
We have entered into an equity distribution agreement, dated November10, 2022, as amended on August11, 2023, February29, 2024, and March2, 2026 (the “Equity Distribution Agreement”), with RaymondJames& Associates, Inc. and B. Riley Securities, Inc. (each a “Sales Agent” and, collectively the “Sales Agents”), relating to the shares of our common stock offered by this prospectus supplement and theaccompanying prospectus (the “ATM Program). The Equity Distribution Agreement provides that we may offer and sell up to $400,000,000 of shares of our common stock from time to time through the Sales Agents inthe ATM Program. Sales of shares of our common stock, if any, under this prospectus supplement and the accompanying prospectus may be made in negotiated transactions or transactions that are deemed to be “at themarket,” as defined in Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”), including, without limitation, sales made directly on or through the Nasdaq Global Select Market or similar securitiesexchange or sales made to or through a market maker other than on an exchange, at prices related to the prevailing market prices or at negotiated prices, but not at prices below the then current net asset value (“NAV”)per share of our common stock. Our Adviser may, from time to time, in its sole discretion, pay some or all of the Sale Agents’ commission in order to ensure that the sales price per share of our common stock inconnection with all of the offerings made hereunder will not be less than the then current NAV per share of our common stock. Any such payments made by the Adviser will not be subject to reimbursement by us. Under the terms of the Equity Distribution Agreement, the Sales Agents will receive a commission from us of up to 1.50% of the gross sales price of any shares of our common stock sold through the Sales Agentsunder the Equity Distribution Agreement. The Sales Agents are not required to sell any specific number or dollar amount of common stock, but will use their commercially reasonable efforts consistent with their salesand trading practices to sell the shares of our common stock offered by this prospectus supplement and the accompanying prospectus. See “Plan of Distribution” in this prospectus supplement. Our common stock is traded on the Nasdaq Global Select Market under the symbol “FDUS.” On February26, 2026, the official close price of our common stock on the Nasdaq Global Select Market was $18.40per share. The NAV per share of our common stock at December31, 2025 (the last date prior to the date of this prospectus supplement on which we determined NAV) was $19.55. Shares of closed-end investment companies, including BDCs, frequently trade at a discount to their NAV. If our shares trade at a discount to our NAV, it will likely increase the risk of loss forpurchasers in this offering. We are not generally able to issue and sell our common stock at a price below NAV per share. We may, however, sell our common stock, warrants, or rights to acquire ourcommon stock, at a price below then-current NAV per share of our common stock if our board of directors determines that such sale is in our best interests, and if our stockholders approve such sale. At our2025 annual meeting of stockholders, our stockholders voted to allow us to sell or otherwise issue common stock at a price below NAV per share for the period ending on the earlier of the one yearanniversary of the date of our 2025 annual meeting of stockholders and the date of our 2026 annual meeting of stockholders. Accordingly, the authorization will expire on June11, 2026. The proposalapproved by our stockholders did not specify a maximum discount below NAV at which we are able to issue our common stock, although the cumulative number of shares sold pursuant to suchauthorization may not exceed 25% of our outstanding common stock immediately prior to each such sale. In addition, we cannot issue shares of our common stock below NAV unless our board of directorsdetermines that it would be in our and our stockholders’ best interests to do so. Sales of common stock at prices below NAV per share dilute the interests of existing stockholders, have the effect of reducingour NAV per share and may reduce our market price per share. In addition, continuous sales of common stock below NAV may have a negative impact on total returns and could have a negative impact onthe market price of our shares of common stock. Notwithstanding the foregoing authorization, we will not issue shares of our common stock below the then current NAV per share of our common stock inconnection with this offering. See “Sales of Common Stock Below Net Asset Value” in the accompanying prospectus. Investing in our common stock involves risks. Before making a decision to invest in our common stock, you should carefully consider the matters discussed under “Risk Factors” beginning on page 9of the accompanying prospectus and in our most recent Annual Repor




