Employee Benefit Plan, Description of Plan	12 Months Ended
Dec. 31, 2025
EBP 001
EBP, Description of Plan [Line Items]
EBP, Description of Plan	Description of the Plan The following is a description of the Retirement and Savings Plan for Amgen Manufacturing Limited LLC (the Plan). The description below provides only general information, and accordingly, participants should refer to the Plan document for a more complete description of the Plan’s provisions. General The Plan was established effective January 1, 2002, was amended and restated effective January 1, 2017, and was subsequently amended with the most recent amendment effective on or prior to December 31, 2025 adopted on June 7, 2024. The Plan was subsequently amended and restated effective January 1, 2026. The Plan is a defined contribution plan covering substantially all Puerto Rico resident employees of Amgen Manufacturing Limited LLC (the Company), a wholly owned subsidiary of Amgen Inc. (Amgen). The Plan is intended to qualify under Section 1081.01 of the Puerto Rico Internal Revenue Code of 2011, as amended (the PR Code) (see Note 4, Income Tax Status) and section 407(d)(3)(A) of the Employee Retirement Income Security Act of 1974 (ERISA). Contributions Subject to certain limitations (as defined in the Plan), participants may elect to contribute up to 30% of their eligible compensation in pre-tax contributions and after-tax contributions or a combination of these types of contributions (together, Individual Contributions). A participant’s pre-tax contributions are subject to the PR Code and Plan limitations and could not exceed $15,000 in 2025. Participants may elect to contribute after-tax contributions beginning January 1 of the year following the year the participant was hired. Participant after-tax contributions are subject to the PR Code and Plan limitations and could not exceed $1,500 in 2025. Unless an employee has voluntarily enrolled in the Plan or has declined to participate in the Plan within the first 30 days of employment, all newly eligible participants are automatically enrolled in the Plan, and contributions equal to 5% of their eligible compensation are withheld and contributed to the Plan as pre-tax contributions; such contributions are automatically increased by 1% per year until their contributions reach 10% of their eligible compensation. Participants may elect to adjust, cease or resume their Individual Contributions at any time. Participants who are at least age 50 by the close of the Plan year may also elect to make certain additional pre-tax Individual Contributions, referred to as catch-up contributions, that are subject to the PR Code and Plan limitations and could not exceed $1,500 in 2025. Participants may also contribute pre-tax and after-tax amounts representing distributions from certain other retirement plans qualified in Puerto Rico, referred to as rollover contributions (as defined in the Plan). Each pay period, the Company makes a non-elective contribution for all eligible participants, whether or not they have elected to make Individual Contributions to the Plan, equal to 4% of each participant’s eligible compensation up to a maximum of $14,000 in 2025 (Core Contributions). In addition, the Company makes a contribution equal to amounts contributed by the participant as pre-tax contributions, including catch-up contributions, of up to 5% of eligible compensation (Matching Contributions). Matching Contributions could not exceed $15,000 in 2025 (or $16,500 for catch-up eligible participants). Participants select the investments in which their Individual Contributions, including their Core Contributions and Matching Contributions (collectively, Company Contributions), are to be invested, electing among various alternatives, including Amgen common stock (Amgen stock). Participants may direct a maximum of 20% of contributions to be invested in Amgen stock. In addition, participants may transfer amounts among the investment options at any time, subject to certain limitations. Notwithstanding the foregoing, if 20% or more of the value of a participant’s Plan account is invested in Amgen stock, the Plan document provides that no transfers from other investment options can be made to invest in Amgen stock. The accounts of participants who have not made an investment election are allocated to investments under a qualified default investment alternative, which is intended to be compliant with ERISA regulations. At any time, participants may elect to alter the investments in their accounts made under a qualified default investment alternative. Vesting and Forfeitures Participants are immediately vested with respect to their Individual Contributions and Matching Contributions and earnings and losses (hereafter referred to as earnings) thereon. Participants hired prior to January 1, 2020, are also immediately vested with respect to their Core Contributions and earnings thereon. Participants hired on or after January 1, 2020, vest in full with respect to their Core Contributions and earnings thereon after three years of service, as defined by the terms of the Plan, or upon reaching age 65 while employed by the Company, if earlier. If a participant ceases to be an employee before fully vesting in their account, the non-vested Core Contributions and earnings thereon of the participant’s account will be treated as a forfeiture, as defined by the terms of the Plan, on the earlier of (a) the date the participant incurs a five-year break in service, as defined by the terms of the Plan or, (b) the date the participant receives a distribution of the entire vested portion of their account. Forfeitures are applied, in accordance with Plan provisions, to reduce Core or Matching Contributions, to reinstate forfeitures of reemployed participants, to reinstate the accounts of lost participants or beneficiaries (as defined in the Plan), to reduce Plan administrative expenses for the current or immediately following Plan year, and/or for any other purpose permitted under federal regulations or other applicable authority. Participant Accounts Each participant’s account is credited with: (a) the participant’s Individual Contributions; (b) an allocation of Company Contributions; and (c) earnings. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s account. Plan Investments Plan participants can invest in seven different asset classes as well as Amgen stock or can actively manage their account under a self-directed brokerage arrangement in which a wider array of investment options are available. The value of an investment in an asset class is determined by its underlying investment vehicles, which may include one or more of the following: mutual funds, collective trust funds and portfolios, which are separately managed exclusively for the benefit of Plan participants and their beneficiaries (separately managed portfolios). The separately managed portfolios are composed primarily of investments in publicly traded common and preferred stocks. The asset classes are designed to provide participants with choices among a variety of investment objectives. Payments of Benefits Subject to Plan limitations, upon termination of employment, including termination due to disability (as defined in the Plan) or retirement, a participant may elect to receive a full or partial distribution of his or her account balance in: (a) a single payment in cash; (b) a single distribution in full shares of Amgen stock (with any fractional shares paid in cash); (c) a single distribution paid in a combination of cash and full shares of Amgen stock; or (d) a rollover distribution to an eligible retirement plan. Participants may also elect to maintain their account balance in the Plan subsequent to termination of employment, provided that their account balance is greater than $1,000. If a participant dies before receiving the value of his or her account balance, the participant’s beneficiary may elect to receive the distribution of remaining funds from among the alternatives described above, subject to certain Plan limitations. No withdrawals may be made from the Plan while a participant continues to be employed by the Company except in certain circumstances including, but not limited to, financial hardship, disability and attainment of age 59 1/2. Notes Receivable from Participants Subject to certain restrictions, a participant can have up to two loans outstanding at any one time from his or her Plan account with a combined maximum loan amount that may not exceed the lesser of: (a) 50% of the participant’s account balance or (b) $50,000 less certain adjustments, as applicable (as defined in the Plan). A participant’s loan is secured by his or her Plan account balance. Loans bear interest at fixed rates which, until changed by the Company, are based on the prime rate plus one percentage point as published in The Wall Street Journal, determined as of the last day of the calendar quarter preceding origination or such other rate as may be required by law. Loans are generally payable in installments over periods ranging from one to five years, unless the loan is used to acquire a principal residence for which the term of the loan may be up to 20 years. Principal and interest payments are allocated to the participant’s account. Plan Termination Although it has not expressed any intent to do so, the Company has the right under the Plan to terminate the Plan subject to the provisions of ERISA. Upon termination, participants would become fully vested in Core Contributions and receive distributions of their account balances. Trustee and Custodians Banco Popular de Puerto Rico is the Plan’s trustee. Bank of America, N.A. is the Plan’s custodian with respect to the self-directed brokerage arrangement and the Amgen common stock fund. The Northern Trust Company, NA (Northern) is the Plan’s custodian with respect to the asset classes.

The following is a description of the Retirement and Savings Plan for Amgen Manufacturing Limited LLC (the Plan). The description below provides only general information, and accordingly, participants should refer to the Plan document for a more complete description of the Plan’s provisions.

The Plan was established effective January 1, 2002, was amended and restated effective January 1, 2017, and was subsequently amended with the most recent amendment effective on or prior to December 31, 2025 adopted on June 7, 2024. The Plan was subsequently amended and restated effective January 1, 2026. The Plan is a defined contribution plan covering substantially all Puerto Rico resident employees of Amgen Manufacturing Limited LLC (the Company), a wholly owned subsidiary of Amgen Inc. (Amgen). The Plan is intended to qualify under Section 1081.01 of the Puerto Rico Internal Revenue Code of 2011, as amended (the PR Code) (see Note 4, Income Tax Status) and section 407(d)(3)(A) of the Employee Retirement Income Security Act of 1974 (ERISA).

Subject to certain limitations (as defined in the Plan), participants may elect to contribute up to 30% of their eligible compensation in pre-tax contributions and after-tax contributions or a combination of these types of contributions (together, Individual Contributions). A participant’s pre-tax contributions are subject to the PR Code and Plan limitations and could not exceed $15,000 in 2025. Participants may elect to contribute after-tax contributions beginning January 1 of the year following the year the participant was hired. Participant after-tax contributions are subject to the PR Code and Plan limitations and could not exceed $1,500 in 2025. Unless an employee has voluntarily enrolled in the Plan or has declined to participate in the Plan within the first 30 days of employment, all newly eligible participants are automatically enrolled in the Plan, and contributions equal to 5% of their eligible compensation are withheld and contributed to the Plan as pre-tax contributions; such contributions are automatically increased by 1% per year until their contributions reach 10% of their eligible compensation. Participants may elect to adjust, cease or resume their Individual Contributions at any time.

Participants who are at least age 50 by the close of the Plan year may also elect to make certain additional pre-tax Individual Contributions, referred to as catch-up contributions, that are subject to the PR Code and Plan limitations and could not exceed $1,500 in 2025. Participants may also contribute pre-tax and after-tax amounts representing distributions from certain other retirement plans qualified in Puerto Rico, referred to as rollover contributions (as defined in the Plan).

Each pay period, the Company makes a non-elective contribution for all eligible participants, whether or not they have elected to make Individual Contributions to the Plan, equal to 4% of each participant’s eligible compensation up to a maximum of $14,000 in 2025 (Core Contributions). In addition, the Company makes a contribution equal to amounts contributed by the participant as pre-tax contributions, including catch-up contributions, of up to 5% of eligible compensation (Matching Contributions). Matching Contributions could not exceed $15,000 in 2025 (or $16,500 for catch-up eligible participants).

Participants select the investments in which their Individual Contributions, including their Core Contributions and Matching Contributions (collectively, Company Contributions), are to be invested, electing among various alternatives, including Amgen common stock (Amgen stock). Participants may direct a maximum of 20% of contributions to be invested in Amgen stock. In addition, participants may transfer amounts among the investment options at any time, subject to certain limitations. Notwithstanding the foregoing, if 20% or more of the value of a participant’s Plan account is invested in Amgen stock, the Plan document provides that no transfers from other investment options can be made to invest in Amgen stock.

The accounts of participants who have not made an investment election are allocated to investments under a qualified default investment alternative, which is intended to be compliant with ERISA regulations. At any time, participants may elect to alter the investments in their accounts made under a qualified default investment alternative.

Participants are immediately vested with respect to their Individual Contributions and Matching Contributions and earnings and losses (hereafter referred to as earnings) thereon. Participants hired prior to January 1, 2020, are also immediately vested with respect to their Core Contributions and earnings thereon. Participants hired on or after January 1, 2020, vest in full with respect to their Core Contributions and earnings thereon after three years of service, as defined by the terms of the Plan, or upon

reaching age 65 while employed by the Company, if earlier. If a participant ceases to be an employee before fully vesting in their account, the non-vested Core Contributions and earnings thereon of the participant’s account will be treated as a forfeiture, as defined by the terms of the Plan, on the earlier of (a) the date the participant incurs a five-year break in service, as defined by the terms of the Plan or, (b) the date the participant receives a distribution of the entire vested portion of their account. Forfeitures are applied, in accordance with Plan provisions, to reduce Core or Matching Contributions, to reinstate forfeitures of reemployed participants, to reinstate the accounts of lost participants or beneficiaries (as defined in the Plan), to reduce Plan administrative expenses for the current or immediately following Plan year, and/or for any other purpose permitted under federal regulations or other applicable authority.

Each participant’s account is credited with: (a) the participant’s Individual Contributions; (b) an allocation of Company Contributions; and (c) earnings. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s account.

Plan participants can invest in seven different asset classes as well as Amgen stock or can actively manage their account under a self-directed brokerage arrangement in which a wider array of investment options are available. The value of an investment in an asset class is determined by its underlying investment vehicles, which may include one or more of the following: mutual funds, collective trust funds and portfolios, which are separately managed exclusively for the benefit of Plan participants and their beneficiaries (separately managed portfolios). The separately managed portfolios are composed primarily of investments in publicly traded common and preferred stocks. The asset classes are designed to provide participants with choices among a variety of investment objectives.

Subject to Plan limitations, upon termination of employment, including termination due to disability (as defined in the Plan) or retirement, a participant may elect to receive a full or partial distribution of his or her account balance in: (a) a single payment in cash; (b) a single distribution in full shares of Amgen stock (with any fractional shares paid in cash); (c) a single distribution paid in a combination of cash and full shares of Amgen stock; or (d) a rollover distribution to an eligible retirement plan.

If a participant dies before receiving the value of his or her account balance, the participant’s beneficiary may elect to receive the distribution of remaining funds from among the alternatives described above, subject to certain Plan limitations.

Subject to certain restrictions, a participant can have up to two loans outstanding at any one time from his or her Plan account with a combined maximum loan amount that may not exceed the lesser of: (a) 50% of the participant’s account balance or (b) $50,000 less certain adjustments, as applicable (as defined in the Plan). A participant’s loan is secured by his or her Plan account balance. Loans bear interest at fixed rates which, until changed by the Company, are based on the prime rate plus one percentage point as published in The Wall Street Journal, determined as of the last day of the calendar quarter preceding origination or such other rate as may be required by law. Loans are generally payable in installments over periods ranging from one to five years, unless the loan is used to acquire a principal residence for which the term of the loan may be up to 20 years. Principal and interest payments are allocated to the participant’s account.

Although it has not expressed any intent to do so, the Company has the right under the Plan to terminate the Plan subject to the provisions of ERISA. Upon termination, participants would become fully vested in Core Contributions and receive distributions of their account balances.

Banco Popular de Puerto Rico is the Plan’s trustee. Bank of America, N.A. is the Plan’s custodian with respect to the self-directed brokerage arrangement and the Amgen common stock fund. The Northern Trust Company, NA (Northern) is the Plan’s custodian with respect to the asset classes.