UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No.                 )

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Midcap Financial Investment Corporation

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Your Vote Counts! MIDCAP FINANCIAL INVESTMENT CORPORATION 2023 Annual Meeting Vote by July 9, 2023 11:59 PM ET MIDCAP FINANCIAL INVESTMENT CORPORATION 9 W 57TH STREET NEW YORK, NY 10019 V16853-P92606 You invested in MIDCAP FINANCIAL INVESTMENT CORPORATION and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy material for the stockholder meeting to be held on July 10, 2023. Get informed before you vote View the Notice and Proxy Statement and 10-K Wrap online OR you can receive a free paper or email copy of the material(s) by requesting prior to June 26, 2023. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. For complete information and to vote, visit www.ProxyVote.com Control # Smartphone users Vote Virtually at the Meeting* Point your camera here and July 10, 2023 10:00 a.m., Eastern Daylight Time vote without entering a control number Virtually at: www.virtualshareholdermeeting.com/MFIC2023 *Please check the meeting materials for any special requirements for meeting attendance. V1.1

Vote at www.ProxyVote.com THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. Voting Items Board Recommends 1. Election of Directors Nominees: For 01) Emanuel Pearlman 02) Howard Widra 2. To ratify the selection of Deloitte & Touche LLP as Midcap Financial Investment Corporation’s (the “Company”) For independent registered public accounting firm for the fiscal year ending December 31, 2023. NOTE: Such other business as may properly come before the meeting or any adjournment thereof. Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Delivery Settings”. V16854-P92606