As filed with the Securities and Exchange Commission on August 20, 2018

Securities Act File No. 333-225447

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM N-2

REGISTRATION STATEMENT

UNDER

GLADSTONE INVESTMENT CORPORATION

(Exact Name of Registrant as Specified in Charter)

1521 Westbranch

Drive, Suite 100

McLean, Virginia 22102

(Address of Principal Executive Offices)

Registrant’s Telephone Number, Including Area Code: (703) 287-5800

David Gladstone

Chairman and Chief Executive Officer

Gladstone Investment Corporation

1521 Westbranch Drive, Suite 100

McLean, Virginia 22102

(Name and Address of Agent For Service)

Copies to:

Lori B. Morgan

Sehrish Siddiqui

Bass, Berry & Sims PLC

150 Third Avenue

Suite 2800

Nashville, Tennessee 37201

Tel: (615) 742-6200

Fax: (615) 742-6293

Approximate Date of Proposed Public Offering: From time to time after the effective date of the registration statement.

If any securities being registered on this form will be offered on a delayed or continuous basis in reliance on Rule 415 under the Securities Act of 1933, other than securities offered in connection with a dividend reinvestment plan, check the following box.  ☒

It is proposed that this filing will become effective (check appropriate box)

☐  when declared effective pursuant to Section 8(c)

TABLE OF CONTENTS

EXPLANATORY NOTE

This Post-Effective Amendment No. 1 to the Registration Statement on Form N-2 (File No. 333-225447) (the “Registration Statement”) of Gladstone Investment Corporation is being filed pursuant to Rule 462(d) under the Securities Act of 1933, as amended (the “Securities Act”), solely for the purpose of filing additional exhibits to such Registration Statement. Accordingly, this Post-Effective Amendment No. 1 consists only of a facing page, this explanatory note and Part C of the Registration Statement on Form N-2 setting forth the exhibits to the Registration Statement. This Post-Effective Amendment No. 1 does not modify any other part of the Registration Statement. Pursuant to Rule 462(d) under the Securities Act, this Post-Effective Amendment No. 1 shall become effective immediately upon filing with the Securities and Exchange Commission. The contents of the Registration Statement are hereby incorporated by reference.

Part C — OTHER INFORMATION

The following financial statements of Gladstone Investment Corporation (the “Company” or the “Registrant”) are included in the Registration Statement in “Part A: Information Required in a Prospectus:”

GLADSTONE INVESTMENT CORPORATION

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

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The information contained under the heading “Plan of Distribution” in the prospectus is incorporated herein by reference, and any information concerning any underwriters will be contained in the accompanying prospectus supplement, if any.

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All of the expenses set forth above shall be borne by the Registrant.

The following list sets forth each of the companies considered to be “controlled” by the Registrant as defined by the Investment Company Act of 1940, as of March 31, 2018:

We may also be deemed to be under “common control” with the following entities: Gladstone Capital Corporation, a Maryland corporation; Gladstone Commercial Corporation, a Maryland corporation; and Gladstone Land Corporation, a Maryland corporation; by virtue of the fact that they are advised by our Adviser, Gladstone Management Corporation, as well as Gladstone Lending Corporation, a Maryland corporation, and Gladstone Participation Fund, LLC, a Delaware limited liability company, because 100% of the voting securities of each are owned by our Adviser.

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The following table sets forth the approximate number of record holders of our stock at June 1, 2018.

Subject to the Investment Company Act of 1940 as amended (the “1940 Act”) or any valid rule, regulation or order of the Securities and Exchange Commission (the “SEC”) thereunder, our amended and restated certificate of incorporation and bylaws provide that we will indemnify any person who was or is a party or is threatened to be made a party to any threatened action, suit or proceeding whether civil, criminal, administrative or investigative, by reason of the fact that he is or was our director or officer, or is or was serving at our request as a director, officer, partner or trustee of another corporation, real estate investment trust, partnership, joint venture, trust, employee benefit plan or other enterprise to the maximum extent permitted by Section 145 of the Delaware General Corporation Law. The 1940 Act provides that a company may not indemnify any director or officer against liability to it or its security holders to which he or she might otherwise be subject by reason of his or her willful misfeasance, bad faith, gross negligence or reckless disregard of the duties involved in the conduct of his or her office unless a determination is made by final decision of a court, by vote of a majority of a quorum of directors who are disinterested, non-party directors or by independent legal counsel that the liability for which indemnification is sought did not arise out of the foregoing conduct. In addition to any indemnification to which our directors and officers are entitled pursuant to our certificate of incorporation and bylaws and the Delaware General Corporation Law, our certificate of incorporation and bylaws permit us to indemnify our other employees and agents to the fullest extent permitted by the Delaware General Corporation Law, whether such employees or agents are serving us or, at our request, any other entity.

In addition, the Advisory Agreement between us and our Adviser, as well as the administration agreement between us and our Administrator, each provide that, absent willful misfeasance, bad faith, or gross negligence in the performance of their respective duties or by reason of the reckless disregard of their respective duties and obligations, our Adviser and our Administrator, as applicable, and their respective officers, managers, partners, agents, employees, controlling persons, members, and any other person or entity affiliated with them are entitled to indemnification from us for any damages, liabilities, costs, and expenses (including reasonable attorneys’ fees and amounts reasonably paid in settlement) arising from the rendering of our Adviser’s services under the Advisory Agreement or otherwise as our investment adviser, or the rendering of our Administrator’s services under the administration agreement, or otherwise as an administrator for us, as applicable.

Any underwriting agreement, entered into from time to time by the Registrant, may require the Registrant to indemnify the underwriters named therein and their directors, officers, employees or agents against any actions, claims, damages or other liabilities that may arise in connection with the certain offering of securities pursuant thereto, including liabilities under the Securities Act.

Insofar as indemnification for liability arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than

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the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

A description of any other business, profession, vocation or employment of a substantial nature in which our Adviser, and each director or executive officer of our Adviser, is or has been during the past two fiscal years, engaged in for his or her own account or in the capacity of director, officer, employee, partner or trustee, is set forth in Part A of this Registration Statement in the section entitled “Management.” Additional information regarding our Adviser and its officers and directors is set forth in its Form ADV, as filed with the SEC, and is incorporated herein by reference.

All accounts, books or other documents required to be maintained by Section 31(a) of the 1940 Act and the rules thereunder are maintained at the offices of:

Not applicable.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant has duly caused this Post-Effective Amendment No. 1 to this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of McLean and the Commonwealth of Virginia, on the 20^th day of August, 2018.

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment No. 1 has been signed below by the following persons in the capacities on August 20, 2018:

Exhibit List