MREO

SEC source: 0000950170-24-106968 · ownership.xml · nonDerivative · entry 4

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 50,475

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F5 · shares: The Reporting Person sold a total of 124,037 ADSs solely to pay tax obligations, including tax withholding obligations related to the exercise of stock options described in the Form 4 filed on September 13, 2024.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.01 to $4.43, inclusive.

SEC source: 0000950170-24-106968 · ownership.xml · nonDerivative · entry 3

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 134,483

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the 'Plan'), occurring on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.01 to $4.43, inclusive.

SEC source: 0000950170-24-106972 · ownership.xml · nonDerivative · entry 2

Sermon Charles · CIK 0001687318 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 219,061

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F5 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.01 to $4.43, inclusive.

SEC source: 0000950170-24-106976 · ownership.xml · nonDerivative · entry 2

Scots-Knight Denise · CIK 0001297000 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 808,921

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F5 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.01 to $4.43, inclusive.

F6 · balance_after: Includes 1,200 ADSs jointly owned by Reporting person and her spouse.

SEC source: 0000950170-24-106974 · ownership.xml · nonDerivative · entry 2

Lewicki John A. · CIK 0001553352 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 78,630

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.01 to $4.43, inclusive.

SEC source: 0000950170-24-106970 · ownership.xml · nonDerivative · entry 1

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 108,443

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.37 to $4.62, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

SEC source: 0000950170-24-106968 · ownership.xml · nonDerivative · entry 2

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 150,787

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F5 · shares: The Reporting Person sold a total of 124,037 ADSs solely to pay tax obligations, including tax withholding obligations related to the exercise of stock options described in the Form 4 filed on September 13, 2024.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.37 to $4.62, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

SEC source: 0000950170-24-106968 · ownership.xml · nonDerivative · entry 1

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 190,816

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the 'Plan'), occurring on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.37 to $4.62, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

F6 · balance_after: The total amount of securities beneficially owned on the reporting person's Form 4 filed on September 13, 2024 has been reduced by 44,296, which reflects ADSs withheld by the Issuer in connection with the net settlement of the stock option exercise on September 11, 2024 and inadvertently omitted from the September 13, 2024 filing. Such withholding is exempt from Section 16(b) pursuant to Rule 16b-3.

SEC source: 0000950170-24-106972 · ownership.xml · nonDerivative · entry 1

Sermon Charles · CIK 0001687318 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 240,007

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · security: Reporting Person also beneficially owns 4 ordinary shares, nominal value of GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.37 to $4.62, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (4) and (5) to this Form 4.

SEC source: 0000950170-24-106976 · ownership.xml · nonDerivative · entry 1

Scots-Knight Denise · CIK 0001297000 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 868,967

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · security: Reporting Person also beneficially owns 4 ordinary shares, nominal value of GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.37 to $4.62, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (4) and (5) to this Form 4.

F6 · balance_after: Includes 1,200 ADSs jointly owned by Reporting person and her spouse.

SEC source: 0000950170-24-106974 · ownership.xml · nonDerivative · entry 1

Lewicki John A. · CIK 0001553352 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 89,567

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.37 to $4.62, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

SEC source: 0000950170-24-106419 · ownership.xml · derivative · entry 2

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 60,000 shares

Expires 2025-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106419 · ownership.xml · nonDerivative · entry 1

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 117,571

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents performance-based restricted stock unit earned under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024 based on satisfaction of ADS price threshold values over a two year performance period.

SEC source: 0000950170-24-106413 · ownership.xml · derivative · entry 6

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 75,000 shares

Expires 2033-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_date: 240,000 options were issued on 01/25/2023 and 25% of the shares underlying this award became exercisable on January 25, 2024, with the remainder vesting in equal monthly installments thereafter.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106413 · ownership.xml · derivative · entry 5

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 93,333 shares

Expires 2032-01-14

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · derivative.exercise_date: 160,000 options were issued on 01/14/2022 and 25% of the shares underlying this award became exercisable on January 14, 2023, with the remainder vesting in equal monthly installments thereafter.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106413 · ownership.xml · derivative · entry 4

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 40,000 shares

Expires 2025-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106413 · ownership.xml · nonDerivative · entry 3

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 242,881

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106413 · ownership.xml · nonDerivative · entry 2

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 167,881

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106413 · ownership.xml · nonDerivative · entry 1

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 74,548

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents performance-based restricted stock unit earned under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024 based on satisfaction of ADS price threshold values over a two year performance period.

SEC source: 0000950170-24-106426 · ownership.xml · derivative · entry 2

Sermon Charles · CIK 0001687318 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 65,600 shares

Expires 2025-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106426 · ownership.xml · nonDerivative · entry 1

Sermon Charles · CIK 0001687318 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 249,987

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F3 · security: Reporting Person also beneficially owns 4 ordinary shares, nominal value of GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents performance-based restricted stock unit earned under the Issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024 based on satisfaction of ADS price threshold values over a two year performance period.

SEC source: 0000950170-24-106417 · ownership.xml · derivative · entry 2

Scots-Knight Denise · CIK 0001297000 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 188,060 shares

Expires 2025-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106417 · ownership.xml · nonDerivative · entry 1

Scots-Knight Denise · CIK 0001297000 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 897,578

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F3 · security: Reporting Person also beneficially owns 4 ordinary shares, nominal value of GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents performance-based restricted stock unit earned under the Issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024 based on satisfaction of ADS price threshold values over a two year performance period.

F4 · balance_after: Includes 1,200 ADSs jointly owned by Reporting person and her spouse.

SEC source: 0000950170-24-106418 · ownership.xml · derivative · entry 3

Lewicki John A. · CIK 0001553352 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 46,000 shares

Expires 2025-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-106418 · ownership.xml · nonDerivative · entry 1

Lewicki John A. · CIK 0001553352 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 94,779

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents performance-based restricted stock unit earned under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on September 11, 2024 based on satisfaction of ADS price threshold values over a two year performance period.

SEC source: 0000950170-24-100281 · ownership.xml · derivative · entry 13

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 30,000

Underlying: American Depository Shares · 15,000 shares

Expires 2034-02-08

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_date: Vests in substantially equal monthly installments over a one year period from the February 8, 2024 grant date. As of June 8, 2024, 15,000 Share Options have vested.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · derivative · entry 12

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 55,000 shares

Expires 2033-02-01

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F8 · derivative.exercise_date: Vested in substantially equal monthly installments over a one year period from the February 1, 2023 grant date.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · derivative · entry 11

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 55,000 shares

Expires 2032-02-01

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F7 · derivative.exercise_date: Vested in substantially equal monthly installments over a one year period from the February 1, 2022 grant date.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · derivative · entry 10

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 31,500 shares

Expires 2031-02-01

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F6 · derivative.exercise_date: Vested in substantially equal monthly installments over a one year period from the February 1, 2021 grant date.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · derivative · entry 9

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 11,000 shares

Expires 2030-02-20

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F5 · derivative.exercise_date: Vested in substantially equal monthly installments over a one year period from the February 20, 2020 grant date.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · derivative · entry 8

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: American Depository Shares · 5,500 shares

Expires 2029-07-23

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_date: Vested in substantially equal monthly installments over a one year period from the July 23, 2019 grant date.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 7

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

F2 · shares: Sale is due to fund administration reasons.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $4.360 to $4.495, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnote (3) to this Form

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 6

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 105,244

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 5

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 103,173

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 4

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 59,688

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 3

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,735

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 2

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,317

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-100281 · ownership.xml · nonDerivative · entry 1

PAKIANATHAN DEEPIKA · CIK 0001270734 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,825

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares of the Issuer.

SEC source: 0000950170-24-078467 · ownership.xml · nonDerivative · entry 2

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 57,571

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.28 to $3.51, inclusive.

SEC source: 0000950170-24-078462 · ownership.xml · nonDerivative · entry 2

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,548

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.28 to $3.51, inclusive.

SEC source: 0000950170-24-078469 · ownership.xml · nonDerivative · entry 2

Sermon Charles · CIK 0001687318 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 184,387

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F5 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.28 to $3.51, inclusive.

SEC source: 0000950170-24-078465 · ownership.xml · nonDerivative · entry 2

Scots-Knight Denise · CIK 0001297000 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 709,518

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F5 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.28 to $3.51, inclusive.

F6 · balance_after: Includes 1,200 ADSs jointly owned by Reporting person and her spouse.

SEC source: 0000950170-24-078468 · ownership.xml · nonDerivative · entry 2

Lewicki John A. · CIK 0001553352 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 48,779

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.28 to $3.51, inclusive.

SEC source: 0000950170-24-078467 · ownership.xml · nonDerivative · entry 1

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 87,010

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.60 to $3.805, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

SEC source: 0000950170-24-078462 · ownership.xml · nonDerivative · entry 1

Hughes-Wilson Alexandra · CIK 0002005875 · See Remarks

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 57,516

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.60 to $3.805, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

SEC source: 0000950170-24-078469 · ownership.xml · nonDerivative · entry 1

Sermon Charles · CIK 0001687318 · General Counsel

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 216,574

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · security: Reporting Person also beneficially owns 4 ordinary shares, nominal value of GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.60 to $3.805, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (4) and (5) to this Form 4.

SEC source: 0000950170-24-078465 · ownership.xml · nonDerivative · entry 1

Scots-Knight Denise · CIK 0001297000 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 801,791

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · security: Reporting Person also beneficially owns 4 ordinary shares, nominal value of GBP 0.003 per ordinary share, of the Issuer.

F3 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F4 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.60 to $3.805, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (4) and (5) to this Form 4.

F6 · balance_after: Includes 1,200 ADSs jointly owned by Reporting person and her spouse.

SEC source: 0000950170-24-078468 · ownership.xml · nonDerivative · entry 1

Lewicki John A. · CIK 0001553352 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 65,587

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents the number of ADSs required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Performance-based restricted stock units under the issuer's 2019 Employee Incentive Plan (the "Plan"), that vested on June 21, 2024. These sales are mandated by the Issuer's election under its Plan to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

F3 · price: The price reported in Column 4 is a weighted average price. These ADSs were sold in multiple transactions at prices ranging from $3.60 to $3.805, inclusive. The Reporting Person undertakes to provide to Mereo BioPharma Group plc ("Mereo"), any security holder of Mereo, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of ADSs sold at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4.

SEC source: 0000950170-24-077480 · ownership.xml · derivative · entry 2

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 60,000

Underlying: American Depository Shares · 90,000 shares

Expires 2025-01-25

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.underlying: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

SEC source: 0000950170-24-077480 · ownership.xml · nonDerivative · entry 1

Fox Christine Ann · CIK 0002005755 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 100,000

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · security: Each American Depositary Share ("ADS") represents five ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.

F2 · shares: Represents performance-based restricted stock unit ("PSU") earned under the issuer's 2019 Employee Incentive Plan (the "Plan") that vested on June 21, 2024 based on satisfaction of ADS price threshold values over a two year performance period (expiring on January 1, 2025).