Opérations des initiés

Disposition pursuant to a tender of shares in a change of control transaction

• F1 This Form 4 is filed jointly by Biotechnology Value Fund, L.P. (BVF), Biotechnology Value Fund II, L.P. (BVF2), Biotechnology Value Trading Fund OS LP (Trading Fund OS), BVF Partners OS Ltd. (Partners OS), BVF I GP LLC (BVF GP), BVF II GP LLC (BVF2 GP), BVF GP Holdings LLC (BVF GPH), BVF Partners L.P. (Partners), BVF Inc. and Mark N. Lampert (collectively, the Reporting Persons). Each of the Reporting Persons is a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.
• F2 This Form 4 reports securities disposed of pursuant to an Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among the Issuer, Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo), pursuant to which, among other things, the Parent acquired all of the outstanding shares of the common stock of the Issuer, effective July 14, 2026 (the Merger).
• F7 The Reporting Persons received the following in exchange for each share of the Issuer's common stock disposed of in connection with the Merger: $39.00 in cash per share of common stock and an amount of contingent value rights per share of common stock for potential cash payments.
• F3 Securities owned directly by BVF. As the general partner of BVF, BVF GP may be deemed to beneficially own the securities owned directly by BVF. As the sole member of BVF GP, BVF GPH may be deemed to beneficially own the securities owned directly by BVF. As the investment manager of BVF, Partners may be deemed to beneficially own the securities owned directly by BVF. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by BVF. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by BVF.

Disposition pursuant to a tender of shares in a change of control transaction

• F1 This Form 4 is filed jointly by Biotechnology Value Fund, L.P. (BVF), Biotechnology Value Fund II, L.P. (BVF2), Biotechnology Value Trading Fund OS LP (Trading Fund OS), BVF Partners OS Ltd. (Partners OS), BVF I GP LLC (BVF GP), BVF II GP LLC (BVF2 GP), BVF GP Holdings LLC (BVF GPH), BVF Partners L.P. (Partners), BVF Inc. and Mark N. Lampert (collectively, the Reporting Persons). Each of the Reporting Persons is a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.
• F2 This Form 4 reports securities disposed of pursuant to an Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among the Issuer, Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo), pursuant to which, among other things, the Parent acquired all of the outstanding shares of the common stock of the Issuer, effective July 14, 2026 (the Merger).
• F7 The Reporting Persons received the following in exchange for each share of the Issuer's common stock disposed of in connection with the Merger: $39.00 in cash per share of common stock and an amount of contingent value rights per share of common stock for potential cash payments.
• F4 Securities owned directly by BVF2. As the general partner of BVF2, BVF2 GP may be deemed to beneficially own the securities owned directly by BVF2. As the sole member of BVF2 GP, BVF GPH may be deemed to beneficially own the securities owned directly by BVF2. As the investment manager of BVF2, Partners may be deemed to beneficially own the securities owned directly by BVF2. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by BVF2. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by BVF2.

Disposition pursuant to a tender of shares in a change of control transaction

• F1 This Form 4 is filed jointly by Biotechnology Value Fund, L.P. (BVF), Biotechnology Value Fund II, L.P. (BVF2), Biotechnology Value Trading Fund OS LP (Trading Fund OS), BVF Partners OS Ltd. (Partners OS), BVF I GP LLC (BVF GP), BVF II GP LLC (BVF2 GP), BVF GP Holdings LLC (BVF GPH), BVF Partners L.P. (Partners), BVF Inc. and Mark N. Lampert (collectively, the Reporting Persons). Each of the Reporting Persons is a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.
• F2 This Form 4 reports securities disposed of pursuant to an Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among the Issuer, Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo), pursuant to which, among other things, the Parent acquired all of the outstanding shares of the common stock of the Issuer, effective July 14, 2026 (the Merger).
• F7 The Reporting Persons received the following in exchange for each share of the Issuer's common stock disposed of in connection with the Merger: $39.00 in cash per share of common stock and an amount of contingent value rights per share of common stock for potential cash payments.
• F5 Securities owned directly by Trading Fund OS. As the general partner of Trading Fund OS, Partners OS may be deemed to beneficially own the securities owned directly by Trading Fund OS. As the investment manager of Trading Fund OS and the sole member of Partners OS, Partners may be deemed to beneficially own the securities owned directly by Trading Fund OS. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by Trading Fund OS. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by Trading Fund OS.

Disposition pursuant to a tender of shares in a change of control transaction

• F1 This Form 4 is filed jointly by Biotechnology Value Fund, L.P. (BVF), Biotechnology Value Fund II, L.P. (BVF2), Biotechnology Value Trading Fund OS LP (Trading Fund OS), BVF Partners OS Ltd. (Partners OS), BVF I GP LLC (BVF GP), BVF II GP LLC (BVF2 GP), BVF GP Holdings LLC (BVF GPH), BVF Partners L.P. (Partners), BVF Inc. and Mark N. Lampert (collectively, the Reporting Persons). Each of the Reporting Persons is a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.
• F2 This Form 4 reports securities disposed of pursuant to an Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among the Issuer, Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo), pursuant to which, among other things, the Parent acquired all of the outstanding shares of the common stock of the Issuer, effective July 14, 2026 (the Merger).
• F7 The Reporting Persons received the following in exchange for each share of the Issuer's common stock disposed of in connection with the Merger: $39.00 in cash per share of common stock and an amount of contingent value rights per share of common stock for potential cash payments.
• F6 Securities held in certain Partners managed accounts (the Partners Managed Accounts). Partners, as the investment manager of the Partners Managed Accounts, may be deemed to beneficially own the securities held by the Partners Managed Accounts. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities held by the Partners Managed Accounts. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities held by the Partners Managed Accounts.

Other acquisition or disposition (describe transaction)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F2 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).
• F3 At the Effective Time, pursuant to the Merger Agreement, each outstanding restricted stock unit (RSU) became fully vested and cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required withholding tax, equal to the product of (i) the number of Shares subject to such RSU and (ii) the Closing Amount, plus (B) one CVR for each Share subject to such RSU.

Other acquisition or disposition (describe transaction)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F2 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 Prior to the Effective Time, pursuant to the Merger Agreement, each issued and outstanding share of 8.375% Series B Cumulative Perpetual Preferred Stock, par value $0.05 per share, of the Issuer (including the Depositary Shares) was redeemed by the Issuer in accordance with the terms of the certificate of designation governing such stock, including payment of all accrued and unpaid dividends thereon through the date of such redemption.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F7 Immediately prior to the Effective Time, pursuant to the Merger Agreement, each outstanding performance stock unit award (PSU) automatically converted into and was substituted with a restricted stock unit award (each, a Converted PSU) with respect to a number of Shares equal to either (x) for each PSU granted on or after March 1, 2026, the excess of (A) 100% of the Target Shares (as the term Target Shares is defined and set forth in the applicable award agreement governing such PSU) underlying such PSU over (B) the number of Target Shares as to which, as of immediately prior to the Effective Time, the Performance-Requirement has been achieved, or (y) for each PSU granted prior to March 1, 2026, the excess of (A) the percentage of the Target Shares underlying such PSU as to which the Performance-Requirement would be satisfied if the Closing Price (as defined in the applicable award agreement governing such PSU) were equal to the Closing Amount over
• F8 (Continued from footnote 7) (B) the number of Target Shares as to which, as of immediately prior to the Effective Time, the Performance-Requirement has been achieved. Immediately prior to the Effective Time, each Converted PSU was automatically cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required tax withholding, equal to the product of (i) the number of Shares subject to such Converted PSU and (ii) the Closing Amount, and (B) one CVR for each Share subject to such Converted PSU.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F7 Immediately prior to the Effective Time, pursuant to the Merger Agreement, each outstanding performance stock unit award (PSU) automatically converted into and was substituted with a restricted stock unit award (each, a Converted PSU) with respect to a number of Shares equal to either (x) for each PSU granted on or after March 1, 2026, the excess of (A) 100% of the Target Shares (as the term Target Shares is defined and set forth in the applicable award agreement governing such PSU) underlying such PSU over (B) the number of Target Shares as to which, as of immediately prior to the Effective Time, the Performance-Requirement has been achieved, or (y) for each PSU granted prior to March 1, 2026, the excess of (A) the percentage of the Target Shares underlying such PSU as to which the Performance-Requirement would be satisfied if the Closing Price (as defined in the applicable award agreement governing such PSU) were equal to the Closing Amount over
• F8 (Continued from footnote 7) (B) the number of Target Shares as to which, as of immediately prior to the Effective Time, the Performance-Requirement has been achieved. Immediately prior to the Effective Time, each Converted PSU was automatically cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required tax withholding, equal to the product of (i) the number of Shares subject to such Converted PSU and (ii) the Closing Amount, and (B) one CVR for each Share subject to such Converted PSU.

Other acquisition or disposition (describe transaction)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F2 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).
• F3 At the Effective Time, pursuant to the Merger Agreement, each outstanding restricted stock unit (RSU) became fully vested and cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required withholding tax, equal to the product of (i) the number of Shares subject to such RSU and (ii) the Closing Amount, plus (B) one CVR for each Share subject to such RSU.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Other acquisition or disposition (describe transaction)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F2 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).
• F3 At the Effective Time, pursuant to the Merger Agreement, each outstanding restricted stock unit (RSU) became fully vested and cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required withholding tax, equal to the product of (i) the number of Shares subject to such RSU and (ii) the Closing Amount, plus (B) one CVR for each Share subject to such RSU.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F5 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Other acquisition or disposition (describe transaction)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F2 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).
• F3 At the Effective Time, pursuant to the Merger Agreement, each outstanding restricted stock unit (RSU) became fully vested and cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required withholding tax, equal to the product of (i) the number of Shares subject to such RSU and (ii) the Closing Amount, plus (B) one CVR for each Share subject to such RSU.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 Prior to the Effective Time, pursuant to the Merger Agreement, each issued and outstanding share of 8.625% Series A Cumulative Perpetual Preferred Stock, par value $0.05 per share, of the Issuer was redeemed by the Issuer in accordance with the terms of the certificate of designation governing such stock, including payment of all accrued and unpaid dividends thereon through the date of such redemption.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 Prior to the Effective Time, pursuant to the Merger Agreement, each issued and outstanding share of 8.375% Series B Cumulative Perpetual Preferred Stock, par value $0.05 per share, of the Issuer (including the Depositary Shares) was redeemed by the Issuer in accordance with the terms of the certificate of designation governing such stock, including payment of all accrued and unpaid dividends thereon through the date of such redemption.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F7 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Other acquisition or disposition (describe transaction)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F2 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).
• F3 At the Effective Time, pursuant to the Merger Agreement, each outstanding restricted stock unit (RSU) became fully vested and cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required withholding tax, equal to the product of (i) the number of Shares subject to such RSU and (ii) the Closing Amount, plus (B) one CVR for each Share subject to such RSU.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F4 Prior to the Effective Time, pursuant to the Merger Agreement, each issued and outstanding share of 8.625% Series A Cumulative Perpetual Preferred Stock, par value $0.05 per share, of the Issuer was redeemed by the Issuer in accordance with the terms of the certificate of designation governing such stock, including payment of all accrued and unpaid dividends thereon through the date of such redemption.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F1 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 At the Effective Time, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, a Company Stock Option) that had an exercise price per Share that was less than the sum of the Closing Amount and the fair market value of one CVR (each, a Terminating Company Stock Option) became fully vested and was cancelled, and in exchange therefor, the holder received (i) an amount in cash, without interest, and subject to deduction for any required withholding taxes, equal to the product of (A) the excess of the Closing Amount over the exercise price per Share with respect to such Terminating Company Stock Option and (B) the number of Shares subject to such Terminating Company Stock Option, plus (ii) one CVR with respect to each Share subject to such Terminating Company Stock Option.
• F6 As of immediately prior to the Effective Time, each Company Stock Option that did not constitute a Terminating Company Stock Option was cancelled and no consideration was delivered in exchange therefor.

Other acquisition or disposition (describe transaction)

• F1 Includes 804 shares acquired under the ESPP Plan on May 31, 2026.
• F2 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F3 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).
• F4 At the Effective Time, pursuant to the Merger Agreement, each outstanding restricted stock unit (RSU) became fully vested and cancelled and converted into the right to receive (A) an amount in cash, without interest, and subject to deduction for any required withholding tax, equal to the product of (i) the number of Shares subject to such RSU and (ii) the Closing Amount, plus (B) one CVR for each Share subject to such RSU.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F2 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F5 Prior to the Effective Time, pursuant to the Merger Agreement, each issued and outstanding share of 8.625% Series A Cumulative Perpetual Preferred Stock, par value $0.05 per share, of the Issuer was redeemed by the Issuer in accordance with the terms of the certificate of designation governing such stock, including payment of all accrued and unpaid dividends thereon through the date of such redemption.

Disposition to the issuer of issuer equity securities pursuant to Rule 16b-3(e)

• F2 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F6 Prior to the Effective Time, pursuant to the Merger Agreement, each issued and outstanding share of 8.375% Series B Cumulative Perpetual Preferred Stock, par value $0.05 per share, of the Issuer (including the Depositary Shares) was redeemed by the Issuer in accordance with the terms of the certificate of designation governing such stock, including payment of all accrued and unpaid dividends thereon through the date of such redemption.

Other acquisition or disposition (describe transaction)

• F2 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F3 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).

Other acquisition or disposition (describe transaction)

• F2 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F3 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).

Other acquisition or disposition (describe transaction)

• F2 Disposed of pursuant to the Agreement and Plan of Merger, dated April 27, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger on May 16, 2026 (as amended, the Merger Agreement), by and among XOMA Royalty Corporation (the Issuer), Ligand Pharmaceuticals Incorporated (Parent), Flex Merger Sub, Inc., a wholly-owned subsidiary of Parent (Merger Sub), and XOMA Royalty Holdings Corporation (HoldCo). Pursuant to the Merger Agreement, on July 14, 2026, the Issuer effected a holding company reorganization, and Merger Sub merged with and into HoldCo (the Merger), with HoldCo surviving the Merger as a wholly-owned subsidiary of Parent. Unless context otherwise requires, all references in this Form 4 to the Issuer refer to HoldCo, which assumed all obligations of the Issuer under the Merger Agreement.
• F3 At the time the Merger became effective (the Effective Time), pursuant to the Merger Agreement, each issued and outstanding share of common stock, par value $0.0075 per share, of the Issuer (the Shares) (other than certain Shares cancelled pursuant to the Merger Agreement and Dissenting Shares (as defined in the Merger Agreement)) automatically converted into the right to receive (i) $39.00 per Share in cash, without interest, and subject to deduction for any required withholding tax (the Closing Amount), plus (ii) an amount of contingent value rights (each, a CVR) representing a right to receive certain contingent payments subject to and in accordance with the terms of the CVR Agreement (as defined in the Merger Agreement) (the Closing Amount plus CVR, the Merger Consideration).