This document contains regulations under section 1502 of the Internal Revenue Code (Code). The regulations update the regulations under section 1502 by revising and removing text that has become outdated as a result of changes in the law. The regulations affect corporations filing consolidated returns. The proposed regulations withdrew or partially withdrew numerous notices of proposed rulemaking. The IRS accepted public comments from August 7,2023, to November 6,2023. The IRS reopened the comment period on December 6, 2023, and accepted public comments until February 5, 2024. Final regulations were published on December 30, 2024. In conjunction with the final regulations, the Treasury Department and the IRS published additional proposed regulations that would clarify the timing of a single basis adjustment required by statute.