SOUTHERN CALIFORNIA EDISON Co

Nature of Estimates Required. As part of the process of preparing its consolidated financial statements, Edison International and SCE are required to estimate income taxes for each jurisdiction in which they operate. This process involves estimating actual current period tax expense together with assessing temporary differences resulting from differing treatment of items, such as depreciation, for tax and accounting purposes. These differences result in deferred tax assets and liabilities, which are included within Edison International's and SCE's consolidated balance sheets, including net operating loss and tax credit carryforwards. Certain estimates and assumptions are required to determine whether deferred tax assets can and will be utilized in future periods. Based on currently enacted tax laws, Edison International expects to generate sufficient taxable income to fully utilize all loss and credit carryovers set to expire beyond 2023.

Edison International and SCE take certain tax positions they believe are in accordance with the applicable tax laws. However, these tax positions are subject to interpretation by the Internal Revenue Service, state tax authorities and the courts. Edison International and SCE determine uncertain tax positions in accordance with the authoritative guidance.

Key Assumptions and Approach Used. In determining whether it is more likely than not that all or some portion of net operating loss and tax credit carryforwards can be utilized, management analyzes the trend of GAAP earnings and then estimates the impact of future taxable income, reversing temporary differences and available prudent and feasible tax planning strategies based on currently enacted tax laws.

Accounting for tax obligations requires management judgment. Edison International's and SCE's management use judgment in determining whether the evidence indicates it is more likely than not, based solely on the technical merits, that a tax position will be sustained, and to determine the amount of tax benefits to be recognized. Judgment is also used in determining the likelihood a tax position will be settled and possible settlement outcomes. In assessing uncertain tax positions Edison International and SCE consider, among others, the following factors: the facts and circumstances of the position, regulations, rulings, and case law, opinions or views of legal counsel and other advisers, and the experience gained from similar tax positions. Edison International and SCE evaluate uncertain tax positions at the end of each reporting period and make adjustments when warranted based on changes in fact or law.

*Effect if Different Assumptions Used.*Should a change in facts or circumstances, including a change in enacted tax legislation, lead to a change in judgment about the ultimate realizability of a deferred tax asset, Edison International and

SCE would record or adjust the related valuation allowance in the period that the change in facts and circumstances occurs, along with a corresponding increase or decrease in the provision for income taxes.

Actual income taxes may differ from the estimated amounts which could have a significant impact on the liabilities, revenue and expenses recorded in the financial statements. Edison International and SCE continue to be under audit or subject to audit for multiple years in various jurisdictions. Significant judgment is required to determine the tax treatment of particular tax positions that involve interpretations of complex tax laws. Such liabilities are based on judgment and a final determination could take many years from the time the liability is recorded. Furthermore, settlement of tax positions included in open tax years may be resolved by compromises of tax positions based on current factors and business considerations that may result in material adjustments to income taxes previously estimated. For a discussion of current and deferred taxes, net operating losses and tax credit carryforwards, accounting for uncertainty in income taxes, unrecognized tax benefits, and tax disputes, see "Notes to Consolidated Financial Statements—Note 8. Income Taxes."