OGE ENERGY CORP.

COMBINED NOTES TO THE CONDENSED FINANCIAL STATEMENTS

Index of Combined Notes to Condensed Financial Statements

The Combined Notes to the Condensed Financial Statements are a combined presentation for OGE Energy and OG&E. The following table indicates the Registrant(s) to which each Note applies.

1. Summary of Significant Accounting Policies

Organization

OGE Energy is a holding company whose primary investment provides electricity in Oklahoma and western Arkansas. OGE Energy's electric company operations are conducted through its wholly-owned subsidiary, OG&E, which generates, transmits, distributes and sells electric energy in Oklahoma and western Arkansas and are reported through OGE Energy's electric company business segment. OG&E's rates are subject to regulation by the OCC, the APSC and the FERC. OG&E was incorporated in 1902 under the laws of the Oklahoma Territory and is the largest electric company in Oklahoma, with a franchised service territory that includes Fort Smith, Arkansas and the surrounding communities. OG&E sold its retail natural gas business in 1928 and is no longer engaged in the natural gas distribution business.

The accounts of OGE Energy and its wholly-owned subsidiaries, including OG&E, are included in OGE Energy's condensed consolidated financial statements. All intercompany transactions and balances are eliminated in such consolidation.

Basis of Presentation

The condensed financial statements included herein have been prepared by the Registrants, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations; however, the Registrants believe that the disclosures are adequate to prevent the information presented from being misleading.

In the opinion of management, all adjustments necessary to fairly present the financial position of the Registrants at March 31, 2025 and December 31, 2024, the results of the Registrants' operations for the three months ended March 31, 2025 and 2024 and the Registrants' cash flows for the three months ended March 31, 2025 and 2024 have been included and are of a normal, recurring nature except as otherwise disclosed. Management also has evaluated the impact of events occurring after March 31, 2025 up to the date of issuance of these condensed financial statements, and these statements contain all necessary adjustments and disclosures resulting from that evaluation.

Due to seasonal fluctuations and other factors, the Registrants' operating results for the three months ended March 31, 2025 are not necessarily indicative of the results that may be expected for the year ending December 31, 2025 or for any future period. The condensed financial statements and notes thereto should be read in conjunction with the audited financial statements and notes thereto included in the Registrants'2024 Form 10-K.

Accounting Records

The accounting records of OG&E are maintained in accordance with the Uniform System of Accounts prescribed by the FERC and adopted by the OCC and the APSC. Additionally, OG&E, as a regulated electric company, is subject to accounting principles for certain types of rate-regulated activities, which provide that certain incurred costs that would otherwise be charged to expense can be deferred as regulatory assets, based on the expected recovery from customers in future rates. Likewise, certain actual or anticipated credits that would otherwise reduce expense can be deferred as regulatory liabilities, based on the expected flowback to customers in future rates. Management's expected recovery of deferred costs and flowback of deferred credits generally results from specific decisions by regulators granting such ratemaking treatment.

OG&E records certain incurred costs and obligations as regulatory assets or liabilities if, based on regulatory orders or other available evidence, it is probable that the costs or obligations will be included in amounts allowable for recovery or refund in future rates. The following table presents a summary of OG&E's regulatory assets and liabilities.

(A)

Included in Other Current Assets in the condensed balance sheets.

(B)

Included in Other Current Liabilities in the condensed balance sheets.

Management continuously monitors the future recoverability of regulatory assets. When in management's judgment future recovery becomes impaired, the amount of the regulatory asset is adjusted, as appropriate. If OG&E were required to discontinue the application of accounting principles for certain types of rate-regulated activities for some or all of its operations, it could result in writing off the related regulatory assets or liabilities, which could have significant financial effects.

Allowance for Uncollectible Accounts Receivable

Customer balances are generally written off if not collected within six months after the final billing date. The allowance for uncollectible accounts receivable for OG&E is generally calculated by multiplying the last six months of electric revenue by the provision rate, which is based on a historical average of actual balances written off and is adjusted for current conditions and supportable forecasts as necessary. To the extent the historical collection rates, when incorporating forecasted conditions, are not representative of future collections, there could be an effect on the amount of uncollectible expense recognized. Also, a portion of the uncollectible provision related to fuel within the Oklahoma jurisdiction is being recovered through the fuel adjustment clause. The allowance for uncollectible accounts receivable is a reduction to Accounts Receivable in the condensed balance sheets and is included in Other Operation and Maintenance Expense in the condensed statements of income.

New business customers are required to provide a security deposit in the form of cash, bond or irrevocable letter of credit that is refunded when the account is closed or when certain requirements are met. New residential customers whose outside credit scores indicate an elevated risk are required to provide a security deposit that is refunded based on customer protection rules defined by the OCC and the APSC. The payment behavior of all existing customers is continuously monitored, and, if the payment behavior indicates sufficient risk within the meaning of the applicable utility regulation, customers will be required to provide a security deposit.

Accumulated Other Comprehensive Income (Loss)

The following tables present changes in the components of accumulated other comprehensive income (loss) attributable to OGE Energy during thethree months ended March 31, 2025 and 2024. All amounts below are presented net of tax.

The following table presents significant amounts reclassified out of accumulated other comprehensive income (loss) attributable to OGE Energy by the respective line items in net income during thethree months ended March 31, 2025 and 2024.

(A)

These accumulated other comprehensive income (loss) components are included in the computation of net periodic benefit cost (see Note 10 for additional information).

2. Accounting Pronouncements

In December 2023, the Financial Accounting Standards Board issued ASU 2023-09, "Income Taxes (Topic 740) Improvements to Income Tax Disclosures." The amendments in this update require public entities on an annual basis to (i) disclose specific categories in the rate reconciliation and (ii) provide additional information for reconciling items that meet a quantitative threshold. Further, the amendments require entities to disclose on an annual basis income taxes paid (net of refunds received) disaggregated by federal (national), state and foreign taxes and to disaggregate the information by jurisdiction based on a quantitative threshold. The Registrants adopted this standard effective January 1, 2025 and do not expect it to have a material impact on their annual financial statement disclosures.

In November 2024, the Financial Accounting Standards Board issued ASU 2024-03, "Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures." The amendments in this update improve financial reporting by requiring disclosure of additional information about specific expense categories in the notes to financial statements on an annual and interim basis. This standard is effective for fiscal years beginning after December 15, 2026 and interim periods beginning after December 15, 2027. Early adoption is permitted. The Registrants are evaluating the impact of this standard and do not believe it will have a material impact on their financial statement disclosures.

The Registrants believe that other recently adopted and recently issued accounting standards that are not yet effective do not appear to have a material impact on the Registrants' financial position, results of operations or cash flows upon adoption.

3. Revenue Recognition

The following table presents OG&E's revenues from contracts with customers disaggregated by customer classification. OG&E's operating revenues disaggregated by customer classification can be found in "OG&E (Electric Company) Results of Operations" within "Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations."

4. Fair Value Measurements

The classification of the Registrants' fair value measurements requires judgment regarding the degree to which market data is observable or corroborated by observable market data. GAAP establishes a fair value hierarchy that prioritizes the inputs used to measure fair value based on observable and unobservable data. The hierarchy categorizes the inputs into three levels, with the highest priority given to quoted prices in active markets for identical unrestricted assets or liabilities (Level 1) and the lowest priority given to unobservable inputs (Level 3). Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The three levels defined in the fair value hierarchy are as follows:

Level 1 inputs are quoted prices in active markets for identical unrestricted assets or liabilities that are accessible at the measurement date.

Level 2 inputs are inputs other than quoted prices in active markets included within Level 1 that are either directly or indirectly observable at the reporting date for the asset or liability for substantially the full term of the asset or liability. Level 2 inputs include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active.

Level 3 inputs are prices or valuation techniques for the asset or liability that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). Unobservable inputs reflect the reporting entity's own assumptions about the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk).

The Registrants hadno financial instruments measured at fair value on a recurring basis at March 31, 2025 and December 31, 2024. The following table presents the carrying amount and fair value of the Registrants' financial instruments at March 31, 2025 and December 31, 2024, as well as the classification level within the fair value hierarchy.

5. Stock-Based Compensation

The following table presents the Registrants' pre-tax compensation expense and related income tax benefit for thethree months ended March 31, 2025 and 2024 related to performance units and restricted stock units for the Registrants' employees.

During the three months ended March 31, 2025, OGE Energy issued 234,476 shares of new common stock pursuant to OGE Energy's Stock Incentive Plan to satisfy payouts of earned performance units and restricted stock unit grants to the Registrants' employees.

During the three months ended March 31, 2025, OGE Energy granted 216,426 performance units (based on total shareholder return over a three-year period) and 116,532 restricted stock units (three-year cliff vesting period) to the Registrants' employees at $55.43 and $43.67 fair value per share, respectively.

6. Income Taxes

OGE Energy files consolidated income tax returns in the U.S. federal jurisdiction and various state jurisdictions. OG&E is a part of the consolidated income tax return of OGE Energy. With few exceptions, the Registrants are no longer subject to U.S. federal tax or state and local examinations by tax authorities for years prior to 2021. Income taxes are generally allocated to each company in the affiliated group, including OG&E, based on its stand-alone taxable income or loss. Federal investment tax credits previously claimed on electric utility property have been deferred and will be amortized to income over the life of the related property. Oklahoma investment tax credits are also earned on investments at electric generating facilities which further reduce OG&E's effective tax rate.

7. Common Equity

Automatic Dividend Reinvestment and Stock Purchase Plan

OGE Energy issued 73,307 new shares of common stock under its Automatic Dividend Reinvestment and Stock Purchase Plan during thethree months ended March 31, 2025 and received proceeds of $3.1 million. OGE Energy may, from time to time, issue additional shares under its Automatic Dividend Reinvestment and Stock Purchase Plan to fund capital requirements or working capital needs. As of March 31, 2025, there were 4,249,268 shares of unissued common stock reserved for issuance under OGE Energy's Automatic Dividend Reinvestment and Stock Purchase Plan.

Earnings Per Share

Basic earnings per share is calculated by dividing net income attributable to OGE Energy by the weighted-average number of OGE Energy's common shares outstanding during the period. In the calculation of diluted earnings per share, weighted-average shares outstanding are increased for additional shares that would be outstanding if potentially dilutive securities were converted to common stock. Potentially dilutive securities for OGE Energy consist of performance units and restricted stock units. The following table presents the calculation of basic and diluted earnings per share for OGE Energy.

8. Long-Term Debt

At March 31, 2025, the Registrants were in compliance with all of their debt agreements.

OG&E Industrial Authority Bonds

OG&E has tax-exempt pollution control bonds with optional redemption provisions that allow the holders to request repayment of the bonds on any business day. The following table presents information about these bonds, which can be tendered at the option of the holder during the next 12 months.

OG&E repaid $32.4 million of Muskogee Industrial Authority bonds that matured on January 1, 2025.

All of these bonds are subject to an optional tender at the request of the holders, at 100 percent of the principal amount, together with accrued and unpaid interest to the date of purchase. The bond holders, on any business day, can request repayment of the bond by delivering an irrevocable notice to the tender agent stating the principal amount of the bond, payment instructions for the purchase price and the business day the bond is to be purchased. The repayment option may only be exercised by the holder of a bond for the principal amount. When a tender notice has been received by the trustee, a third-party remarketing agent for the bonds will attempt to remarket any bonds tendered for purchase. This process occurs once per week. Since the original issuance of these series of bonds in 1995 and 1997, the remarketing agent has successfully remarketed all tendered bonds. If the remarketing agent is unable to remarket any such bonds, OG&E is obligated to repurchase such unremarketed bonds. As OG&E has both the intent and ability to refinance the bonds on a long-term basis and such ability is supported by an ability to consummate the refinancing, the remarketing of bonds does not result in short-term debt classification in the condensed balance sheets. OG&E believes that it has sufficient liquidity to meet these obligations.

Issuance of Long-Term Debt

On April 1, 2025, OG&E issued $350.0 million of 5.80 percent senior notes due April 1, 2055. The proceeds from this issuance were added to OG&E's general funds to be used for the repayment of short-term debt and borrowings under its revolving credit facility, and to fund OG&E's capital investment program and working capital needs.

9. Credit Facilities and Short-Term Debt

The Registrants borrow, as necessary, by the issuance of commercial paper and by borrowings under their revolving credit agreements. The following table presents information regarding the Registrants' revolving credit agreements at March 31, 2025.

(A)

Includes direct borrowings under the revolving credit agreements, commercial paper borrowings and letters of credit at March 31, 2025. Typically, OGE Energy issues commercial paper to address consolidated operational activity, and OG&E will borrow from OGE Energy under the intercompany borrowing agreement as discussed below in footnote (E).

(B)

This bank facility is available to back up OGE Energy's commercial paper borrowings and to provide revolving credit borrowings. This bank facility can also be used as a letter of credit facility.

(C)

OGE Energy has a $120.0 million floating rate unsecured three-year credit agreement, of which $60.0 million is considered a revolving loan, which is included in the table above, and $60.0 million is considered a term loan. The credit agreement, under certain circumstances, may be increased to a maximum commitment limit of $155.0 million and includes a maximum leverage ratio of 0.70 to 1.0. The other covenants under this credit agreement are substantially the same as OGE Energy's existing $550.0 million revolving credit agreement.

(D)

This bank facility is available to back up OG&E's commercial paper borrowings and to provide revolving credit borrowings. This bank facility can also be used as a letter of credit facility. At March 31, 2025, there was $100.0 million in outstanding borrowings at a weighted-average interest rate of 5.42 percent under the revolving credit facility, which was classified as Long-Term Debt in the Registrants' condensed balance sheet.

(E)

OG&E has an intercompany borrowing agreement with OGE Energy whereby OG&E has access to up to $450.0 million of OGE Energy's revolving credit amount. This agreement has a termination date of December 18, 2029. At March 31, 2025, there was $418.4 million in advances to parent, of which $356.7 million is under the intercompany borrowing agreement.

(F)

Represents the weighted-average interest rate for the outstanding borrowings under the revolving credit agreements, commercial paper borrowings and letters of credit.

OG&E must obtain regulatory approval from the FERC in order to borrow on a short-term basis. OG&E has the necessary regulatory approvals to incur up to $1.0 billion in short-term borrowings at any one time for a two-year period beginning January 1, 2025 and ending December 31, 2026.

10. Retirement Plans and Postretirement Benefit Plans

Net Periodic Benefit Cost

The following tables present the net periodic benefit cost components, before consideration of capitalized amounts, of OGE Energy's Pension Plan, Restoration of Retirement Income Plan and postretirement benefit plans that are included in the condensed financial statements. Service cost is presented within Other Operation and Maintenance Expense, and the remaining net periodic benefit cost components as listed in the following tables are presented within Other Net Periodic Benefit Income (Expense) in the statements of income. OG&E recovers specific amounts of pension and postretirement medical costs in rates approved in its Oklahoma rate reviews. In accordance with approved orders, OG&E defers the difference between actual pension and postretirement medical expenses and the amount approved in its last Oklahoma rate review as a regulatory asset or regulatory liability. These amounts have been recorded in the Pension tracker in the regulatory assets and liabilities table in Note 1 and within Other Net Periodic Benefit Income (Expense) in the statements of income.

(A)

Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment.

In addition to the net periodic benefit cost amounts recognized, as presented in the tables above, for the Pension and Restoration of Retirement Income Plans during the three months ended March 31, 2025 and 2024, the Registrants recognized the following:

(A)

Included in the pension regulatory asset in each jurisdiction, as indicated in the regulatory assets and liabilities table in Note 1.

In addition to the net periodic benefit cost amounts recognized, as presented in the table above, for the postretirement benefit plans during the three months ended March 31, 2025 and 2024, the Registrants recognized the following:

(A)

Included in the pension regulatory asset, as indicated in the regulatory assets and liabilities table in Note 1.

The following table presents the amount of net periodic benefit cost capitalized and attributable to each of the Registrants for OGE Energy's Pension Plan and postretirement benefit plans for thethree months ended March 31, 2025 and 2024.

Pension Plan Funding

In January 2025, OGE Energy made a $5.0 million contribution to its Pension Plan related to OG&E employees and expects to make an additional contribution of $5.0 million to the Pension Plan in 2025. The Registrants could be required to make additional contributions if the value of its pension trust and postretirement benefit plan trust assets are adversely impacted by a major market disruption in the future.

11. Report of Business Segments

OGE Energy reports its operations primarily through asingle segment, captioned "electric company," which is engaged in the generation, transmission, distribution and sale of electric energy. The "other operations" caption primarily includes the operations of the holding company and other energy-related investments. Intersegment revenues are recorded at prices comparable to those of unaffiliated customers and are affected by regulatory considerations. The Registrants' chief operating decision maker uses net income as a measure of reportable segment profit or loss to make operating decisions, allocate resources, and assess performance. The following tables, which include significant segment expenses, present the results of OGE Energy's business segments for thethree months ended March 31, 2025 and 2024.

12. Commitments and Contingencies

Except as set forth below, in Note 13 and under "Environmental Laws and Regulations" in Item 2 of Part I and in Item 1 of Part II of this Form 10-Q, the circumstances set forth in Notes 13 and 14 to the financial statements included in the Registrants'2024 Form 10-K appropriately represent, in all material respects, the current status of the Registrants' material commitments and contingent liabilities.

Environmental Laws and Regulations

The activities of OG&E are subject to numerous stringent and complex federal, state and local laws and regulations governing environmental protection. These laws and regulations can change, restrict or otherwise impact the Registrants' business activities in many ways, including the handling or disposal of waste material, planning for future construction activities to avoid or mitigate harm to threatened or endangered species and requiring the installation and operation of emissions or pollution control equipment. Failure to comply with these laws and regulations could result in the assessment of administrative, civil and criminal penalties, the imposition of remedial requirements and the issuance of orders enjoining future operations. Management believes that all of the Registrants' operations are in substantial compliance with current federal, state and local environmental standards.

Environmental regulation can increase the cost of planning, design, initial installation and operation of OG&E's facilities. Management continues to evaluate its compliance with existing and proposed environmental legislation and regulations and implement appropriate environmental programs in a competitive market.

Other

In the normal course of business, the Registrants are confronted with issues or events that may result in a contingent liability. These generally relate to lawsuits or claims made by third parties, including governmental agencies. When appropriate, management consults with legal counsel and other experts to assess the claim. If, in management's opinion, the Registrants have incurred a probable loss as set forth by GAAP, an estimate is made of the loss, and the appropriate accounting entries are reflected in the condensed financial statements. If the assessment indicates that a potential loss is not probable but reasonably possible, the nature of the contingent matter, together with an estimate of the range of possible loss if determinable and material, would be disclosed. At the present time, based on currently available information, except as disclosed below, the Registrants believe that any reasonably possible losses in excess of accrued amounts arising out of pending or threatened lawsuits or claims would not be quantitatively material to their condensed financial statements and would not have a material adverse effect on their financial position, results of operations or cash flows.

In July 2023, OG&E was named, along with its contractor, as a defendant in a lawsuit filed by an apartment owner and its insurance companies seeking in excess of $60.0 millionin damages related to a fire at an apartment building under construction in Oklahoma City. Several additional defendants have also been named. OG&E disputes the claims in the lawsuit and intends to vigorously defend this action. If OG&E is ultimately deemed liable for damages in connection with this incident, OG&E believes its existing insurance policies will cover its costs, in excess of a required retention (the amount of which is not material), to satisfy any liability it may have. Due to the uncertain and preliminary nature of this litigation, the outcome cannot be predicted, and OG&E is unable to provide a range of possible loss in this matter.

13. Rate Matters and Regulation

Except as disclosed below, the circumstances set forth in Note 14 to the financial statements included in the Registrants'2024 Form 10-K appropriately represent, in all material respects, the current status of the Registrants' regulatory matters.

Completed Regulatory Matters

OCC Proceedings

2023 Oklahoma General Rate Review

In December 2023, OG&E filed a general rate review in Oklahoma seeking a rate increase of $332.5 million and a 10.5 percent return on equity based on a common equity percentage of 53.50 percent. The rate review sought recovery of $1.3 billion of capital investment since the last general rate review. Prior to the hearing on the merits, on June 12, 2024, OG&E entered into an uncontested settlement agreement, which was also executed by the OCC Public Utility Division Staff, the Oklahoma Attorney General, the OG&E Shareholders Association, Oklahoma Industrial Energy Consumers and other intervenors. This settlement agreement resulted in an annual revenue requirement increase of $126.7 million. OG&E had the right to implement interim rates subject to refund beginning July 1, 2024 (180 days after the filing of its application on December 29, 2023). On July 1, 2024, OG&E implemented an annual interim rate increase in line with the settlement agreement, subject to refund based on final approval by the OCC.

On November 26, 2024, the OCC issued an interim order approving the settlement agreement. In addition to the annual base rate revenue increase of 126.7 million, other key terms of the uncontested settlement agreement, as approved in the interim order by the OCC, include, among others:

•

All recorded plant-in-service through March 31, 2024 is prudent and should be included in rate base;

•

There will be no change in OG&E's current return on equity of 9.5 percent, and OG&E's requested capital structure based on a common equity percentage of 53.50 percent would be approved;

•

OG&E will utilize depreciation rates based on the recommendations of the Federal Executive Agencies for production plant accounts, the Public Utility Division for transmission plant accounts, Oklahoma Industrial Energy Consumers for intangible plant accounts, and no change to existing rates for distribution and general plant accounts; and

•

OG&E will include in expense any Oklahoma vegetation management operation and maintenance expenses up to $38.2 million annually and defer to a regulatory asset or liability the total level of expense less than or greater than the $38.2 million annual base level of expense. The regulatory asset will be up to $7.5 million in excess of the base rate level and no carrying charge will accrue on the regulatory asset/liability. The costs booked to the regulatory asset or liability will be subject to a prudence review in OG&E’s next general rate review.

Due to the November 26, 2024 OCC interim order approving the settlement agreement, no refund of interim rates was deemed necessary. On March 27, 2025, the OCC issued a final order in this matter, which affirmed its previous order approving the settlement agreement and approved the ALJ report on the remaining one MW issue with one exception. The one exception stated that in its next general rate review, OG&E shall directly assign the costs of transmission radials to new competitive load customers that are added to the system after November 1, 2023. No other changes were made to rates implemented effective July 1, 2024 after the November 26, 2024 interim order. While the OCC’s final order has been appealed, the rates will remain in effect.

2023 Oklahoma Fuel Prudency

On June 10, 2024, the Public Utility Division Staff filed their application initiating the prudence review of the 2023 fuel adjustment clause. The OCC issued an order on April 22, 2025 finding that OG&E's 2023 fuel costs and generation operations were prudent.

Pending Regulatory Matters

Various proceedings pending before state or federal regulatory agencies are described below. Unless stated otherwise, the Registrants cannot predict when the regulatory agency will act or what action the regulatory agency will take. The Registrants' financial results are dependent in part on timely and constructive decisions by the regulatory agencies that set OG&E's rates.

APSC Proceedings

Arkansas Prudence of Horseshoe Lake and Tinker Generation Facilities

On December 30, 2024, pursuant to orders in the generation construction notice filings, OG&E filed an application requesting a determination of prudence of action and initial contract costs for the generating units being constructed at Horseshoe Lake and Tinker Air Force Base. On March 10, 2025, at the request of APSC Staff, OG&E filed supplemental testimony detailing the contracts and additional information about initial costs of the projects.

FERC Proceedings

Order for Sponsored Transmission Upgrades within SPP

Under Attachment Z2 of the SPP Open Access Transmission Tariff, costs of participant-funded, or "sponsored," transmission upgrades may be recovered from other SPP customers whose transmission service depends on capacity enabled by the upgrade. The SPP tariff required the SPP to charge for these upgrades beginning in 2008, but the SPP did not begin charging its customers for these upgrades until 2016 due to information system limitations. The FERC approved a waiver of a time limitation in the SPP tariff to allow the SPP to bill after this delay for the 2008 through 2015 period, and the SPP then both billed OG&E as a user and credited OG&E as a sponsor for Z2 charges during the period. OG&E refunded most of the net credits to customers through its various rate riders that include SPP activity with the remaining amounts retained by OG&E.

Net payers of Z2 credits challenged the waiver, and the FERC ultimately reversed itself, denied the waiver and ordered the SPP to refund the payments made for 2008 through 2015 charges. OG&E and other net creditors challenged this reversal, but the U.S. Court of Appeals for the D.C. Circuit upheld the reversal in August 2021. Meanwhile, OG&E and other creditors filed complaints with the FERC against the SPP, contending that the SPP and not OG&E should bear the cost of any refunds resulting from the SPP's tariff violations and that SPP’s actions also violated its contracts. In June 2023, the FERC issued a final order granting the complaints in part but awarding no relief. OG&E and other complainants appealed this order to the U.S. Court of Appeals for the Eighth Circuit, which heard arguments on March 14, 2024 and on September 16, 2024, the U.S. Court of Appeals for the Eighth Circuit denied relief and upheld the FERC's decision.

If the FERC proceeds to order refunds in full, OG&E estimates it would be required to refund $14.0 million, which is net of amounts paid to other utilities for upgrades, plus interest at the FERC-approved rate. Payment of refunds would shift recovery of these upgrade credits to future periods. The SPP has submitted filings to the FERC outlining a refund process but stating some issues need the FERC's clarification before refunds can proceed. OG&E and other parties have commented on the filings and the matter remains pending before the FERC. Of the $14.0 million, the Registrants would be impacted by $4.0 million in expense that initially benefited the Registrants in 2016, and OG&E customers would incur a net impact of $10.0 million in expense through rider mechanisms or the FERC formula rate. As of March 31, 2025, the Registrants have reserved $14.0 million plus estimated interest for a potential refund.

Effective July 1, 2020, the FERC approved an SPP proposal to eliminate Attachment Z2 revenue crediting and replace it with a different rate mechanism that would provide project sponsors, such as OG&E, the same level of recovery. This elimination of the Attachment Z2 revenue crediting would only prospectively impact OG&E and its recovery of any future upgrade costs that it may incur as a project sponsor subsequent to July 2020. All of the existing projects that are eligible to receive revenue credits under Attachment Z2 will remain eligible, which includes the $14.0 million related to the refunds.

OCC Proceedings

Oklahoma Retail Electric Supplier Certified Territory Act Causes

As previously disclosed, several rural electric cooperative electricity suppliers filed complaints with the OCC alleging that OG&E, because it was providing service to large loads in another supplier's territory, had violated the Oklahoma Retail Electric Supplier Certified Territory Act. OG&E believes it is lawfully serving customers under specific exemptions under this act that allow it to serve customers having a load of one MW or greater. There were five complaint cases initiated at the OCC, and the OCC issued decisions on each of them. The OCC ruled in favor of the electric cooperatives in three of those cases under statutory interpretation and ruled in favor of OG&E in two of those cases under injunctive theory. All five of those cases were appealed to the Oklahoma Supreme Court.

On April 4, 2023, the Oklahoma Supreme Court issued its opinion which vacated the OCC's injunctions with respect to four of the cases and held that the Oklahoma Retail Electric Supplier Certified Territory Act does not limit the mechanism by which OG&E may provide service to large loads in another supplier's territory pursuant to the one MW exception. The one pending legal issue left for the Oklahoma Supreme Court to resolve is a statutory interpretation on how a supplier calculates "connected load for initial full operation" for purposes of the exemption under the act. If the Oklahoma Supreme Court ultimately were to find that the customers being served in this single case are not exempted from the Oklahoma Retail Electric Supplier Certified Territory Act, OG&E would have to evaluate the recoverability of some plant investments made to serve these customers and may also be required to reimburse the certified territory supplier in this case for an amount of lost revenue. Such amounts would not be expected to be material to the Registrants' results of operations.

On March 4, 2025, the Oklahoma Supreme Court issued a decision in one of the other companion cases and reversed itself, finding that OG&E may not “extend service” from third-party transmission facilities. This ruling was prospective in nature, which means OG&E may still serve the customers subject to the ruling, but in the future, OG&E may not extend services off of third-party transmission facilities.

2024 Oklahoma Fuel Prudency

On April 1, 2025, the Public Utility Division Staff filed their application initiating the prudence review of the 2024 fuel adjustment clause. OG&E expects to file its minimum filing requirements and direct testimony no later than June 1, 2025, in accordance with OCC rules.

SPP Proceedings

Resource Capacity Accreditation

In July 2022, the SPP Board of Directors approved a new unit accreditation methodology for conventional generation which requires submittal to and approval from the FERC prior to becoming effective. On March 2, 2023, the FERC rejected the SPP’s proposed capacity accreditation methodology for wind and solar generators. Following the FERC’s rejection, the SPP began an extensive review of both the methodology proposed for thermal resources which had not yet been submitted to the FERC, and the accreditation methodology for wind and solar generators. These methodologies were reviewed and approved by both the Regional State Committee and the SPP Board of Directors in late October 2023 and were submitted to the FERC for approval on February 23, 2024. On January 16, 2025, the FERC accepted the SPP's proposed tariff revisions for each accreditation methodology to become effective October 1, 2025. OG&E is evaluating the impact of the FERC's acceptance of these accreditation methods, which may contribute to OG&E’s capacity needs.