TortoiseEcofin Acquisition Corp. III (TRTLF) SC 13G/ATortoiseEcofin Acquisition Corp. III / Linden Capital ownership change

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

TortoiseEcofin Acquisition Corp. III

(Name of Issuer)

Class A ordinary shares, par value $0.0001 per share

(Title of Class of Securities)

G8956E109

(CUSIP Number)

December 31, 2023

(Date of Event which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(Continued on the Following Pages)

(Page 1 of 7 Pages)

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This Amendment No. 2 (“Amendment No. 2”) is filed pursuant to Rule 13d-2(b) promulgated under the Securities Exchange Act of 1934, as amended, with respect to the Class A ordinary shares, par value $0.0001 per share (the “Shares”), of TortoiseEcofin Acquisition Corp. III (the “Issuer”) beneficially owned by the Reporting Persons specified herein as of December 31, 2023, and amends and supplements the Schedule 13G filed July 28, 2021 as amended by Amendment No. 1 thereto filed February 3, 2022 (collectively, the “Schedule 13G”). Except as set forth herein, the Schedule 13G is unmodified.

The names of the persons filing this statement on Amendment No. 2 are: Linden Capital L.P., a Bermuda limited partnership (“Linden Capital”), Linden Advisors LP, a Delaware limited partnership (“Linden Advisors”), Linden GP LLC, a Delaware limited liability company (“Linden GP”), and Mr. Siu Min (Joe) Wong (“Mr. Wong,” and collectively, the “Reporting Persons”).

As of December 31, 2023, the Reporting Persons have ceased to be the beneficial owner of more than five percent of the outstanding Shares.

If this statement is being filed to report the fact that as of the date hereof the Reporting Persons have ceased to be the beneficial owner of more than five percent of the class of securities, check the following ☒.

By signing below, the undersigned certifies that, to the best of its knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under Sec. 240.14a-11.

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SIGNATURES

After reasonable inquiry and to the best of its knowledge and belief, each of the undersigned certifies that the information with respect to it set forth in this statement is true, complete, and correct.

Dated: February 6, 2024