Filed by Goldman Sachs BDC, Inc.

pursuant to Rule 425 under the Securities Act of 1933

and deemed filed under Rule 14a-6(b) of the Securities Exchange Act of 1934

Subject Company: Goldman Sachs Middle Market Lending Corp.

File No. of Related Registration Statement: 333-235856

Solicitation Script

Goldman Sachs BDC, Inc. & Goldman Sachs Middle Market Lending Corp.

833-670-0593

Meeting Date: October 2, 2020

Inbound Greeting:

Thank you for calling the Broadridge Proxy Services Center for Goldman Sachs BDC and Middle Market Lending Corp. My name is <Agent Name>. How may I assist you today and can you please state whether you are calling as a stockholder of Goldman Sachs BDC, Inc. or Goldman Sachs Middle Market Lending Corp.?

General Outbound Greeting:

Good day, may I please speak with Mr./Ms. <full name as it appears on registration>?

Hello Mr./Ms. <Stockholder’s Last Name>. My name is <agent name> and I am a proxy voting specialist calling on behalf of <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> to confirm you have received the proxy materials for the Special Meeting of Stockholders scheduled for October 2, 2020. Have you received proxy materials?

Near Meeting Date Outbound Greeting:

Good day, may I please speak with Mr./Ms. <full name as it appears on registration>?

Hello Mr./Ms.<last name>. My name is <agent name> and I am a proxy voting specialist calling on behalf of <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> to confirm you have received the proxy materials for the Special Meeting of Stockholders scheduled in just a few days on October 2, 2020. Have you received proxy materials?

Adjournment Outbound Greeting:

Good day, may I please speak with Mr./Ms. <full name as it appears on registration>?

Hi Mr. /Ms.                 , my name is <Agent Name> and I am a proxy voting specialist calling on behalf of <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> Due to the lack of stockholder participation, the Special Meeting of Stockholders has been adjourned to <date/time>. Have you received proxy materials?

Voting:

Your board has recommended a vote IN FAVOR of the proposal. Would you like to vote along with the recommendations of the board for all of your accounts?

Thank you, I am recording your <for, against, abstain> vote. For confirmation purposes, please state your full name.

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And according to our records, you currently reside in <read street address, city, and state > is that correct? For confirmation purposes, please state your zip code.

Thank you. You will receive a confirmation of your voting instructions within 5 days. If you have any questions, please contact us at this toll free number 833-670-0593.

Mr./Ms. <Stockholder’s Last Name>, your vote is important, and your time is appreciated. Thank you and have a good <day, evening, night>.

If Unsure of voting or does not want to vote along with the recommendation of the Board:

Would you like me to review the proposal with you? <After review, ask them if they would like to vote now over the phone>.

If not received/Requesting material to be re-mailed:

I can resend the proxy materials to you, or I can review the proposal with you and record your vote immediately by phone. <Pause for response>

After review, ask them if they would like to vote now over the phone:

Your Board recommends that you vote “FOR” the proposal. Would you like to vote along with the recommendations of the Board for all your accounts?

If they don’t want proposal reviewed:

Do you have an email address this can be sent to? <If yes, enter the email address in the notes and read it back phonetically to the stockholder.>

Thank you. You should receive the proxy materials shortly and the materials will inform you of the methods available to cast your vote, one of which is to call us back at 833-670-0593.

If Not Interested:

I am sorry for the inconvenience. Please be aware that as a stockholder, your vote is very important. Please fill out and return your proxy card at your earliest convenience. If you would rather not do that, you can always vote via the other methods outlined in the proxy materials. Thank you again for your time today, and have a wonderful day/evening.

Registered holder wants a new proxy card/or their control number <send complete contact information name, address, control #, & shares to Broadridge>:

Your control number can be found on your proxy card. I can arrange to have a new proxy card sent to you. However, I can record your voting instructions right now so that it will be represented at the upcoming meeting. Your board is recommending you vote FOR the proposals…

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Beneficial holder wants a new VIF/or their control number:

Your control number can be found on your Vote Instruction Form. You can contact your broker/financial advisor and they can arrange to have a new voting instruction form sent to you. However, I can record your voting instructions right now so that it will be represented at the upcoming meeting. Your board is recommending you vote FOR the proposal…

ANSWERING MACHINE MESSAGE:

Hello, my name is <Agent Name> and I am a proxy voting specialist calling on behalf of <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> You should have received proxy material electronically or in the mail concerning the Special Meeting of Stockholders to be held on October 2, 2020.

Your vote is very important. Please sign, date and promptly mail your proxy card in the postage-paid envelope provided. Internet and telephone voting are also available. To vote over the Internet please follow the instructions provided in the proxy materials. If you have any questions, would like to vote over the telephone or need new proxy materials, please call toll-free at 833-670-0593 and a proxy voting specialist will assist you. That number again is 833-670-0593. Specialists are available Monday through Friday, 9AM to 10PM Eastern Time. Voting takes just a few moments and will benefit all stockholders. Thank you for your prompt attention to this matter.

AUTOMATED ANSWERING MACHINE MESSAGE:

Hello, this is the Broadridge Proxy Services Center calling with an important message on behalf of <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> You should have received proxy material electronically or in the mail concerning the Special Meeting of Stockholders to be held on October 2, 2020.

Your vote is very important. Please sign, date and promptly mail your proxy card in the postage-paid envelope provided. Internet and telephone voting are also available. To vote over the Internet please follow the instructions provided in the proxy materials. If you have any questions, would like to vote over the telephone or need new proxy materials, please call toll-free at 833-670-0593 and a proxy voting specialist will assist you. That number again is 833-670-0593. Specialists are available Monday through Friday, 9AM to 10PM Eastern Time. Voting takes just a few moments and will benefit all stockholders. Thank you for your prompt attention to this matter.

FUND RECORDED ANSWERING MACHINE MESSAGE 1:

Hello, this is <Fund Representative> calling you with an important message concerning your investment with <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.>

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You should have received proxy material electronically or in the mail concerning the special Meeting of Stockholders to be held on October 2, 2020.

Your vote is very important. Please sign, date and promptly mail your proxy card in the postage-paid envelope provided. Internet and telephone voting are also available. To vote over the Internet please follow the instructions provided in the proxy materials. If you have any questions, would like to vote over the telephone or need new proxy materials, please call toll-free at 833-670-0593 and a proxy voting specialist will assist you. That number again is 833-670-0593. Specialists are available Monday through Friday, 9AM to 10PM Eastern Time. Voting takes just a few moments and will benefit all stockholders. Thank you for your prompt attention to this matter.

FUND RECORDED ANSWERING MACHINE MESSAGE 2:

Hello, this is <Fund Representative> calling you with an important message concerning your investment with <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> You should have received proxy material electronically or in the mail concerning the Special Meeting of Stockholders to be held on October 2, 2020. The meeting date is fast approaching and we need your help.

Your vote is very important. Please sign, date and promptly mail your proxy card in the postage-paid envelope provided. Internet and telephone voting are also available. To vote over the Internet please follow the instructions provided in the proxy materials. If you have any questions, would like to vote over the telephone or need new proxy materials, please call toll-free at 833-670-0593 and a proxy voting specialist will assist you. That number again is 833-670-0593. Specialists are available Monday through Friday, 9AM to 10PM Eastern Time. Voting takes just a few moments and will benefit all stockholders. Thank you for your prompt attention to this matter.

FUND RECORDED ANSWERING MACHINE MESSAGE 3:

Hello, this is <Fund Representative> calling you with an urgent message concerning your investment with <Goldman Sachs BDC, Inc. / Goldman Sachs Middle Market Lending Corp.> You have probably received several messages concerning this Special Meeting either electronically, by mail or by phone. That is because the meeting date is just a few days away on October 2, 2020 and we need your help.

Your vote is very important. Please sign, date and promptly mail your proxy card in the postage-paid envelope provided. Internet and telephone voting are also available. To vote over the Internet please follow the instructions provided in the proxy materials. If you have any questions, would like to vote over the telephone or need new proxy materials, please call toll-free at 833-670-0593 and a proxy voting specialist will assist you. That number again is 833-670-0593. Specialists are available Monday through Friday, 9AM to 10PM Eastern Time. Voting takes just a few moments and will benefit all stockholders. Thank you for your prompt attention to this matter.

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INBOUND - CLOSED RECORDING:

Thank you for calling the Broadridge Proxy Services Center. Our offices are now closed. Please call us back during our normal business hours which are, Monday through Friday, 9AM to 10PM Eastern Time. Thank you.

INBOUND - CALL IN QUEUE MESSAGE:

Thank you for calling the Broadridge Proxy Services Center. Our proxy specialists are currently assisting other stockholders. Your call is important to us. Please continue to hold and your call will be answered in the order in which it was received.

END OF CAMPAIGN MESSAGE:

Thank you for calling the Broadridge Proxy Services Center. The Stockholder meeting has been held and as a result, this toll-free number is no longer in service for proxy related calls. If you have questions about your investment, please contact your Financial Advisor or the fund company directly. Thank you and have a nice day.

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Forward-Looking Statements

This communication may contain “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Statements other than statements of historical facts included in this communication may constitute forward-looking statements and are not guarantees of future performance or results of Goldman Sachs BDC, Inc. (“GSBD”), Goldman Sachs Middle Market Lending Corp. (“MMLC”), or, following the merger, the combined company and involve a number of risks and uncertainties. Such forward-looking statements may include statements preceded by, followed by or that otherwise include the words “may,” “might,” “will,” “intend,” “should,” “could,” “can,” “would,” “expect,” “believe,” “estimate,” “anticipate,” “predict,” “potential,” “plan” or similar words. Actual results may differ materially from those in the forward-looking statements as a result of a number of factors, including those described from time to time in filings made by GSBD and MMLC with the Securities and Exchange Commission (“SEC”), including those contained in the Proxy Statement (as defined below). Certain factors could cause actual results to differ materially from those projected in these forward-looking statements. Factors that could cause actual results to differ materially include: the ability of the parties to consummate the merger on the expected timeline, or at all, failure of GSBD or MMLC to obtain the requisite stockholder approval for the Proposals (as defined below) as set forth in the Proxy Statement, the ability to realize the anticipated benefits of the merger, effects of disruption on the business of GSBD and MMLC from the proposed merger, the effect that the announcement or consummation of the merger may have on the trading price of GSBD’s common stock on New York Stock Exchange; the combined company’s plans, expectations, objectives and intentions as a result of the merger, any decision by MMLC to pursue continued operations, any termination of the Amended and Restated Agreement and Plan of Merger, future operating results of GSBD or MMLC, the business prospects of GSBD and MMLC and the prospects of their portfolio companies, actual and potential conflicts of interests with Goldman Sachs Asset Management, L.P. (“GSAM”) and other affiliates of GSAM, general economic and political trends and other factors, the dependence of GSBD’s and MMLC’s future success on the general economy and its effect on the industries in which they invest; and future changes in laws or regulations and interpretations thereof. Neither GSBD nor MMLC undertakes any duty to update any forward-looking statement made herein. All forward-looking statements speak only as of the date of this communication.

Additional Information and Where to Find It

This communication relates to a proposed business combination involving GSBD and MMLC, along with related proposals for which stockholder approval will be sought (collectively, the “Proposals”). In connection with the Proposals, each of GSBD and MMLC has filed relevant materials with the SEC, including a registration statement on Form N-14, which includes a joint proxy statement of GSBD and MMLC and a prospectus of GSBD (the “Proxy Statement”). The Proxy Statement was mailed to stockholders of GSBD and MMLC on or about August 11, 2020. This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act. STOCKHOLDERS OF EACH OF GSBD AND MMLC ARE URGED TO READ CAREFULLY AND IN THEIR ENTIRETY ALL RELEVANT DOCUMENTS FILED WITH THE SEC, INCLUDING THE PROXY STATEMENT, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS THERETO, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT GSBD, MMLC, THE MERGER AND THE PROPOSALS. Investors and security holders will be able to obtain the documents filed with the SEC free of charge at the SEC’s web site, http://www.sec.gov or, for documents filed by GSBD, from GSBD’s website at http://www.GoldmanSachsBDC.com.

Participants in the Solicitation

GSBD and MMLC and their respective directors, executive officers and certain other members of management and employees of GSAM and its affiliates, may be deemed to be participants in the solicitation of proxies from the stockholders of GSBD and MMLC in connection with the Proposals. Information about the directors and executive officers of GSBD and MMLC is set forth in the Proxy Statement. Information regarding the persons who may, under the rules of the SEC, be considered participants in the solicitation of the GSBD and MMLC stockholders in connection with the Proposals are contained in the Proxy Statement and other relevant materials filed with the SEC. This document may be obtained free of charge from the sources indicated above.