FIDUS INVESTMENT Corp

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

SCHEDULE 14A

(RULE 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

Dear Stockholder:

You are cordially invited to attend Fidus Investment Corporation’s 2026 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on Wednesday, June 10, 2026 at 8:30 a.m. Central Time, at 1603 Orrington Avenue, Suite 1005, Evanston, Illinois, 60201.

The Notice of Annual Meeting and proxy statement accompanying this letter provide an outline of the business to be conducted at the Annual Meeting. I will also report on the progress of the Company during the past year and answer stockholders’ questions.

It is important that your shares be represented at the Annual Meeting. If you are a stockholder of record and are unable to attend the Annual Meeting in person, I urge you to vote your shares by completing, dating and signing the enclosed proxy card and promptly returning it in the envelope provided or, alternatively, by calling the toll-free telephone number or using the Internet as described on the proxy card. If a broker or other nominee holds your shares in “street name,” your broker has enclosed a voting instruction form, which you should use to vote those shares if you are unable to attend the Annual Meeting in person. The voting instruction form indicates whether you have the option to vote those shares by telephone or by using the Internet. Your vote is important.

Sincerely yours,

Edward H. Ross

Chairman & Chief Executive Officer

FIDUS INVESTMENT CORPORATION

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held On Wednesday, June 10, 2026

To the Stockholders of Fidus Investment Corporation:

The 2026 Annual Meeting of Stockholders (the “Annual Meeting”) of Fidus Investment Corporation (the “Company”) will be held at 1603 Orrington Avenue, Suite 1005, Evanston, Illinois, 60201, on Wednesday, June 10, 2026 at 8:30 a.m. (Central Time) for the following purposes:

1. To elect two Class III directors to serve until the 2029 annual meeting of stockholders and their respective successor has been duly elected and qualified (Proposal No. 1);

2. To approve a proposal to authorize the Company, subject to the approval of the Company’s Board of Directors, to sell or otherwise issue shares of its common stock during the next year at a price below the Company’s then current net asset value per share, subject to certain conditions as set forth in this proxy statement (including that the cumulative number of shares sold pursuant to such authority does not exceed 25% of its then outstanding common stock immediately prior to each such sale) (Proposal No. 2); and

3. To transact such other business as may properly come before the Annual Meeting, or any adjournments or postponements thereof.

You have the right to receive notice of and to vote at the Annual Meeting if you were a stockholder of record at the close of business on March 19, 2026. Whether or not you expect to be present in person at the Annual Meeting, please vote by signing the enclosed proxy card and returning it promptly in the self-addressed envelope provided or, alternatively, by calling the toll-free telephone number or using the Internet as described on the proxy card. If a broker or other nominee holds your shares in “street name,” your broker has enclosed a voting instruction form, which you should use to vote those shares. The voting instruction form indicates whether you have the option to vote those shares by telephone or by using the Internet. In the event there are not sufficient votes for a quorum or to approve or ratify any of the foregoing proposals at the time of the Annual Meeting, the Annual Meeting may be adjourned in order to permit further solicitation of proxies by the Company.

By order of the Board of Directors,

Shelby E. Sherard

Chief Financial Officer, Chief Compliance Officer and Corporate Secretary

Evanston, Illinois

This is an important meeting. To ensure proper representation at the Annual Meeting, please indicate your vote as to the matters to be acted on at the Annual Meeting by following the instructions provided in the enclosed proxy card or voting instruction form. Even if you vote your shares prior to the Annual Meeting, you still may attend the Annual Meeting and vote your shares in person.

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FIDUS INVESTMENT CORPORATION