MPLX LP

3. Accounting Standards and Disclosure Rules

Recently Adopted

ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures

The FASB issued this ASU to update reportable segment disclosure requirements primarily by requiring enhanced disclosures about significant segment expenses. During the fourth quarter of 2024, we applied the amendments in this ASU retrospectively to all periods presented in the financial statements. The enhanced disclosures for significant segment expenses are presented in Note 10 - Segment Information.

ASU 2023-01, Leases (Topic 842): Common Control Arrangements

The FASB issued this ASU to amend certain provisions of ASC 842 that apply to arrangements between related parties under common control. The ASU amends the accounting for the amortization period of leasehold improvements in common-control leases for all entities and requires certain disclosures when the lease term is shorter than the useful life of the asset. During the first quarter of 2024, we adopted this ASU and it did not have a material impact on our financial statements or disclosures.

Not Yet Adopted

ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses

In November 2024, the FASB issued an ASU to require more detailed information about specified categories of expenses (purchases of inventory, employee compensation, depreciation, amortization, and depletion) included in certain expense captions presented on the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the financial statements. We are currently evaluating the impact this ASU will have on our disclosures.

SEC Release No. 33-11275, The Enhancement and Standardization of Climate-Related Disclosures for Investors

In March 2024, the SEC adopted rules under SEC Release No. 33-11275, The Enhancement and Standardization of Climate-Related Disclosures for Investors, which requires registrants to provide certain climate-related information in their annual reports. As part of the disclosures, material impacts from severe weather events and other natural conditions will be required in the audited financial statements. In April 2024, the SEC voluntarily stayed the rules pending judicial review. Pending the results of the judicial review, the disclosure requirements are effective for the Partnership’s Annual Report on Form 10-K for the fiscal year ending December 31, 2025. We are evaluating the impact these rules, if effective, will have on our disclosures and monitoring the status of the judicial review.