Oaktree Specialty Lending : and Oaktree Strategic Income Corporation Merger Investor Presentation

Merger of

OCSL & OCSI

October 29, 2020

Investor Presentation

Disclaimer

Forward-Looking Statements

Some of the statements in this presentation constitute forward-looking statements because they relate to future events, future performance or financial condition or the two-step merger (the "mergers") of Oaktree Strategic Income Corporation ("OCSI") with and into Oaktree Specialty Lending Corporation ("OCSL"). The forward-looking statements may include statements as to: future operating results of OCSI and OCSL and distribution projections; business prospects of OCSI and OCSL and the prospects of their portfolio companies; and the impact of the investments that OCSI and OCSL expect to make. In addition, words such as "anticipate," "believe," "expect," "seek," "plan," "should," "estimate," "project" and "intend" indicate forward- looking statements, although not all forward-looking statements include these words. The forward-looking statements contained in this presentation involve risks and uncertainties. Certain factors could cause actual results and conditions to differ materially from those projected, including the uncertainties associated with (i) the timing or likelihood of the Mergers closing; (ii) the expected synergies and savings associated with the Mergers; (iii) the expected elimination of certain expenses and costs due to the Mergers; (iv) the percentage of OCSI and OCSL stockholders voting in favor of the proposals submitted for their approval; (v) the ability to realize the anticipated benefits of the mergers, including possibility that competing offers or acquisition proposals will be made; (vi) the possibility that any or all of the various conditions to the consummation of the Mergers may not be satisfied or waived; (vii) risks related to diverting management's attention from ongoing business operations; (viii) the risk that stockholder litigation in connection with the Mergers may result in significant costs of defense and liability; (ix) changes in the economy, financial markets and political environment, (x) risks associated with possible disruption in the operations of OCSI and OCSL or the economy generally due to terrorism, natural disasters or the COVID-19 pandemic; (xi) future changes in laws or regulations (including the interpretation of these laws and regulations by regulatory authorities); (xii) conditions in OCSI's and OCSL's operating areas, particularly with respect to business development companies or regulated investment companies; (xiii) general considerations associated with the COVID-19 pandemic; and (xiv) other considerations that may be disclosed from time to time in OCSI's and OCSL's publicly disseminated documents and filings. OCSI and OCSL have based the forward-looking statements included in this presentation on information available to them on the date of this presentation, and they assume no obligation to update any such forward-looking statements. Although OCSI and OCSL undertake no obligation to revise or update any forward-looking statements, whether as a result of new information, future events or otherwise, you are advised to consult any additional disclosures that they may make directly to you or through reports that OCSI and OCSL in the future may file with the Securities and Exchange Commission ("SEC"), including the Joint Proxy Statement and the Registration Statement (each as defined below), annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

Additional Information and Where to Find It

In connection with the Mergers, OCSI and OCSL plan to file with the SEC and mail to their respective stockholders a joint proxy statement on Schedule 14A (the "Joint Proxy Statement"), and OCSL plans to file with the SEC a registration statement on Form N-14 (the "Registration Statement") that will include the Joint Proxy Statement and a prospectus of OCSL. The Joint Proxy Statement and the Registration Statement will each contain important information about OCSI, OCSL, the Mergers and related matters. 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 of 1933, as amended. STOCKHOLDERS OF OCSI AND OCSL ARE URGED TO READ THE JOINT PROXY STATEMENT AND REGISTRATION STATEMENT, AND OTHER DOCUMENTS THAT ARE FILED OR WILL BE FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THESE DOCUMENTS, CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT OCSI, OCSL, THE MERGERS AND RELATED MATTERS. Investors and security holders will be able to obtain the documents filed with the SEC free of charge at the SEC's website, http://www.sec.gov or, for documents filed by OCSI, from OCSI's website at http://www.oaktreestrategicincome.com and, for documents filed by OCSL, from OCSL's website at http://www.oaktreespecialtylending.com.

Participants in the Solicitation

OCSI, its directors, certain of its executive officers and certain employees and officers of Oaktree Fund Advisors, LLC and its affiliates (collectively, "Oaktree") may be deemed to be participants in the solicitation of proxies in connection with the Mergers. Information about the directors and executive officers of OCSI is set forth in its proxy statement for its 2020 Annual Meeting of Stockholders, which was filed with the SEC on January 13, 2020. OCSL, its directors, certain of its executive officers and certain employees and officers of Oaktree, LLC and its affiliates may be deemed to be participants in the solicitation of proxies in connection with the Mergers. Information about the directors and executive officers of OCSL is set forth in its proxy statement for its 2020 Annual Meeting of Stockholders, which was filed with the SEC on January 13, 2020. Information regarding the persons who may, under the rules of the SEC, be considered participants in the solicitation of the OCSI and OCSL stockholders in connection with the Mergers will be contained in the Joint Proxy Statement when such document becomes available. These documents may be obtained free of charge from the sources indicated above.

No Offer or Solicitation

This presentation is not, and under no circumstances is it to be construed as, a prospectus or an advertisement and the communication of this presentation is not, and under no circumstances is it to be construed as, an offer to sell or a solicitation of an offer to purchase any securities in OCSI, OCSL or in any fund or other investment vehicle managed by Oaktree.

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Key Transaction Benefits

OCSL

Expected to be accretive to NII

Increase in first lien investments

May gain greater access to debt capital markets

Increased scale with $2+ billion of assets and improved secondary market liquidity

Acquisition of a known, diversified portfolio

OCSI

Expected to be accretive to NII

Increase in portfolio yield

Benefit from OCSL's investment grade credit ratings and unsecured debt

Increased equity research coverage and secondary market liquidity

Dividend accretion

The board of directors of each of OCSL and OCSI have unanimously approved the merger and believe

that it will create significant value for stockholders of both companies1

1 In connection with the consideration of a transaction, the board of directors of each OCSL and OCSI established a special committee, consisting only of certain independent directors. The board of directors of each of OCSL and OCSI unanimously approved the merger following the unanimous recommendation of the OCSL Special Committee and OCSI Special Committee, respectively.

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Transaction Summary

Merger Consideration

Pro Forma

Balance Sheet

Fee Structure

Required Approvals

Management &

Governance

Expected Timing

As of June 30, 2020

• Stock-for-stockmerger with an exchange ratio determined at closing such that the issuance of OCSL shares to OCSI shareholders will result in ownership of the combined company proportional to each of OCSL's and OCSI's respective net asset values at closing
• Combined company to continue to trade under the ticker symbol "OCSL" on the Nasdaq Global Select Market
• $2.2 billion of total assets, $1.1 billion of net assets
• Investments in 148 portfolio companies
• Pro forma leverage of 0.89x debt-to-equity; no anticipated change to OCSL's target leverage ratio of 0.85x to 1.00x
• Flexible capital structure with no near-term debt maturities; OCSL's 2025 Notes and credit facilities will remain outstanding, and OCSI's credit facilities will be assumed by OCSL
• OCSL base management fee rate of 1.50% to remain unchanged
• OCSL 17.5% incentive fee and 6% hurdle rate to remain unchanged
• Oaktree will waive base management fees equal to $6 million for two years ($0.75 million per quarter for each of the eight quarters) immediately following the closing of the merger
• OCSL: Affirmative vote of a majority of votes cast where a quorum is present
• OCSI: Affirmative vote of a majority of outstanding shares
• Regulatory approvals and other customary closing conditions
• Oaktree will continue to serve as the investment adviser of the combined company
• OCSL's board of directors expected to remain unchanged
• Expect to file preliminary joint proxy by late November 2020
• Anticipate closing in fiscal Q2 2021, subject to stockholder approval and satisfaction or waiver of other closing conditions

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