount of the outstanding debt securities of any series will be entitled to control certain actions of the indenture trustee under an indenture and to waive past defaults regarding such series. The indenture trustee generally cannot be required by any of the holders of debt securities to take any action, unless one or more of such holders shall have provided to the indenture trustee satisfactory security or indemnity.

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        If an event of default occurs and is continuing regarding a series of debt securities, the indenture trustee may use any sums that it holds under the relevant indenture for its own reasonable compensation and expenses incurred prior to paying the holders of debt securities of such series.

        Before any holder of any series of debt securities may institute action for any remedy, the holders of not less than 25% in principal amount of the debt securities of that series outstanding must request the indenture trustee to take action. Holders must also offer and give satisfactory security and indemnity against liabilities incurred by the indenture trustee for taking such action, and the indenture trustee must have failed to institute any proceeding within 60 days after receiving such request and offer of indemnity. These limitations do not apply, however, to a suit by a holder of any series of debt securities to enforce payment of principal, interest or premium.

Defeasance

        After we have deposited with the indenture trustee cash or government securities, in trust for the benefit of the holders, sufficient to pay the principal of, premium, if any, and interest on the debt securities of such series when due, and satisfied certain other conditions, including receipt of an opinion of counsel that holders will not recognize taxable gain or loss for U.S. Federal income tax purposes, we may elect to have our obligations discharged with respect to the outstanding debt securities of any series ("defeasance and discharge"). Defeasance and discharge means that we will be deemed to have paid and discharged the entire indebtedness represented by the outstanding debt securities of such series under the applicable indenture, except for:

•

the rights of holders of the debt securities to receive principal, interest and any premium when due;



•

our obligations with respect to the debt securities concerning issuing temporary debt securities, registration of transfer of debt securities, mutilated, destroyed, lost or stolen debt securities and the maintenance of an office or agency for payment for security payments held in trust;



•

the rights, powers, trusts, duties and immunities of the indenture trustee; and



•

the defeasance provisions of the indenture.

        Alternatively, we may elect to have our obligations released with respect to certain covenants in the applicable indenture ("covenant defeasance"). Any omission to comply with these obligations will not constitute a default or an event of default with respect to the debt securities of any series. In the event covenant defeasance occurs, certain events, not including non-payment, bankruptcy and insolvency events, described under "Events of Default" will no longer constitute an event of default for that series.

Governing Law

        Unless otherwise stated in the prospectus supplement, the debt securities and the indentures will be governed by New York law.

Payment and Paying Agents

        Distributions on the debt securities other than those represented by global notes will be made in the designated currency against surrender of the debt securities at the corporate trust office of the indenture trustee. Payment will be made to the registered holder at the close of business on the record date for such payment. Interest payments will be made at the principal corporate trust office of the indenture trustee, or by a check mailed to the holder at his or her registered address. Payments in any other manner will be specified in the prospectus supplement applicable to the particular series of debt securities.

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Transfer and Exchange

        Debt securities may be presented for exchange, and debt securities other than a global security may be presented for registration of transfer, at the corporate trust office of the indenture trustee. Holders will not have to pay any service charge for any registration of transfer or exchange of debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with such registration of transfer or exchange of debt securities.

DESCRIPTION OF WARRANTS

        We may issue warrants to purchase our debt or equity securities or securities of third parties or other rights, including rights to receive payment in cash or securities based on the value, rate or price of one or more specified commodities, currencies, securities or indices, or any combination of the foregoing. Warrants may be issued independently or together with any other securities and may be attached to, or separate from, such securities. A series of warrants may be issued under a separate warrant indenture between us and a warrant agent. The terms of any warrants to be issued and a description of the material provisions of any applicable warrant indenture will be set forth in the applicable prospectus supplement.

        The applicable prospectus supplement will describe the following terms of any warrants in respect of which this prospectus is being delivered:

•

the title of such warrants;



•

the aggregate number of such warrants;



•

the price or prices at which such warrants will be issued;



•

the currency or currencies, in which the price of such warrants will be payable;



•

the securities or other rights, including rights to receive payment in cash or securities based on the value, rate or price of one or more specified commodities, currencies, securities or indices, or any combination of the foregoing, purchasable upon exercise of such warrants;



•

the price at which and the currency or currencies, in which the securities or other rights purchasable upon exercise of such warrants may be purchased;



•

the date on which the right to exercise such warrants shall commence and the date on which such right shall expire;



•

if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;



•

if applicable, the designation and terms of the securities with which such warrants are issued and the number of such warrants issued with each such security;



•

if applicable, the date on and after which such warrants and the related securities will be separately transferable;



•

information with respect to book-entry procedures, if any;



•

if applicable, a discussion of any material United States Federal income tax considerations; and



•

any other terms of such warrants, including terms, procedures and limitations relating to the exchange and exercise of such warrants.

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DESCRIPTION OF RIGHTS

        We may issue rights to purchase our securities. These rights may be issued independently or together with any other security offered by this prospectus and may or may not be transferable by the person receiving the rights in the rights offering. In connection with any rights offering, we may enter into a standby underwriting agreement with one or more underwriters pursuant to which the underwriter will purchase any securities that remain unsubscribed for upon completion of the rights offering.

        The applicable prospectus supplement relating to any rights will describe the terms of the offered rights, including, where applicable, the following:

•

the exercise price for the rights;



•

the number of rights issued to each securityholder;



•

the extent to which the rights are transferable;



•

any other terms of the rights, including terms, procedures and limitations relating to the exchange and exercise of the rights;



•

the date on which the right to exercise the rights will commence and the date on which the right will expire;



•

the amount of rights outstanding;



•

the extent to which the rights include an over-subscription privilege with respect to unsubscribed securities; and



•

the material terms of any standby underwriting arrangement entered into by us in connection with the rights offering.

DESCRIPTION OF PURCHASE CONTRACTS

        We may issue purchase contracts, including contracts obligating holders to purchase from us, and us to sell to the holders, a specified number of our ordinary shares at a future date or dates. The price per ordinary share and the number of ordinary shares may be fixed at the time the purchase contracts are issued or may be determined by reference to a specific formula set forth in the purchase contracts. The purchase contracts may require us to make periodic payments to holders or vice versa, and these payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under those contracts in a specified manner. The applicable prospectus supplement will describe the terms of the purchase contracts, including if applicable, any collateral arrangements.

DESCRIPTION OF UNITS

        We may issue units consisting of one or more debt securities, purchase contracts, warrants, rights, ordinary shares or any combination of such securities. The applicable prospectus supplement will describe:

•

the terms of the units and of the securities comprising the units, including whether and under what circumstances the securities comprising the units may be traded separately;



•

a description of the terms of any unit agreement governing the units; and



•

a description of the provisions for the payment, settlement, transfer or exchange or the units.

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CONVERTIBLE OR EXCHANGEABLE SECURITIES

        We may issue securities of the types described in this prospectus that are convertible or exchangeable into other securities described herein. The terms of such convertible or exchangeable securities will be set forth in a prospectus supplement.

SELLING SHAREHOLDERS

        This prospectus also relates to the possible resale by certain of our shareholders, who we refer to in the prospectus as the "selling shareholders," of ordinary shares. The ordinary shares to be sold by the selling shareholders pursuant to this prospectus were or will be issued by us to the selling shareholders in transactions exempt from the registration provisions of the Securities Act pursuant to the exemption set forth in Section 4(2) thereof relative to sales by an issuer not involving any public offering or in reliance on Regulation S under the Securities Act regarding sales by an issuer in offshore transactions.

        No selling shareholder will sell any ordinary shares pursuant to this prospectus until we have identified such selling shareholder and the ordinary shares being offered for resale by such selling shareholder in a prospectus supplement. The prospectus supplement for any offering by the selling shareholders of ordinary shares will include the following information:

•

the name of each participating selling shareholder;



•

the nature of any position, office, or other material relationship which each selling shareholder has had within the past three years with us or any of our predecessors or affiliates;



•

the number of ordinary shares held by each selling shareholder prior to the offering;



•

the number of ordinary shares to be offered for each selling shareholder's account; and



•

the number, and, if applicable, the percentage of ordinary shares held by each of the selling shareholders before and after completion of the sale of the maximum number of shares that may be offered by such selling shareholder under such prospectus supplements.

        Alternatively, we may provide this information in a post-effective amendment to the registration statement of which this prospectus forms a part or in a periodic or current report that we file pursuant to Section 13 or 15(d) of the Exchange Act and that is incorporated by reference into this prospectus. See "Incorporation of Certain Documents by Reference" for more information.

        We do not know when or in what amounts the selling shareholders may offer ordinary shares for sale of which selling shareholders will participate in any such offering. However, the selling shareholders may sell or transfer all or a portion of their ordinary shares pursuant to any available exemption from the registration requirements of the Securities Act.

FORM, EXCHANGE AND TRANSFER

        We will issue only in registered form; no securities will be issued in bearer form. We will issue each security in book-entry form only, unless otherwise specified in the applicable prospectus supplement. Securities in book-entry form will be represented by a global security registered in the name of a depositary, which will be the holder of all the securities represented by the global security. Those who own beneficial interests in a global security will do so through participants in the depositary's system, and the rights of these indirect owners will be governed solely by the applicable procedures of the depositary and its participants. Only the depositary will be entitled to transfer or exchange a security in global form, since it will be the sole holder of the security. These book-entry securities are described below under "Book-Entry Procedures and Settlement."

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        If any securities are issued in non-global form or cease to be book-entry securities (in the circumstances described in the next section), the following will apply to them:

•

The securities will be issued in fully registered form in denominations stated in the prospectus supplement. You may exchange securities for securities of the same series in smaller denominations or combined into fewer securities of the same series of larger denominations, as long as the total amount is not changed.



•

You may exchange, transfer, present for payment or exercise securities at the office of the relevant indenture trustee or agent indicated in the prospectus supplement. You may also replace lost, stolen, destroyed or mutilated securities at that office. We may appoint another entity to perform these functions or we may perform them ourselves.



•

You will not be required to pay a service charge to transfer or exchange your securities, but you may be required to pay any tax or other governmental charge associated with the transfer or exchange. The transfer or exchange, and any replacement, will be made only if our transfer agent is satisfied with your proof of legal ownership. The transfer agent may also require an indemnity before replacing any securities.



•

If we have the right to redeem, accelerate or settle any securities before their maturity or expiration, and we exercise that right as to less than all those securities, we may block the transfer or exchange of those securities during the period beginning 15 days before the day we mail the notice of exercise and ending on the day of that mailing, in order to freeze the list of holders to prepare the mailing. We may also refuse to register transfers of or exchange any security selected for early settlement, except that we will continue to permit transfers and exchanges of the unsettled portion of any security being partially settled.



•

If fewer than all of the securities represented by a certificate that are payable or exercisable in part are presented for payment or exercise, a new certificate will be issued for the remaining amount of securities.

BOOK-ENTRY PROCEDURES AND SETTLEMENT

        Most offered securities will be book-entry (global) securities. Upon issuance, all book-entry securities will be represented by one or more fully registered global securities, without coupons. Each global security will be deposited with, or on behalf of, The Depository Trust & Clearing Corporation, or DTC, a securities depositary, and will be registered in the name of Cede & Co. or another nominee of DTC. DTC, Cede & Co., or such nominee, will thus be the only registered holder of these securities. Except as set forth below, the registered global securities may be transferred, in whole but not in part, only to Cede & Co., another nominee of DTC or to a successor of DTC or its nominee.

        Purchasers of securities may only hold interests in the global securities through DTC if they are participants in the DTC system. Individual certificates in respect of the securities will not be issued in exchange for the registered global securities, except in very limited circumstances. Purchasers may also hold interests through a securities intermediary—banks, brokerage houses and other institutions that maintain securities accounts for customers—that has an account with DTC or its nominee. DTC will maintain accounts showing the security holdings of its participants, and these participants will in turn maintain accounts showing the security holdings of their customers. Some of these customers may themselves be securities intermediaries holding securities for their customers. Thus, each beneficial owner of a book-entry security will hold that security indirectly through a hierarchy of intermediaries, with DTC at the top and the beneficial owner's own securities intermediary at the bottom.

        The securities of each beneficial owner of a book-entry security will be evidenced solely by entries on the books of the beneficial owner's securities intermediary. The actual purchaser of the securities will generally not be entitled to have the securities represented by the global securities registered in its

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name and will not be considered the owner under the declaration. In most cases, a beneficial owner will also not be able to obtain a paper certificate evidencing the holder's ownership of securities. The book-entry system for holding securities eliminates the need for physical movement of certificates and is the system through which most publicly traded common stock (or in our case, ordinary shares) is held in the United States. However, the laws of some jurisdictions require some purchasers of securities to take physical delivery of their securities in definitive form. These laws may impair the ability to transfer book-entry securities.

        Title to book-entry interests in the securities will pass by book-entry registration of the transfer within the records of DTC in accordance with its procedures.

        If DTC notifies us that it is unwilling or unable to continue as a clearing system in connection with the registered global securities or ceases to be a clearing agency registered under the Exchange Act, and a successor clearing system is not appointed by us within 90 days after receiving that notice from DTC or upon becoming aware that DTC is no longer so registered, we will issue or cause to be issued individual certificates in registered form on registration of transfer of, or in exchange for, book-entry interests in the securities represented by registered global securities upon delivery of those registered global securities for cancellation. We may also permit beneficial owners of book-entry securities represented by a global security to exchange their beneficial interests for definitive (paper) securities if, in our sole discretion, we decide to allow some or all book-entry securities to be exchangeable for definitive securities in registered form.

        Unless we indicate otherwise, any global security that is exchangeable will be exchangeable in whole for definitive securities in registered form, with the same terms and of an equal aggregate principal amount. Definitive securities will be registered in the name or names of the person or persons specified by DTC in a written instruction to the registrar of the securities. DTC may base its written instruction upon directions that it receives from its participants.

        In this prospectus, for book-entry securities, references to actions taken by security holders will mean actions taken by DTC upon instructions from its participants, and references to payments and notices of redemption to security holders will mean payments and notices of redemption to DTC as the registered holder of the securities for distribution to participants in accordance with DTC's procedures.

        Initial settlement for the securities offered on a global basis through DTC will be made in immediately available funds. Secondary market trading between DTC's participants will occur in the ordinary way in accordance with DTC's rules and will be settled in immediately available funds using DTC's Same-Day Funds Settlement System.

        Although DTC has agreed to the foregoing procedures in order to facilitate transfers of interests in the securities among participants thereof, it is under no obligation to perform or continue to perform the foregoing procedures and these procedures may be changed or discontinued at any time.

        DTC is a limited purpose trust company organized under the laws of the State of New York, a member of the Federal Reserve System, a clearing corporation within the meaning of the New York Uniform Commercial Code and a clearing agency registered under section 17A of the Securities Exchange Act of 1934. The rules applicable to DTC and its participants are on file with the SEC.

        We will not have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interest in the book-entry securities or for maintaining, supervising or reviewing any records relating to the beneficial ownership interests.

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PLAN OF DISTRIBUTION

        We or the selling shareholder may offer the offered securities in one or more of the following ways from time to time:

•

to or through underwriters or dealers;



•

by ourselves directly;



•

through agents; or



•

through a combination of any of these methods of sale.

        In compliance with the guidelines of the Financial Industry Regulatory Authority, or FINRA, the maximum commission or discount to be received by any FINRA member or independent broker dealer may not exceed 8% of the aggregate principal amount of securities offered pursuant to this prospectus. We anticipate, however, that the maximum commission or discount to be received in any particular offering of securities will be significantly less than this amount.

        The prospectus supplement relating to a particular offering of securities will set forth the terms of such offering, including:

•

the type of securities to be offered;



•

the name or names of any underwriters, dealers or agents and the amounts of securities underwritten or purchased by each of them;



•

the purchase price of the offered securities and the proceeds to us from such sale;



•

any underwriting discounts and commissions or agency fees and other items constituting underwriters' or agents' compensation, which in the aggregate will not exceed 8% of the gross proceeds of the offering;



•

the initial public offering price;



•

any discounts or concessions to be allowed or reallowed or paid to dealers; and



•

any securities exchanges on which such offered securities may be listed.

        Any initial public offering prices, discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

        The distribution of the offered securities may be effected from time to time in one or more transactions at a fixed price or prices, which may be changed, at market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices.

        If underwriters are used in an offering of offered securities, such offered securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The securities may be either offered to the public through underwriting syndicates represented by one or more managing underwriters or by one or more underwriters without a syndicate. Unless otherwise set forth in the prospectus supplement, the underwriters will not be obligated to purchase offered securities unless specified conditions are satisfied, and if the underwriters do purchase any offered securities, they will purchase all offered securities.

        In connection with underwritten offerings of the offered securities and in accordance with applicable law and industry practice, underwriters may over-allot or effect transactions that stabilize, maintain or otherwise affect the market price of the offered securities at levels above those that might otherwise prevail in the open market, including by entering stabilizing bids, effecting syndicate covering transactions or imposing penalty bids, each of which is described below.

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•

A stabilizing bid means the placing of any bid, or the effecting of any purchase, for the purpose of pegging, fixing or maintaining the price of a security.



•

A syndicate covering transaction means the placing of any bid on behalf of the underwriting syndicate or the effecting of any purchase to reduce a short position created in connection with the offering.



•

A penalty bid means an arrangement that permits the managing underwriter to reclaim a selling concession from a syndicate member in connection with the offering when offered securities originally sold by the syndicate member are purchased in syndicate covering transactions.

        These transactions may be effected on an exchange or automated quotation system, if the securities are listed on that exchange or admitted for trading on that automated quotation system, or in the over-the-counter market or otherwise.

        If a dealer is utilized in the sales of offered securities, we or the selling shareholder will sell such offered securities to the dealer as principal. The dealer may then resell such offered securities to the public at varying prices to be determined by such dealer at the time of resale. Any such dealer may be deemed to be an underwriter, as such term is defined in the Securities Act, of the offered securities so offered and sold. The name of the dealer and the terms of the transaction will be set forth in the related prospectus supplement.

        We or the selling shareholder may enter into derivative transactions with third parties or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, such third parties (or their affiliates) may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, such persons may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of securities, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of securities. Such persons will be underwriters and, if not identified in this prospectus, will be identified in the applicable prospectus supplement (or a post-effective amendment).

        Sales to or through one or more underwriters or agents in at-the-market offerings will be made pursuant to the terms of a distribution agreement with the underwriters or agents. Such underwriters or agents may act on an agency basis or on a principal basis. During the term of any such agreement, shares may be sold on a daily basis on any stock exchange, market or trading facility on which the ordinary shares are traded, in privately negotiated transactions or otherwise as agreed with the underwriters or agents. The distribution agreement will provide that any ordinary share sold will be sold at negotiated prices or at prices related to the then prevailing market prices for our ordinary shares. Therefore, exact figures regarding proceeds that will be raised or commissions to be paid cannot be determined at this time and will be described in a prospectus supplement. Pursuant to the terms of the distribution agreement, we may also agree to sell, and the relevant underwriters or agents may agree to solicit offers to purchase, blocks of our ordinary shares or other securities. The terms of each such distribution agreement will be described in a prospectus supplement.

        We may sell our ordinary shares pursuant to dividend reinvestment, share purchase plans and similar plans in which our shareholders as well as other investors may participate. Purchasers of shares under such plans may, upon resales, be deemed to be underwriters. These shares may be resold in market transactions (including coverage of short positions), in privately negotiated transactions or otherwise. Ordinary shares sold under any such plans may be issued at a discount to the market price of the ordinary shares. The difference between the price owners who may be deemed to be underwriters pay us for our ordinary shares acquired under any such plan, after deduction of the applicable discount from the market price, and the price at which such shares are resold, may be

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deemed to constitute underwriting commissions or fees received by these owners in connection with such transactions.

        We may also issue our ordinary shares to officers, directors, employees, consultants, agents or other persons pursuant to awards made under our equity incentive plans. Such ordinary shares may be resold by our officers and directors under this prospectus as indicated in a prospectus supplement.

        We or the selling shareholder may loan ordinary shares to underwriters, agents and others, pursuant to share lending agreements, which may be offered for sale in transactions, including block sales, on any securities exchange, market or trading facility.

        We or the selling shareholder may loan or pledge securities to a financial institution or other third party that in turn may sell the securities using this prospectus. Such financial institution or third party may transfer its short position to investors in our securities or in connection with a simultaneous offering of other securities offered by this prospectus.

        Offered securities may be sold directly by us or the selling shareholder to one or more institutional purchasers, or through agents designated by us from time to time, at a fixed price or prices, which may be changed, or at varying prices determined at the time of sale. Any such agent may be deemed to be an underwriter as that term is defined in the Securities Act. Any agent involved in the offer or sale of the offered securities in respect of which this prospectus is delivered will be named, and any commissions payable by us to such agent will be set forth, in the prospectus supplement relating to that offering. Unless otherwise indicated in such prospectus supplement, any such agent will be acting on a best efforts basis for the period of its appointment.

        If so indicated in the applicable prospectus supplement, we or the selling shareholder(s) will authorize agents, underwriters or dealers to solicit offers from certain types of institutions to purchase offered securities from us at the public offering price set forth in such prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject only to those conditions set forth in the prospectus supplement and the prospectus supplement will set forth the commission payable for solicitation of such contracts.

        In addition, ordinary shares may be issued in exchange for debt securities.

        Each series of offered securities, other than the ordinary shares which are listed on the Nasdaq Global Select Market, will be a new issue of securities and will have no established trading market. Any underwriters to whom offered securities are sold for public offering and sale may make a market in such offered securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. The offered securities may or may not be listed on a national securities exchange. No assurance can be given that there will be a market for the offered securities.

        One or more firms, referred to as "remarketing firms," may also offer or sell the securities, if the prospectus supplement so indicates, in connection with a remarketing arrangement upon their purchase. Remarketing firms will act as principals for their own accounts or as agents for us. These remarketing firms will offer or sell the securities in accordance with a redemption or repayment pursuant to the terms of the securities. The prospectus supplement will identify any remarketing firm and the terms of its agreement, if any, with us and will describe the remarketing firm's compensation. Remarketing firms may be deemed to be underwriters in connection with the securities they remarket. Remarketing firms may be entitled under agreements that may be entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

        Underwriters, dealers, agents and remarketing firms may be entitled, under agreements with us, to indemnification by us against certain civil liabilities, including liabilities under the Securities Act

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relating to material misstatements and omissions, or to contribution with respect to payments which the underwriters, dealers or agents may be required to make in respect thereof. Underwriters, dealers, agents and remarketing firms may be customers of, engage in transactions with, or perform services for, us and our affiliates in the ordinary course of business.

LEGAL MATTERS

        Unless otherwise indicated in the applicable prospectus supplement, certain legal matters in connection with the offering and the validity of the securities offered by this prospectus, and any supplement thereto, will be passed upon for us by Morgan, Lewis & Bockius UK LLP. Certain legal matters with respect to Dutch law in connection with the validity of the shares being offered by this prospectus and other legal matters will be passed upon for us by Rutgers Posch Visée Endedijk N.V., Amsterdam, the Netherlands. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

        The financial statements incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2017 have been so incorporated in reliance on the report of PricewaterhouseCoopers Accountants N.V., an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy the registration statement, as well as any other document filed by us with the SEC, at the SEC's Public Reference Room at 100 F Street NE, Washington, D.C. 20549. You can also request copies of these documents by writing to the SEC and paying a fee for the copying cost. You may obtain information on the operation of the Public Reference Room by calling the SEC at (800) SEC-0330. The SEC maintains a website that contains reports, proxy statements and other information regarding issuers that file electronically with the SEC, including us. The address of the SEC website is www.sec.gov.

        We maintain a website at www.uniqure.com. Information contained in or accessible through our website does not constitute a part of this prospectus.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

        The SEC allows us to "incorporate by reference" information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The documents incorporated by reference into this prospectus contain important information that you should read about us. The information incorporated by reference is considered to be a part of this prospectus, and information in documents that we file later with the SEC will automatically update and supersede information contained in documents filed earlier with the SEC or contained in this prospectus.

        The following documents are incorporated by reference into this document:

•

our Form 8-A filed with the SEC on January 31, 2014;



•

our Annual Report on Form 10-K for the year ended December 31, 2017 and filed with the SEC on March 14, 2018;



•

our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018 and filed with the SEC on April 30, 2018;

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•

our Current Reports on Form 8-K filed on April 30, 2018, May 3, 2018 and May 3, 2018.

        We also incorporate by reference into this prospectus all documents (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date of the initial filing of the registration statement of which this prospectus forms a part and prior to effectiveness of the registration statement, or (ii) after the date of this prospectus but prior to the termination of the offering. These documents include periodic reports, such as Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as proxy statements. Information in these documents updates and supplements the information provided in this prospectus. Any statements in these documents will automatically be deemed to modify and supersede any information in any document we previously filed with the SEC that is incorporated or deemed to be incorporated herein by reference to the extent that statements in the later filed document modify or replace such earlier statements.

        We will provide to each person, including any beneficial owner, to whom a prospectus is delivered, without charge upon written or oral request, a copy of any or all of the documents that are incorporated by reference into this prospectus but not delivered with the prospectus, including exhibits which are specifically incorporated by reference into such documents. You should direct any requests for documents by writing us at 113 Hartwell Avenue, Lexington, MA 02421, or telephoning us at +1.339.970.7000.

        Any statement contained herein or in a document incorporated or deemed to be incorporated by reference into this document will be deemed to be modified or superseded for purposes of the document to the extent that a statement contained in this document or any other subsequently filed document that is deemed to be incorporated by reference into this document modifies or supersedes the statement.

DISCLOSURE OF COMMISSION'S POSITION ON INDEMNIFICATION FOR SECURITIES ACT LIABILITY

        Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers or persons controlling the Company pursuant to the foregoing provisions, we have been informed that 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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Up to $150,000,000

Ordinary Shares

PROSPECTUS SUPPLEMENT

SVB Leerink

March 2, 2020