Proxy Statement Pursuant to Section 14(a) of the
Securities Exchange Act of 1934

Important Notice Regarding the Internet Availability of Proxy Materials for the 2026 Annual General Meeting of Shareholders to be held

This communication is not a form for voting and presents only an overview of the more complete proxy materials that are available to you on the Internet. We encourage you to access and review all of the important information contained in the proxy materials before voting.

The proxy statement, proxy card and our annual report on Form 10-K for the fiscal year ended December 31, 2025 are available online at https://ir.beonemedicines.com/filings-financials/shareholder-meeting-materials.

If you want to receive a paper or e-mail copy of these documents, you must request one. There is no charge to you for requesting a copy. Please make your request for a copy as instructed below on or before June 1, 2026 to facilitate timely delivery.

Important information regarding the Internet availability of the Company’s proxy materials, instructions for accessing your proxy materials, voting instructions and instructions for requesting paper or e-mail copies of your proxy materials are provided on the reverse side of this notice.

Persons who hold shares indirectly through a brokerage firm, bank or other financial institution, including ADS holders, must contact their brokerage firm, bank or other financial institution for voting purposes.

To the Shareholders of BeOne Medicines Ltd.:

The 2026 Annual General Meeting of Shareholders of BeOne Medicines Ltd. (the “Company”) will be held on June 11, 2026, at 3:30 p.m. local time at the offices of Homburger AG, at Prime Tower, Hardstrasse 201, CH-8005 Zürich, Switzerland to consider and vote on the following matters:

to approve the audited Swiss statutory standalone financial statements and the audited Swiss statutory consolidated financial statements of the Company for fiscal year 2025;

to approve the appropriation of the accumulated loss for fiscal year 2025;

to discharge the members of the Board of Directors and the Executive Management Team from liability for activities during the applicable period under Swiss law;

(a) to re-elect Dr. Olivier Brandicourt to serve as a director for a term extending until completion of the 2027 annual general meeting;

(b) to re-elect Dr. Margaret Dugan to serve as a director for a term extending until completion of the 2027 annual general meeting;

(c) to re-elect Mr. Anthony C. Hooper to serve as a director for a term extending until completion of the 2027 annual general meeting;

(d) to re-elect Mr. John V. Oyler to serve as a director for a term extending until completion of the 2027 annual general meeting;

(e) to re-elect Dr. Alessandro Riva to serve as a director for a term extending until completion of the 2027 annual general meeting;

(f) to re-elect Ms. Shalini Sharp to serve as a director for a term extending until completion of the 2027 annual general meeting;

(g) to re-elect Dr. Xiaodong Wang to serve as a director for a term extending until completion of the 2027 annual general meeting;

(h) to elect Dr. Felix J. Baker to serve as a director for a term extending until completion of the 2027 annual general meeting;

(i) to elect Ms. Elizabeth F. Mooney to serve as a director for a term extending until completion of the 2027 annual general meeting;

(j) to elect Dr. Charles L. Sawyers to serve as a director for a term extending until completion of the 2027 annual general meeting;

to re-elect Mr. John V. Oyler as Chairman of the Board of Directors for a term extending until completion of the 2027 annual general meeting;

(a) to re-elect Dr. Margaret Dugan to serve as a member of the Compensation Committee of the Board of Directors for a term extending until completion of the 2027 annual general meeting;

(b) to elect Ms. Elizabeth F. Mooney to serve as a member of the Compensation Committee of the Board of Directors for a term extending until completion of the 2027 annual general meeting;

to elect the law firm of Schweiger Advokatur/Notariat, Dammstrasse 19, 6300 Zug, Switzerland, as the Independent Voting Representative for a term extending until completion of the 2027 annual general meeting;

to ratify the appointment of Ernst & Young LLP, Ernst & Young and Ernst & Young Hua Ming LLP as the Company’s independent auditors for the fiscal year ending December 31, 2026 and to re-elect Ernst & Young AG as the Company’s statutory auditor for the fiscal year ending December 31, 2026;

to authorize the Board of Directors to fix the auditors’ compensation for the fiscal year ending December 31, 2026;

10.

to approve, on an advisory basis, the compensation of our Named Executive Officers, as disclosed in the Proxy Statement, for the fiscal year ended December 31, 2025;

11.

to approve the maximum aggregate compensation of the Board of Directors under Swiss law for the applicable period;

12.

to approve the maximum aggregate compensation of the Executive Management Team under Swiss law for fiscal year 2027;

13.

to approve, on an advisory basis, the Swiss Statutory Compensation Report for the fiscal year ended December 31, 2025;

14.

to approve, on an advisory basis, the Swiss Statutory Non-Financial Matters Report for the fiscal year ended December 31, 2025;

15.

(a) to approve an amendment and restatement of the Company’s 2016 Share Option and Incentive Plan;

(b) to approve the consultant sublimit set out in the Company’s amended and restated 2016 Share Option and Incentive Plan;

16.

to approve an amendment and restatement of the Company’s 2018 Employee Share Purchase Plan;

17.

to approve, within the parameters of the HK Listing Rules, the granting of a share issue mandate to the Board of Directors to issue, allot or deal with unissued ordinary shares and/or ADSs (including any sale or transfer of treasury shares out of treasury) not exceeding 20% of the total number of issued shares of the Company (excluding treasury shares) as of the date of passing of such resolution up to the next annual general meeting of shareholders of the Company, subject to the conditions described in the Proxy Statement;

18.

to approve, within the parameters of the HK Listing Rules, the granting of a share repurchase mandate to the Board of Directors to repurchase an amount of ordinary shares (excluding the RMB shares) and/or ADSs, not exceeding 10% of the total number of issued ordinary shares (excluding RMB shares and treasury shares) of the Company as of the date of passing of such resolution up to the next annual general meeting of shareholders of the Company, subject to the conditions described in the Proxy Statement;

19.

to authorize the Company and its underwriters, in their sole discretion, to allocate to Amgen Inc. (“Amgen”) up to a maximum amount of shares in order to maintain the same shareholding percentage of Amgen (based on the then-outstanding share capital of the Company) before and after the allocation of the corresponding securities issued pursuant to an offering conducted pursuant to the general mandate set forth above for a period of five years, which period will be subject to an extension on a rolling basis each year, conditional on the approval of the shareholders who are not Amgen, subject to the conditions described in the Proxy Statement; and

20.

to approve the adjournment of the Annual Meeting by the chairman, if necessary, to solicit additional proxies if there are insufficient votes at the time of the Annual Meeting to approve any of the proposals described above.

The Board of Directors recommends you vote FOR each director nominee and FOR each of the other resolutions.

The Securities and Exchange Commission rules permit us to make our proxy materials available to our shareholders via the Internet.

Materials for this meeting may be requested by one of the following methods:

	To view your proxy materials online, please go to https://ir.beonemedicines.com/filings-financials/shareholder-meeting-materials.

	To request proxy materials by telephone, please call +1 (877) 828-5568.

	To request proxy materials by email, please send an email to ir@beonemed.com.

The 2026 Annual General Meeting of Shareholders (the “Annual Meeting”) of BeOne Medicines Ltd. (the “Company”) will be held on June 11, 2026, at 3:30 p.m. local time at the offices of Homburger AG, at Prime Tower, Hardstrasse 201, CH-8005 Zürich, Switzerland. Only persons holding shares as of May 22, 2026 can attend and vote at the Annual Meeting. Instructions on how to attend and vote your shares are contained in the proxy statement in the section titled “General Information.”

The FOLLOWING PROXY MATERIALS ARE AVAILABLE TO YOU FOR REVIEW AT: HTTPS://IR.BEONEMEDICINES.COM/FILINGS-FINANCIALS/SHAREHOLDER-MEETING-MATERIALS.

¨	Preliminary Proxy Statement

¨	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

¨	Definitive Proxy Statement

x	Definitive Additional Materials

¨	Soliciting Material Pursuant to §240.14a-12

x	No fee required.

¨	Fee paid previously with preliminary materials.

¨	Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.