SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 4)*

The Oncology Institute, Inc.

(Name of Issuer)

Common Stock, par value of $0.0001 per share

(Title of Class of Securities)

23343Q100

(CUSIP Number)

Christopher Kersey

Manager

2100 McKinney Ave, Suite 1760

Dallas, Texas 75201

Tel: (214) 420-3481

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

December 28, 2023

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box:  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

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 following pages)

Common Stock CUSIP No. 23343Q100

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Common Stock CUSIP No. 23343Q100

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Common Stock CUSIP No. 23343Q100

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Explanatory Note

The following constitutes Amendment No. 4 (“Amendment No. 4”) to the Schedule 13D filed by the undersigned with the Securities and Exchange Commission (the “SEC”) on November 22, 2021 (the “Original Schedule 13D”). This Amendment No. 4 amends the Original Schedule 13D as specifically set forth herein.

Item 2. Identity and Background.

Paragraph (a) of Item 2 is hereby amended and restated as follows:

(a) This Amendment No. 4 is being jointly filed by Havencrest Healthcare Partners, L.P., Havencrest Healthcare Partners GP, LLC, and TOI HC I, LLC (each a “Reporting Person” and collectively, the “Reporting Persons”). The name, residence, or principal business address, citizenship, and present principal occupation of each officer or manager of each Reporting Person, as applicable (each, a “Listed Person”), is listed on the updated Schedule I attached hereto.

The agreement among the Reporting Persons to file jointly in accordance with the provisions of Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended (the “Act”) was filed as Exhibit 1.1 to the Original Schedule 13D. Information with respect to each Reporting Person is given solely by such Reporting Person, and no Reporting Person assumes responsibility for the accuracy or completeness of the information furnished by another Reporting Person.

Item 5. Interest in Securities of the Issuer.

Paragraphs (a) and (c) of Item 5 are hereby amended and restated as follows:

(a) Based on the 73,748,979 shares of the Issuer’s Common Stock outstanding as of November 3, 2023, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the SEC on November 8, 2023, the shares of Common Stock held by the Reporting Persons constitute 12.04% of the outstanding shares of Common Stock of the Issuer.

Each Reporting Person disclaims beneficial ownership of the reported Common Stock except to the extent of such Reporting Person’s pecuniary interest therein, and this statement shall not be deemed an admission that such Reporting Person is the beneficial owner of the reported Common Stock for the purposes of Section 13(d) of the Act or any other purpose.

The shares of the Issuer’s Common Stock reported in this Item 5 do not include the Earnout Shares described in Item 3 above.

(c) The information contained in Item 4 is incorporated by reference herein. Except as set forth below or as disclosed herein, none of the Reporting Persons, or to the Reporting Persons’ knowledge, the persons set forth on Schedule I of this Amendment No. 4 has effected transactions in the Common Stock in the past 60 days.

On December 28, 2023, TOI HC I, LLC distributed an aggregate of 4,561,050 shares of the Issuer’s Common Stock in a pro-rata in-kind distribution to its members in accordance with the governing documents of TOI HC I, LLC (the “TOI HC I Distribution”).

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Also on December 28, 2023, following the TOI HC I Distribution, Havencrest Healthcare Partners GP, LLC, on behalf of Havencrest Healthcare Partners, L.P., made a further pro-rata in-kind distribution of the 3,999,998 shares Havencrest Healthcare Partners, L.P. received in the TOI HC I Distribution to Havencrest Healthcare Partners, L.P.’s limited partners in accordance with the governing documents of Havencrest Healthcare Partners, L.P.

Item 7. Material to be Filed as Exhibits.

Item 7 of the Original Schedule 13D is hereby amended to add the following exhibit:

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SCHEDULE I

Havencrest Healthcare Partners, L.P.

The business and operations of Havencrest Healthcare Partners, L.P. are managed by its general partner, Havencrest Healthcare Partners GP, LLC, as set forth below.

Havencrest Healthcare Partners GP, LLC

The name, function, citizenship, and present principal occupation or employment for the officers of Havencrest Healthcare Partners GP, LLC are set forth below. Unless otherwise indicated below, the business address of each officer listed below is 2100 McKinney Avenue, Suite 1760, Dallas, TX 75201.

TOI HC I, LLC

The name, function, citizenship, and present principal occupation or employment for the managers of TOI HC I, LLC are set forth below. Unless otherwise indicated below, (i) each occupation set forth opposite the individual’s name refers to employment with Havencrest Healthcare Partners, L.P. and (ii) the business address of each manager listed below is 2100 McKinney Avenue, Suite 1760, Dallas, TX 75201.

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Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

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