General — The following description of the Johns Manville Employees 401(k) Plan (the “Plan”) provides only general information. Participants should refer to the Plan document for a more complete description of the Plan’s provisions.

The Plan is a defined contribution plan sponsored by Johns Manville Corporation (the “Plan Sponsor”) and offered through its wholly owned subsidiary, Johns Manville (the “Company”). The Plan provides eligible employees a convenient means for regular and systematic savings through pre-tax contributions, after-tax contributions and Roth accounts. The Plan offers multiple investment options through Fidelity Management Trust Company (“Fidelity” or the “Trustee”), the trustee of the Plan, which administers, manages, and reports the Plan’s investment transactions. The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974 (ERISA).

Investments — Participants direct the investment of their contributions into the various funds offered by the Plan. The Plan offers mutual funds, target date common collective trust funds and a unitized stock fund that includes Class B common stock of Berkshire Hathaway, Inc. (“Berkshire Common Stock”), the ultimate parent company of Johns Manville Corporation.

Eligibility — All regular employees including full-time, part-time, interns, non-union hourly and union hourly employees at participating Company locations are eligible to become Plan participants on the first day of employment or immediately upon reemployment.

The Plan includes an auto-enrollment provision whereby all newly eligible employees are automatically enrolled in the Plan 31 days following their dates of hire, unless they affirmatively elect not to participate in the Plan or make their own election. Automatically enrolled participants have their pre-tax deferral rate set at 3% of eligible compensation and their contributions are invested in the T. Rowe Price Retirement Date Trust that aligns with their projected year of retirement until changed by the participant.

Company Contributions — The Company contribution for salaried employees and non-union hourly employees is based on a 50% fixed match on the first 6% of pre-tax and/or Roth employee contributions up to a maximum of 3% of eligible compensation, plus up to 50% variable match on the first 6% of pre-tax and/or Roth employee contributions up to a maximum of 3% of eligible compensation based on the operating performance of the Company and management’s sole discretion. The Company may also, at its sole discretion, contribute an additional variable match of up to 1% of eligible compensation if the participant is contributing between 6% and 7% in pre-tax and/or Roth contributions.

The Company contributions for union hourly employees is based on 50% of the first 6% of pre-tax and/or Roth contributions up to a maximum of 3% of eligible compensation. The Company may make variable matching contributions in a specified percentage (as agreed upon in each collective bargaining agreement) up to 50% of the first 6% of pre-tax and/or Roth employee contributions up to a maximum of 3% of eligible compensation. Such variable matching contributions are based upon the operating performance of the Company and management’s sole discretion. All employer contributions are based on negotiated rates within the collective bargaining agreements.

Company contributions of $12,525,010 and $14,704,344 related to the Company’s variable match were accrued for as of December 31, 2025 and 2024, respectively. Voluntary after-tax contributions, catch-up contributions and rollover contributions are not matched by the Company. The Company’s annual contribution made on behalf of any one employee is subject to certain maximums as specified in the Plan and the Internal Revenue Code (IRC).

Participant Contributions — Eligible employees may contribute to the Plan through a reduction in salary on a pretax and/or Roth basis from 1% to 75% of eligible compensation. Employees may elect to contribute 1% to 9% of eligible compensation on an after-tax basis regardless of the percentage of pretax and Roth contributions. Participants may also contribute amounts representing distributions from other qualified defined benefit or defined contribution plans, which represent a rollover to the Plan. Contributions are subject to certain IRC limitations. In addition to the regular catch-up contributions for participants aged 50 and older, beginning in 2025, the Internal Revenue Service (IRS) introduced an increased catch-up contribution limit for employees that are or will be the ages of 60 to 63 within the 2025 calendar year.

Contribution Limitations — Amounts invested by a participant in the Berkshire Hathaway Class B Unitized Stock Fund (Berkshire Fund), an investment option of the Plan that invests in Berkshire Common Stock, cannot exceed 25% of their contributions or total value of their account.

Participant Accounts — Individual accounts are maintained for each Plan participant. Each participant’s account is credited with the participant’s contribution, the Company’s matching contribution, and allocations of the Company’s discretionary contributions, participant forfeitures, as applicable, and Plan earnings, and charged with withdrawals and an allocation of Plan losses and administrative expenses. Allocations are based on participant earnings or account balances, as defined. The benefit to which a participant is entitled is

ASC 820, Fair Value Measurement, provides a framework for measuring fair value, and requires additional disclosures about fair value measurements. In accordance with ASC 820, the Plan classifies its investments into Level 1, which refers to securities valued using quoted prices from active markets for identical assets; Level 2, which refers to securities not traded on an active market but for which observable market inputs are readily available; and Level 3, which refers to securities valued based on significant unobservable inputs. Investments are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.

Asset Valuation Techniques - Maximize the use of relevant observable inputs and minimize the use of unobservable inputs. The following is a description of the valuation methodologies used for assets measured at fair value.

Berkshire Fund - A separately managed account that is a unitized stock fund that operates similarly to a mutual fund, in that it is composed of stock, and a money market mutual fund. The inclusion of this money market mutual fund provides liquid assets to allow for the daily processing of transfers, loans, and withdrawals. The value of a unit in a unitized stock fund is based on the Net Asset Value (NAV), which is the value of the underlying common stock and the money market mutual fund held by the stock fund. The market value of the stock portion of the Berkshire Fund is based on the closing market price of the Berkshire Common Stock on the New York Stock Exchange multiplied by the number of shares held in the fund. The individual assets of a stock fund are considered separately as individual investments for accounting, auditing, and financial statement reporting purposes.

Mutual funds – Valued at the daily closing price as reported by the fund. Mutual funds held by the Plan are open-ended mutual funds that are registered with the Securities and Exchange Commission. These funds are required to publish their daily NAV and to transact at that price. The mutual funds held by the Plan are deemed to be actively traded.

Collective trust funds – Valued at the NAV of units of a collective trust. The NAV as provided by the trustee is used as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund less its liabilities. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Participant transactions (purchases and sales) may occur daily. Were the Plan to initiate a full redemption of the collective trust, the investment advisor reserves the right to temporarily delay withdrawal from the Plan in order to ensure that securities liquidation will be carried out in an orderly business manner.

The IRS has determined and informed the Company by a letter dated January 26, 2018, that the Plan and related trust was designed in accordance with the applicable regulations of the IRC requirements. The Plan has been amended since receiving the letter. The Plan Sponsor believes the Plan has maintained its tax-exempt status, therefore, no provision for income taxes has been included in the Plan’s financial statements.

GAAP requires Plan management to evaluate tax provisions taken by the Plan and recognize a tax liability (or asset) if the Plan has taken an uncertain position that more likely than not would not be sustained upon examination by the IRS. Plan management has analyzed the tax positions taken by the Plan, and has concluded that as of December 31, 2025 and 2024, there are no uncertain positions taken or expected to be taken that would require recognition of a liability (or asset) or disclosure in the financial statements. The Plan is subject to routine audits by taxing jurisdictions; however, there are currently no audits for any tax periods in progress. The Plan administrator believes it is no longer subject to income tax examinations for years prior to 2022.

Although it has not expressed any intention to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions set forth in ERISA. In the event that the Plan is terminated by the Company, participant accounts would become fully vested. The assets of the Plan would be distributed to the participants based on their account balances. In addition, any previously forfeited amounts that had not been applied to reduce Company contributions would be credited ratably to the accounts of the participants remaining in the Plan at the time of such termination.

Certain Plan investments as of December 31, 2025 and 2024 are shares of a collective trust and mutual funds managed by Fidelity Management and Research Company. Fidelity Investments Institutional Operations Company, an affiliate of Fidelity Management Trust Company, the custodian of the Plan, is the recordkeeper as defined by the Plan and, therefore, these transactions qualify as exempt party-in-interest transactions. Fidelity Investments Institutional Operations Company and Fidelity Management Trust Company are underlying business units of Fidelity Management and Research Company, therefore, these transactions qualify as exempt party-in-interest transactions. Fees paid by the Plan for investment management services were included as a reduction of the return earned on each fund within the Plan. The Plan also issues loans to participants, which are secured by the vested balances in the participants’ accounts.

As of December 31, 2025 and 2024 the Berkshire Fund held 109,496 shares of the common stock with a cost basis of $18,137,384 and 114,031 shares of common stock with a cost basis of $17,843,183, respectively. During 2025 the Plan purchased 3,020 shares of common stock with a value of $1,525,789 and sold 7,555 shares with a value of $3,745,659. These transactions in the Berkshire Common Stock qualify as exempt party-in-interest transactions.

In 2024, the Company remitted certain participant contributions and loan payments of $1,657,130 to the Trustee later than required by DOL Regulation 2510.3-102. The Company paid the required excise tax on the transactions for Plan year 2024 on June 19, 2025. In addition, on June 6, 2025, participant accounts were credited with the amount of investment income that would have been earned had the participant contributions been remitted on a timely basis.

JOHNS MANVILLE EMPLOYEES 401(k) PLAN

EIN 84-0856796

Plan Number: 005

FORM 5500, SCHEDULE H, PART IV, LINE 4i — SCHEDULE OF ASSETS (HELD AT END OF YEAR)

AS OF DECEMBER 31, 2025

* Exempt party-in-interest (Note 6).

** Cost information is not required for participant-directed investments and, therefore, is not included.

JOHNS MANVILLE EMPLOYEES 401(k) PLAN

EIN 84-0856796

Plan Number: 005