OGE ENERGY CORP

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31,2023

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

321 North Harvey

P.O. Box 321

Oklahoma City, Oklahoma 73101-0321

405-553-3000

State or other jurisdiction of incorporation or organization: Oklahoma

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act.

OGE Energy Corp. ☐ Yes ☑No Oklahoma Gas and Electric Company ☐ Yes ☑ No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.

OGE Energy Corp.☑ Oklahoma Gas and Electric Company☑

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

OGE Energy Corp.☐ Yes ☑ No Oklahoma Gas and Electric Company☐ Yes ☑ No

At June 30, 2023, the last business day of OGE Energy Corp.'s most recently completed second fiscal quarter, the aggregate market value of shares of common stock held by non-affiliates was $7,192,319,241 based on the number of shares held by non-affiliates (200,287,364) and the reported closing market price of the common stock on the New York Stock Exchange on such date of $35.91.

At June 30, 2023, there was no voting or non-voting common equity of Oklahoma Gas and Electric Company held by non-affiliates.

At January 31, 2024, there were 200,330,340 shares of OGE Energy Corp.'s common stock, par value $0.01 per share, outstanding.

At January 31, 2024, there were 40,378,745 shares of Oklahoma Gas and Electric Company's common stock, par value $2.50 per share, outstanding, all of which were held by OGE Energy Corp. There were no other shares of capital stock of the registrant outstanding at such date.

DOCUMENTS INCORPORATED BY REFERENCE

The Proxy Statement for OGE Energy Corp.'s 2024 annual meeting of shareowners is incorporated by reference into Part III of this Form 10-K.

This combined Form 10-K represents separate filings by OGE Energy Corp. and Oklahoma Gas and Electric Company. Information contained herein related to an individual registrant is filed by such registrant on its own behalf. Oklahoma Gas and Electric Company makes no representations as to the information relating to OGE Energy Corp.'s other operations.

Oklahoma Gas and Electric Company meets the conditions set forth in General Instruction I(1)(a) and (b) of Form 10-K and is therefore filing this form with the reduced disclosure format permitted by General Instruction I(2).

FORM 10-K

FOR THE YEAR ENDED DECEMBER 31, 2023

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