Ordinary Shares, par value $0.0001 per share

BeOne Medicines Ltd. (f/k/a BeiGene Ltd.)

c/o BeOne Medicines I GmbH, Basel, V8, 4051

The disclosures in the Reporting Persons pages and in Item 4 are incorporated by reference herein. (a) and (b) Items 7 through 11 and 13 of each of the cover pages of this Amendment No. 12 are incorporated herein by reference. The Ordinary Shares reported for each of the Adviser and the Adviser GP include 114,387,689 of the Ordinary Shares the Issuer reported that are beneficially owned through 8,799,053 ADS. The Ordinary Shares reported for Julian C. Baker include 114,387,689 of the Ordinary Shares the Issuer reported that are beneficially owned through 8,799,053 ADS, 135,434 Ordinary Shares reported that are beneficially owned through 10,418 ADS directly held by Julian C. Baker, 175,708 Ordinary Shares reported that are beneficially owned through 13,516 ADS directly held by entities affiliated with Julian C. Baker and 144,508 Ordinary Shares reported that are beneficially owned through 11,116 ADS held by FBB3. The Ordinary Shares reported for Felix J. Baker include 114,387,689 of the Ordinary Shares the Issuer reported that are beneficially owned through 8,799,053 ADS, 135,434 Ordinary Shares reported that are beneficially owned through 10,418 ADS directly held by Felix J. Baker, 175,708 Ordinary Shares reported that are beneficially owned through 13,516 ADS directly held by entities affiliated with Felix J. Baker and 144,508 Ordinary Shares reported that are beneficially owned through 11,116 ADS directly held by FBB3. The Ordinary Shares reported for FBB3 include 144,508 of the Ordinary Shares the Issuer reported that are beneficially owned through 11,116 ADS. The percentage of beneficial ownership for each of the Reporting Persons reported herein, with the exception of FBB3 is based on 1,442,259,810 Ordinary Shares outstanding as of February 13, 2026 as reported in the Issuer's Form 10-K filed with the Securities and Exchange Commission ("SEC") on February 26, 2026 plus 10,985 Ordinary Shares underlying 10,985 RSUs vesting in 60 days which were received by each of Michael Goller and Ranjeev Krishana, full-time employees of the Adviser, as compensation for their service on the Board and 463,437 Ordinary Shares underlying 463,437 Share Options which were received by each of Michael Goller and Ranjeev Krishana, as compensation for their service on the Board. The percentage of beneficial ownership for FBB3 reported herein is based on 1,442,259,810 Ordinary Shares outstanding as of February 13, 2026 as reported in the Issuer's Form 10-K filed with the SEC on February 26, 2026.

Set forth in Exhibit 99.1 is the aggregate number of Ordinary Shares of the Issuer directly held by the Funds, 114,387,689 of which are directly held by the Funds through 8,799,053 ADS, along with the percentage of the Issuer's outstanding Ordinary Shares such holdings represent. Julian C. Baker and Felix J. Baker each beneficially own 135,435 Ordinary Shares, 135,434 of which are held in the form of ADS. Entities affiliated with Julian C. Baker and Felix J. Baker each beneficially own 175,708 Ordinary Shares, 175,708 of which are held in the form of ADS. FBB3 holds 144,517 Ordinary Shares, 144,508 of which are held in the form of ADS. Michael Goller and Ranjeev Krishana have served on the Board since April 21, 2015 and October 7, 2014, respectively. Michael Goller and Ranjeev Krishana currently serve on the Board as representatives of the Funds. Michael Goller and Ranjeev Krishana each hold 463,437 Share Options received in connection with their service on the Board which are exercisable within 60 days from the date of this Amendment No. 12. Michael Goller and Ranjeev Krishana each hold 63,037 Ordinary Shares which were received upon the vesting of RSUs in connection with their service on the Board. Michael Goller and Ranjeev Krishana each hold 10,985 RSUs which were granted on May 21, 2025 in connection with their service on the Board and which vest on the earlier to occur of the first anniversary of the grant date or the date of the next annual general meeting of the Issuer. The policy of the Funds and the Adviser does not permit managing members of the Adviser GP or full-time employees of the Adviser to receive compensation for serving as directors of the Issuer, and the Funds are instead entitled to the pecuniary interest in any compensation received for their service. The Adviser has voting and investment power over the RSUs, Share Options and Ordinary Shares underlying such Share Options and Ordinary Shares received from the exercise of Share Options by Michael Goller and Ranjeev Krishana as director's compensation. The Adviser GP, and Felix J. Baker and Julian C. Baker as managing members of the Adviser GP, may be deemed to have the power to vote or direct the vote of and the power to dispose or direct the disposition of the Share Options, Ordinary Shares received from the exercise of Share Options and Ordinary Shares underlying such Share Options held by Michael Goller and Ranjeev Krishana as director's compensation. The Adviser GP, Felix J. Baker and Julian C. Baker as managing members of the Adviser GP, and the Adviser may be deemed to be beneficial owners of securities of the Issuer directly held by the Funds. Julian C. Baker and Felix J. Baker are also the sole managers of FBB3 and by policy they do not transact in or vote the securities of the Issuer held by FBB3.

The information set forth in Item 4 is hereby incorporated by reference into this Item 5(c). Except as disclosed herein, none of the Reporting Persons or their affiliates has effected any other transactions in securities of the Issuer during the past 60 days.

(d) Certain securities of the Issuer are held directly by 667, a limited partnership the sole general partner of which is Baker Biotech Capital, L.P., a limited partnership the sole general partner of which is Baker Biotech Capital (GP), LLC. Julian C. Baker and Felix J. Baker are the managing members of Baker Biotech Capital (GP), LLC. Certain securities of the Issuer are held directly by Life Sciences, a limited partnership the sole general partner of which is Baker Brothers Life Sciences Capital, L.P., a limited partnership the sole general partner of which is Baker Brothers Life Sciences Capital (GP), LLC. Julian C. Baker and Felix J. Baker are the managing members of Baker Brothers Life Sciences Capital (GP), LLC.

(e) Not applicable.