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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 12b-25

NOTIFICATION OF LATE FILING

(Check One): ☐ Form 10-K ☐ Form 20-F ☐ Form 11-K ⌧ Form 10-Q ☐ Form 10-D☐ Form N-CEN ☐ Form N-CSR

If the notification relates to a portion of the filing checked above, identify the item(s) to which the notification relates:

PART I-REGISTRANT INFORMATION

PART II-RULE 12b-25 (b) AND (c)

If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed. (Check box if appropriate.)

(a)

The reasons described in reasonable detail in Part III of this form could not be eliminated without unreasonable effort or expense;

☒

(b)

The subject annual report, semi-annual report, transition report on Form 10-K, Form 20-F, Form 11-K, FORM N-CEN or Form N- CSR, or portion thereof will be filed on or before the fifth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q, or subject distribution report on Form 10-D, or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date; and

(c)

The accountant's statement or other exhibit required by Rule 12b-25(c) has been attached if applicable.

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PART III - NARRATIVE

State below in reasonable detail why Form 10-K, 20-F, 11-K, 10-Q, 10-D, N-CEN, N-CSR, or the transition report or portion thereof, could not be filed within the prescribed time period.

RMG Acquisition Corp. III (the “Company”) has determined that it is unable, without unreasonable effort or expense, to file its Quarterly Report on Form 10-Q for the quarter ended March 31, 2023 (the “Quarterly Report”) by the prescribed due date for the reasons described below.

The Company is unable to timely file, without unreasonable effort and expense, the Quarterly Report, because additional time is necessary to complete the review of the Quarterly Report and of the financial statements for the quarter ended March 31, 2023.

The Company intends to file the Quarterly Report promptly within the extension period of 5 calendar days as provided under Rule 12b-25 under the Securities Exchange Act of 1934, as amended.

This notification of late filing contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Statements in this filing about the Company that are not historical facts are forward-looking statements based on the Company’s current expectations, assumptions, estimates and projections. These forward-looking statements are subject to risks and uncertainties that could cause actual future events or results to differ materially from such statements. These forward-looking statements are based on our current expectations, which may not prove to be accurate. The words “believe,” “may,” “will,” “estimate,” “potential,” “continue,” “anticipate,” “intend,” “expect,” “could,” “would,” “project,” “plan,” “target” and similar expressions are intended to identify forward-looking statements. These forward-looking statements include, but are not limited to, statements regarding the Company’s beliefs and expectations relating to the filing of the Annual Report and the results of the ongoing review. Important factors that may cause actual results to differ materially from those in the forward-looking statements include, but are not limited to, a material delay in the Company’s financial reporting, including the possibility that the Company will not be able to file its Annual Report within the 5-day extension permitted by the rules of the Securities and Exchange Commission, and the possibility that the ongoing review may identify errors or control deficiencies in the Company’s accounting practices. The Company disclaims and does not undertake any obligation to update or revise any forward-looking statement in this report, except as required by applicable law or regulation.

PART IV - OTHER INFORMATION

(1) Name and telephone number of person to contact in regard to this notification.

(2)  Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If the answer is no, identify report(s). ⌧ Yes ☐ No

(3)  Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof? ☐ Yes ⌧ No

If so, attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made.

has caused this notification to be signed on its behalf by the undersigned thereunto duly authorized.