ADC Therapeutics SA美股招股说明书(2025-12-12版)

ADC THERAPEUTICS SA 14,696,253 Common Shares Pursuant to this prospectus, the selling shareholders may offer an aggregate of 14,696,253 common shares from time totime if and to the extent as they may determine as described in the section entitled “Plan of Distribution” at prevailingmarket prices, at prices different than prevailing market prices or at privately negotiated prices. If any common shares aresold, the selling shareholders will pay any brokerage commissions and/or similar charges incurred for the sale of suchshares. As required by the securities purchase agreements, dated October 12, 2025, with the selling shareholders, we are filingthe registration statement of which this prospectus forms a part to permit the resale of 10,850,100 common shares and3,846,153 common shares issuable upon exercise of the pre-funded warrants, in each case, issued and sold to the sellingshareholders pursuant to such securities purchase agreements. We do not know whether, when or the extent to which theselling shareholders will sell the common shares. We are not selling any common shares included in this prospectus and will not receive any of the proceeds from the saleof any common shares by the selling shareholders pursuant to this prospectus. However, if the pre-funded warrants areexercised in cash, we may receive up to an aggregate of CHF 307,692 from such exercise, which will be used for workingcapital and general corporate purposes. Our common shares are listed on the New York Stock Exchange (“NYSE”) under the symbol “ADCT.” Investing in our common shares involves a high degree of risk. See the “Risk Factors” section beginning onpage4 of this prospectus and in our Securities and Exchange Commission (“SEC”) filings that are incorporatedby reference in this prospectus. Neither the Securities and Exchange Commission nor any state securities commission has approved ordisapproved of these securities or determined if this prospectus is truthful or complete. Any representation to thecontrary is a criminal offense. Prospectus datedDecember 12, 2025. TABLE OF CONTENTS ABOUT THIS PROSPECTUSPROSPECTUS SUMMARYRISK FACTORSCAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTSUSE OF PROCEEDSDIVIDEND POLICYDESCRIPTION OF SHARE CAPITAL AND ARTICLES OF ASSOCIATIONTAXATIONSELLING SHAREHOLDERSPLAN OF DISTRIBUTIONLEGAL MATTERSEXPERTSENFORCEMENT OF JUDGMENTSWHERE YOU CAN FIND MORE INFORMATIONINFORMATION INCORPORATED BY REFERENCE Table of Contents ABOUT THIS PROSPECTUS Before buying any of the common shares that the selling shareholders are offering, you should carefully read both thisprospectus and any prospectus supplement with all of the information incorporated by reference in this prospectus, as wellas the additional information described under the heading “Where You Can Find More Information” and “InformationIncorporated by Reference.” These documents contain important information that you should consider when making yourinvestment decision. We have filed or incorporated by reference exhibits to the registration statement of which thisprospectus forms a part. You should read the exhibits carefully for provisions that may be important to you. To the extent there is a conflict between the information contained in this prospectus, on the one hand, and the informationcontained in any prospectus supplement or in any document incorporated by reference in this prospectus, on the otherhand, you should rely on the information in this prospectus, provided that if any statement in one of these documents isinconsistent with a statement in another document having a later date—for example, a prospectus supplement or adocument incorporated by reference in this prospectus—the statement in the document having the later date modifies orsupersedes the earlier statement. The information contained in this prospectus, any applicable prospectus supplement or any document incorporated byreference in this prospectus is accurate only as of their respective dates, regardless of the time of delivery of thisprospectus, any applicable prospectus supplement or the documents incorporated by reference in this prospectus or thesale of any common shares. Our business, financial condition, results of operations and prospects may have changedmaterially since those dates. We and the selling shareholders have not authorized anyone to provide any information or to make any representationsother than as contained in this prospectus, any amendment or supplement to this prospectus, or any free writingprospectus prepared by or on behalf of us or to which we may have referred you. We and the selling shareholders take noresponsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Thisprospectus does not constitute an offer to sell or the solicitation of an offer to buy any securities other than the commonshares described in this prospectus or an offer to sell or the solicitation of an offer to buy