The information in this preliminary prospectus supplement is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective.  This preliminary prospectus supplement is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

[FORM OF PROSPECTUS SUPPLEMENT TO BE USED IN

CONJUNCTION WITH FUTURE DEBT SECURITIES OFFERINGS]

PROSPECTUS SUPPLEMENT

(to Prospectus dated                 , 2011)

$

GOLUB CAPITAL BDC, INC.

% Senior [Subordinated] [Secured] Notes due

We are an externally managed, closed-end, non-diversified management investment company that has elected to be regulated as a business development company under the Investment Company Act of 1940. Our investment objective is to provide our stockholders with current income and capital appreciation through debt and minority equity investments in middle-market companies.

GC Advisors LLC serves as our investment adviser. GC Service Company, LLC serves as our administrator. GC Advisors LLC and GC Service Company, LLC are affiliated with Golub Capital, a leading lender to middle-market companies that had over $            billion of capital under management as of            ,          .

We are offering $            in aggregate principal amount of     % senior [subordinated] [secured] notes due     , or the “Notes.”  The Notes will mature on      ,     .  We will pay interest on the Notes on       ,         ,             and          of each year, beginning on           ,       .   We may redeem the Notes in whole or in part at any time or from time to time on or after            ,      at the redemption prices set forth under “Specific Terms of the Notes and the Offering—Optional Redemption” in this prospectus supplement.  The Notes will be issued in minimum denominations of $     and integral multiples of $   in excess thereof.

The Notes will be our direct senior [subordinated] [secured/unsecured] obligations and rank pari passu with all outstanding and future [secured/unsecured] [unsubordinated/subordinated] indebtedness.

[We intend to list the Notes on               , and we expect trading in the Notes on                 to begin within    days of the original issue date.  The Notes are expected to trade “flat,” which means that purchasers will not pay, and sellers will not receive, any accrued and unpaid interest on the Notes that is not reflected in the trading price.  Currently, there is no public market for the Notes.]

Investing in our securities involves a high degree of risk. Before buying any securities, you should read the discussion of the material risks of investing in our securities, including the risk of leverage, in “Risk Factors” beginning on page S-10 of this prospectus supplement and on page 14 of the accompanying prospectus.

This prospectus contains important information you should know before investing in our Notes. Please read it before you invest and keep it for future reference. We file annual, quarterly and current reports, proxy statements and other information about us with the Securities and Exchange Commission, or the SEC. This information is available free of charge by contacting us at 150 South Wacker Drive, Suite 800, Chicago, Illinois 60606, Attention: Investor Relations, or by calling us collect at (312) 205-5050. The SEC also maintains a website at http://www.sec.gov that contains such information.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.  

	Per Note		Total
Public offering price		%	$
Sales load (underwriting discounts and commissions)		%	$
Proceeds to us (before expenses)		%	$

[In addition, the underwriters may purchase up to an additional $     aggregate principal amount of the Notes at the public offering price, less the sales load payable by us, to cover over-allotments, if any, within                 days from the date of this prospectus supplement. If the underwriters exercise this option in full, the total sales load paid by us will be $               , and total proceeds, before expenses, will be $               .

The underwriters are offering the Notes as set forth in “Underwriting.” Delivery of the Notes in book-entry form through The Depository Trust Company will be made on or about                    , 2011.

The date of this prospectus supplement is                    , 2011

 

ABOUT THIS PROSPECTUS SUPPLEMENT

You should rely only on the information contained in this prospectus supplement and the accompanying prospectus. We have not, and the underwriters have not, authorized any other person to provide you with different information. We are not, and the underwriters are not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted.  You should assume that the information appearing in this prospectus supplement and the accompanying prospectus is accurate only as of the date on the front cover of this prospectus supplement.  Our business, financial condition, results of operations, cash flows and prospects may have changed since that date.  We will update these documents to reflect material changes only as required by law.   We are offering to sell and seeking offers to buy, securities only in jurisdictions where offers are permitted.

This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering and also adds to and updates information contained in the accompanying prospectus. The second part is the accompanying prospectus, which gives more general information and disclosure. To the extent the information contained in this prospectus supplement differs from the information contained in the accompanying prospectus, the information in this prospectus supplement shall control. You should read this prospectus supplement and the accompanying prospectus together with the additional information described under the heading, “Available Information” before investing in our Notes.

 

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

	Page
PROSPECTUS SUPPLEMENT SUMMARY	S-1
SPECIFIC TERMS OF THE NOTES AND THE OFFERING	S-7
RISK FACTORS	S-10
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	S-12
USE OF PROCEEDS	S-14
RATIO OF EARNINGS TO FIXED CHARGES	S-14
CAPITALIZATION	S-15
SELECTED CONSOLIDATED FINANCIAL DATA	S-16
MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION, RESULTS OF OPERATIONS AND CASH FLOWS	S-18
UNDERWRITING	S-19
UNITED STATES FEDERAL INCOME TAX CONSEQUENCES	S-23
LEGAL MATTERS	S-24
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM	S-24
AVAILABLE INFORMATION	S-24

PROSPECTUS

	Page
[Insert table of contents from base prospectus.]

PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights some of the information in this prospectus supplement and the accompanying prospectus. It is not complete and may not contain all of the information that you may want to consider. You should read the more detailed information set forth under “Risk Factors” and the other information included in this prospectus supplement and the accompanying prospectus carefully.

Except as otherwise indicated, the terms:

· “we,” “us,” “our” and “Golub Capital BDC” refer to Golub Capital BDC, Inc., a Delaware corporation, and its consolidated subsidiaries, including the Securitization Issuer and Holdings, and, for the periods prior to consummation of the BDC Conversion (as defined below), Golub Capital BDC LLC, a Delaware limited liability company, and its consolidated subsidiaries;

· “Holdings” refers to Golub Capital BDC 2010-1 Holdings LLC, our direct subsidiary, and “Securitization Issuer” refers to Golub Capital BDC 2010-1 LLC, our indirect subsidiary;

· “Controlling Class” refers to the most senior class of notes of the Securitization Issuer then outstanding;

· “Debt Securitization” refers to the $300 million term debt securitization that we completed on July 16, 2010;

· “GC Advisors” refers to GC Advisors LLC, our investment adviser;

· “GC Service” refers to GC Service Company, LLC, an affiliate of GC Advisors and our administrator; and

· “Golub Capital” refers, collectively, to the activities and operations of Golub Capital Incorporated and Golub Capital Management LLC, which entities employ all of Golub Capital’s investment professionals, as well as GC Advisors, GC Service, associated investment funds and their respective affiliates.

On April 13, 2010, we converted from a limited liability company into a corporation. In this conversion, Golub Capital BDC, Inc. succeeded to the business of Golub Capital BDC LLC and its consolidated subsidiary, and the members of Golub Capital BDC LLC became stockholders of Golub Capital BDC, Inc. In this prospectus, we refer to such transactions as the “BDC Conversion.” Prior to the BDC Conversion, Golub Capital BDC LLC held all of the outstanding limited liability company interests in our predecessor, Golub Capital Master Funding LLC, or GCMF.

Golub Capital BDC

We are an externally managed, closed-end, non-diversified management investment company that has elected to be regulated as a business development company under the Investment Company Act of 1940, as amended, or the 1940 Act. In addition, for tax purposes, we have elected to be treated as a regulated investment company, or RIC, under Subchapter M of the Internal Revenue Code of 1986, as amended, or the Code. We were formed in November 2009 to continue and expand the business of our predecessor, GCMF, which commenced operations in July 2007, to make investments in senior secured, unitranche (a loan that combines characteristics of traditional first lien senior secured loans and second lien or subordinated loans), mezzanine (a loan that ranks senior only to a borrower’s equity securities and ranks junior to all of such borrower’s other indebtedness in priority of payment) and second lien loans of middle-market companies that are, in most cases, sponsored by private equity firms. In this prospectus, the term “middle-market” generally refers to companies having earnings before interest, taxes, depreciation and amortization, or EBITDA, of between $5 million and $40 million annually.

S-1

Our investment objective is to maximize the total return to our stockholders in the form of current income and capital appreciation through debt and minority equity investments. We intend to achieve our investment objective by (1) accessing the established loan origination channels developed by Golub Capital, a leading lender to middle-market companies with over $     billion of capital under management as of        ,      , (2) selecting investments within our core middle-market company focus, (3) partnering with experienced private equity firms, or sponsors, in many cases with whom we have invested alongside in the past, (4) implementing the disciplined underwriting standards of Golub Capital and (5) drawing upon the aggregate experience and resources of Golub Capital.

We seek to create a diverse portfolio that includes senior secured, unitranche, mezzanine and second lien loans and warrants and minority equity securities by primarily investing approximately $5 million to $25 million of capital, on average, in the securities of U.S. middle-market companies. We may also selectively invest more than $25 million in some of our portfolio companies and generally expect that the size of our individual investments will vary proportionately with the size of our capital base.

As discussed in the “ — Market Opportunity” section below, we believe senior secured, unitranche, mezzanine and second lien loans represent particularly attractive investments when compared to similar loans originated in the 2006 – 2008 period because we expect pricing to be more attractive and borrowing terms and deal structures to be more conservative.

Our Adviser

Our investment activities are managed by our investment adviser, GC Advisors. GC Advisors is responsible for sourcing potential investments, conducting research and due diligence on prospective investments and equity sponsors, analyzing investment opportunities, structuring our investments and monitoring our investments and portfolio companies on an ongoing basis. GC Advisors was organized in September 2008 and is a registered investment adviser under the Investment Advisers Act of 1940, as amended, or the Advisers Act. Under our amended and restated investment advisory agreement with GC Advisors, or the Investment Advisory Agreement, we pay GC Advisors a base management fee and an incentive fee for its services. See “Management Agreements — Management Fee” in the accompanying prospectus for a discussion of the base management fee and incentive fee, including the cumulative income incentive fee and the income and capital gains incentive fee, payable by us to GC Advisors. Unlike most closed-end funds whose fees are based on assets net of leverage, our base management fee is based on our average-adjusted gross assets (including leverage but adjusted to exclude cash and cash equivalents so that investors do not pay the base management fee on such assets) and, therefore, GC Advisors benefits when we incur debt or use leverage. Additionally, under the incentive fee structure, GC Advisors benefits when capital gains are recognized and, because it determines when a holding is sold, GC Advisors controls the timing of the recognition of capital gains. Our board of directors is charged with protecting our interests by monitoring how GC Advisors addresses these and other conflicts of interest associated with its management services and compensation. While not expected to review or approve each borrowing, our independent directors periodically review GC Advisors’ services and fees as well as its portfolio management decisions and portfolio performance. In connection with these reviews, our independent directors consider whether our fees and expenses (including those related to leverage) remain appropriate. See “Management Agreements — Board Approval of the Investment Advisory Agreement” in the accompanying prospectus.

GC Advisors is an affiliate of Golub Capital and has entered into a staffing agreement, or the Staffing Agreement, with two Golub Capital affiliates, Golub Capital Incorporated and Golub Capital Management LLC. Under the Staffing Agreement, these companies make experienced investment professionals available to GC Advisors and provide access to the senior investment personnel of Golub Capital and its affiliates. The Staffing Agreement provides GC Advisors with access to investment opportunities, which we refer to in the aggregate as deal flow, generated by Golub Capital and its affiliates in the ordinary course of their businesses and commits the members of GC Advisors’ investment committee to serve in that capacity. As our investment adviser, GC Advisors is obligated to allocate investment opportunities among us and its other clients fairly and equitably over time in accordance with its allocation policy. See “Related Party Transactions and Certain Relationships” in the accompanying prospectus.  However, there can be no assurance that such opportunities will be allocated to us fairly or equitably in the short-term or over time. GC Advisors seeks to capitalize on the significant deal origination, credit underwriting, due diligence, investment structuring, execution, portfolio management and monitoring experience of Golub Capital’s investment professionals.

S-2

 

An affiliate of GC Advisors, GC Service, provides the administrative services necessary for us to operate. See “Management Agreements — Administration Agreement” in the accompanying prospectus for a discussion of the fees and expenses we are required to reimburse to GC Service.

About Golub Capital

Golub Capital, founded in 1994, is a leading lender to middle-market companies, with a long track record of investing in unitranche and junior capital financings, which is our long-term investment focus. Golub Capital invested more than $     billion in unitranche and mezzanine transactions across a variety of market environments and industries between 2001 and              ,        . From 2005 through 2010, Golub Capital invested in more than 250 middle-market companies and, as of                 ,    , it held debt investments in more than            middle-market companies.

Golub Capital’s middle-market lending group is managed by a four-member senior management team consisting of Lawrence E. Golub, David B. Golub, Gregory W. Cashman and Andrew H. Steuerman. As of         ,          , Golub Capital’s    investment professionals had an average of over    years of investment experience and were supported by     administrative and back office personnel that focus on operations, finance, legal and compliance, accounting and reporting, marketing, information technology and office management.

Market Opportunity

We intend to pursue an investment strategy focused on investing in senior secured, unitranche, mezzanine and second lien loans of, and warrants and minority equity securities in, U.S. middle-market companies.

Target Market.  We believe that small and middle-market companies in the United States with annual revenues between $10 million and $2.5 billion represent a significant growth segment of the U.S. economy and often require substantial capital investments to grow. Middle-market companies have generated a significant number of investment opportunities for investment funds managed or advised by Golub Capital and we believe that this market segment will continue to produce significant investment opportunities for us.

Specialized Lending Requirements.  We believe that several factors render many U.S. financial institutions ill-suited to lend to U.S. middle-market companies. For example, based on the experience of our management team, lending to U.S. middle-market companies (1) is generally more labor intensive than lending to larger companies due to the smaller size of each investment and the fragmented nature of information for such companies, (2) requires due diligence and underwriting practices consistent with the demands and economic limitations of the middle-market and (3) may also require more extensive ongoing monitoring by the lender.

Demand for Debt Capital.  We believe that private equity firms will continue to be active investors in middle-market companies. These private equity firms generally seek to leverage their investments by combining their capital with senior secured loans and/or mezzanine debt provided by other sources, and we believe that our capital is well positioned to partner with such equity investors. We expect such activity to be funded by the substantial amounts of private equity capital that have been raised in recent years.

Refinancing Requirements.  We believe the debt associated with a large number of middle-market leveraged mergers and acquisitions completed from 2005 to 2008 will start to come due in the near term and, accordingly, we believe that new financing opportunities will increase as many leveraged companies seek to refinance in the near term.

Deal Structures.  We believe that as a result of the credit crisis, many lenders are requiring less senior and total leverage and more comprehensive loan covenants than was customary in the years leading up to the credit crisis.

S-3

Competitive Strengths

Deep, Experienced Management Team.  We are managed by GC Advisors, which has access through the Staffing Agreement to the resources and expertise of Golub Capital’s       employees, led by our chairman, Lawrence E. Golub, and our chief executive officer, David B. Golub. As of            ,        , the      investment professionals of Golub Capital had an average of over      years of investment experience and were supported by       administrative and back office personnel that focus on operations, finance, legal and compliance, accounting and reporting, marketing, information technology and office management. Golub Capital seeks to hire and retain high-quality investment professionals and reward those personnel based on investor returns. In 2009, Buyouts Magazine named Golub Capital “Middle-Market Lender of the Year” for the second consecutive year and M&A Advisor named Golub Capital the “Mezzanine Financing Agent of the Year” in 2009. These awards do not constitute an endorsement by any such publication or organization of the securities being offered by this prospectus supplement.

Leading U.S. Debt Platform Provides Access to Proprietary Relationship-Based Deal Flow.  GC Advisors gives us access to the deal flow of Golub Capital, one of the leading middle-market lenders in the United States. Reuters Loan Pricing Corporation ranked Golub Capital as the leading senior lender for middle-market leveraged buyouts (total debt financing of under $100 million) for 2009, based both on deal volume and number of deals. Since its inception, Golub Capital has completed at least one debt financing with over 110 sponsors and closed multiple debt financings with over 40 sponsors. We believe that Golub Capital receives relationship-based “early looks” and “last looks” at many investment opportunities in the U.S. middle-market market, allowing it to be highly selective in the transactions it pursues.

Disciplined Investment and Underwriting Process.  GC Advisors utilizes the established investment process of Golub Capital for reviewing lending opportunities, structuring transactions and monitoring investments. Using its disciplined approach to lending, GC Advisors seeks to minimize credit losses through effective underwriting, comprehensive due diligence investigations, structuring and the implementation of restrictive debt covenants.

Regimented Credit Monitoring.  Following each investment, GC Advisors implements a regimented credit monitoring system. This careful approach, which involves ongoing review and analysis by teams of professionals, has enabled us to identify problems early and to assist borrowers before they face difficult liquidity constraints.

Concentrated Middle-Market Focus.  Because of our focus on the middle-market, we understand the following general characteristics of middle-market lending:

· middle-market companies are generally less leveraged than large companies and, we believe, offer more attractive investment returns in the form of upfront fees, prepayment penalties and higher interest rates;

· middle-market issuers are more likely to have simple capital structures;

· carefully structured covenant packages enable middle-market lenders to take early action to remediate poor financial performance; and

· middle-market lenders can undertake thorough due diligence investigations prior to investment.

Organizational Structure

[Insert simplified organizational chart based on corporate structure at time of offering.]

Recent Developments

[Insert description of recent developments at time of offering.]

Operating and Regulatory Structure

Our investment activities are managed by GC Advisors and supervised by our board of directors, a majority of whom are independent of us, GC Advisors and its affiliates.

 

S-4

 

As a business development company, we are required to comply with certain regulatory requirements. For example, while we are permitted to finance investments using leverage, which may include the issuance of shares of preferred stock, or notes and other borrowings, our ability to use leverage is limited in significant respects. See “Regulation” in the accompanying prospectus.  Any decision on our part to use leverage will depend upon our assessment of the attractiveness of available investment opportunities in relation to the costs and perceived risks of such leverage. GC Advisors makes recommendations to our board of directors with respect to leverage policies. Our board of directors determines our leverage policy, including approving in advance the occurrence of material indebtedness and the execution of material contracts, and directs GC Advisors to implement such policies. The use of leverage to finance investments creates certain risks and potential conflicts of interest. See “Risk Factors — Risks Relating to our Business and Structure — There are significant potential conflicts of interest that could affect our investment returns. — Our management and incentive fee structure may create incentives for GC Advisors that are not fully aligned with the interests of our stockholders,” “Risks Relating to our Business and Structure — Regulations governing our operation as a business development company affect our ability to, and the way in which we, raise additional capital. As a business development company, the necessity of raising additional capital exposes us to risks, including the typical risks associated with leverage” and “Risks Relating to our Business and Structure —  We intend to finance our investments with borrowed money, which will magnify the potential for gain or loss on amounts invested and may increase the risk of investing in us” in the accompanying prospectus.

Also, as a business development company, we are generally prohibited from acquiring assets other than “qualifying assets” unless, after giving effect to any acquisition, at least 70% of our total assets are qualifying assets. Qualifying assets generally include securities of “eligible portfolio companies,” cash, cash equivalents, U.S. government securities and high-quality debt investments maturing in one year or less from the time of investment. Under the rules of the 1940 Act, “eligible portfolio companies” include (1) private domestic operating companies, (2) public domestic operating companies whose securities are not listed on a national securities exchange (e.g., the New York Stock Exchange, NYSE Amex Equities and The NASDAQ Global Market) or registered under the Securities Exchange Act of 1934, as amended, or the Exchange Act, and (3) public domestic operating companies having a market capitalization of less than $250 million. Public domestic operating companies whose securities are quoted on the over-the-counter bulletin board and through Pink Sheets LLC are not listed on a national securities exchange and therefore are eligible portfolio companies. See “Regulation” in the accompanying prospectus supplement.

Conflicts of Interests

Subject to certain 1940 Act restrictions on co-investments with affiliates, GC Advisors offers us the right to participate in all investment opportunities that it determines are appropriate for us in view of our investment objective, positions, policies, strategies and restrictions as well as regulatory requirements and other relevant factors. Such offers are subject to the exception that, in accordance with GC Advisors’ code of ethics and allocation policies, we might not participate in each individual opportunity but will, on an overall basis, be entitled to participate equitably with other entities sponsored or managed by GC Advisors and its affiliates.

To the extent that we compete with entities sponsored or managed by GC Advisors or its affiliates for a particular investment opportunity, GC Advisors will allocate investment opportunities across the entities for which such opportunities are appropriate, consistent with (1) its internal conflict of interest and allocation policies, (2) the requirements of the Advisers Act and (3) certain restrictions under the 1940 Act regarding co-investments with affiliates. GC Advisors’ allocation policies are intended to ensure that, over time, we may generally share equitably in investment opportunities with other investment funds, accounts or other investment vehicles, together referred to as accounts, sponsored or managed by GC Advisors or its affiliates, particularly those involving a security with limited supply or involving differing classes of securities of the same issuer which may be suitable for us and such other accounts.

 

S-5

 

GC Advisors has historically sponsored or managed, and currently sponsors or manages, accounts with similar or overlapping investment strategies and has put in place a conflict-resolution policy that addresses the co-investment restrictions set forth under the 1940 Act. GC Advisors seeks to ensure the equitable allocation of investment opportunities when we are able to invest alongside other accounts sponsored or managed by GC Advisors and its affiliates. When we invest alongside such other accounts, such investments are made consistent with GC Advisors’ allocation policy. Under this allocation policy, GC Advisors will determine separately the amount of any proposed investment to be made by us and similar eligible accounts. We expect that these determinations will be made similarly for other accounts sponsored or managed by GC Advisors and its affiliates. If sufficient securities or loan amounts are available to satisfy our and each such account’s proposed investment, the opportunity will be allocated in accordance with GC Advisor’s pre-transaction determination. Where there is an insufficient amount of an investment opportunity to fully satisfy us and other accounts sponsored or managed by GC Advisors or its affiliates, the allocation policy further provides that allocations among us and other accounts will generally be made pro rata based on the amount that each such party would have invested if sufficient securities or loan amounts were available. In situations in which co-investment with other entities sponsored or managed by GC Advisors or its affiliates is not permitted or appropriate, such as when, in the absence of exemptive relief described below, we and such other entities would be making different investments in the same issuer, GC Advisors will need to decide whether we or such other entity or entities will proceed with the investment. GC Advisors will make these determinations based on its policies and procedures, which generally require that such opportunities be offered to eligible accounts on a basis that will be fair and equitable over time, including, for example, through random or rotational methods. We and GC Advisors have submitted an exemptive application to the SEC to permit greater flexibility to negotiate the terms of co-investments if our board of directors determines that it would be advantageous for us to co-invest with other accounts sponsored or managed by GC Advisors or its affiliates in a manner consistent with our investment objectives, positions, policies, strategies and restrictions as well as regulatory requirements and other pertinent factors. See “Related Party Transactions and Certain Relationships” in the accompanying prospectus.

GC Advisors and its affiliates have other clients with similar or competing investment objectives, including several private funds that are pursuing an investment strategy similar to ours, some of which are continuing to seek new capital commitments. In serving these clients, GC Advisors may have obligations to other clients or investors in those entities. Our investment objective may overlap with such affiliated accounts. GC Advisors’ allocation procedures are designed to allocate investment opportunities among the accounts sponsored or managed by GC Advisors and its affiliates in a manner consistent with its obligations under the Advisers Act. If two or more accounts with similar investment strategies are actively investing, GC Advisors will seek to allocate investment opportunities among eligible accounts in a manner that is fair and equitable over time and consistent with its allocation policy. See “Risk Factors — Risks Relating to our Business and Structure — Conflicts related to obligations GC Advisors’ investment committee, GC Advisors or its affiliates have to other clients.” Additionally, under our incentive fee structure, GC Advisors benefits when we recognize capital gains and, because GC Advisors determines when a holding is sold, GC Advisors controls the timing of the recognition of such capital gains. See “Risk Factors — Risks Relating to our Business and Structure — Our management and incentive fee structure may create incentives for GC Advisors that are not fully aligned with the interests of our stockholders” in the accompanying prospectus.  In addition, because the base management fee that we pay to GC Advisors is based on our average adjusted gross assets, including those assets acquired through the use of leverage, GC Advisors has a financial incentive to incur leverage.

Our principal executive offices are located at 150 South Wacker Drive, Suite 800, Chicago, Illinois 60606, and our telephone number is (312) 205-5050. Our corporate website is located at www.golubcapitalbdc.com. Information on our website is not incorporated into or a part of this prospectus.

Risk Factors

The value of our assets, as well as the market price of our securities, will fluctuate. Our investments may be risky, and you may lose all or part of your investment in us. See “Risk Factors” beginning on page          of the accompanying prospectus, and the other information included in the accompanying prospectus, for additional discussion of factors you should carefully consider before deciding to invest in our securities.

S-6

SPECIFIC TERMS OF THE NOTES AND THE OFFERING

This prospectus supplement sets forth certain terms of the Notes that we are offering pursuant to this prospectus supplement and supplements the accompanying prospectus that is attached to the back of this prospectus supplement. This section outlines the specific legal and financial terms of the Notes. You should read this section together with the more general description of the Notes in the accompanying prospectus under the heading "Description of Our Debt Securities" before investing in the Notes. Capitalized terms used in this prospectus supplement and not otherwise defined shall have the meanings ascribed to them in the accompanying prospectus or in the indenture governing the Notes.

Issuer	Golub Capital BDC, Inc.
Title of the securities	% Senior [Subordinated] [Secured] Notes due
Initial aggregate principal amount being offered	$
Overallotment option	The underwriters may also purchase from us up to an additional $       aggregate principal amount of Notes to cover overallotments, if any, within       days of the date of this prospectus supplement.
Initial public offering price	% of the aggregate principal amount
Principal payable at maturity	% of the aggregate principal amount; the principal amount of each Note will be payable on its stated maturity date at the office of the Paying Agent, Registrar and Transfer Agent for the Notes or at such other office in The City of New York as we may designate.
Type of Note	[Fixed/Floating] rate note
Interest rate	% per year
Day count basis	360-day year of twelve 30-day months
Original issue date
Stated maturity date
Date interest starts accruing
Interest payment dates	Each        ,         ,         and            , commencing          ,          . If an interest payment date falls on a non-business day, the applicable interest payment will be made on the next business day and no additional interest will accrue as a result of such delayed payment.
Interest periods	The initial interest period will be the period from and including          , to, but excluding, the initial interest payment date, and the subsequent interest periods will be the periods from and including an interest payment date to, but excluding, the next interest payment date or the stated maturity date, as the case may be.
Record dates for interest	Each         ,         ,         and            , commencing         ,
[Additional Amounts Payable	List any additional amounts payable in respect of any tax, assessment or governmental charge.]
[Conversion/Exchange	List any provisions for convertibility or exchangeability of the debt securities into or for any other securities.]
Specified currency	U.S. Dollars
Place of payment	New York City
Ranking of Notes	The Notes will be our direct [un]secured obligations and will rank:
	•   pari passu with our other outstanding and future senior [un]secured indebtedness, including [       ];
	•  senior to any of our future indebtedness that expressly provides it is subordinated to the Notes;

S-7

	•   [effectively subordinated to all of our existing and future secured indebtedness (including indebtedness that is initially unsecured to which we subsequently grant security), to the extent of the value of the assets securing such indebtedness, including [      ]]; and
	•   structurally subordinated to all existing and future indebtedness and other obligations of any of our subsidiaries, financing vehicles or similar facilities[, including       ].
[Collateral	Our obligations with respect to the Notes and the performance of all of our other obligations under the indenture governing the Notes will be secured equally and ratably with our obligations under any other pari passu debt by a [first/second] priority security interest over [describe assets over which security is being granted].]
Denominations	We will issue the Notes in denominations of $      and integral multiples of $       in excess thereof.
Business day	Each Monday, Tuesday, Wednesday, Thursday and Friday that is not a day on which banking institutions in New York City are authorized or required by law or executive order to close.
Optional redemption	The Notes may be redeemed in whole or in part at any time or from time to time at our option on or after         ,         , upon not less than          days nor more than       days written notice by mail prior to the date fixed for redemption thereof, at a redemption price of $      per Note plus accrued and unpaid interest payments otherwise payable for the then-current quarterly interest period accrued to but not including the date fixed for redemption.
	You may be prevented from exchanging or transferring the Notes when they are subject to redemption. In case any Notes are to be redeemed in part only, the redemption notice will provide that, upon surrender of such Note, you will receive, without a charge, a new Note or Notes of authorized denominations representing the principal amount of your remaining unredeemed Notes.
	Any exercise of our option to redeem the Notes will be done in compliance with the 1940 Act, to the extent applicable.
	If we redeem only some of the Notes, the Trustee will determine the method for selection of the particular Notes to be redeemed, in accordance with the 1940 Act, to the extent applicable. Unless we default in payment of the redemption price, on and after the date of redemption, interest will cease to accrue on the Notes called for redemption.
Sinking fund	The Notes will not be subject to any sinking fund.
Repayment at option of Holders	Holders will not have the option to have the Notes repaid prior to the stated maturity date.
Defeasance	The Notes are subject to defeasance by us.
Covenant defeasance	The Notes are subject to covenant defeasance by us.
Form of Notes	The Notes will be represented by global securities that will be deposited and registered in the name of The Depository Trust Company, or DTC, or its nominee. Except in limited circumstances, you will not receive certificates for the Notes. Beneficial interests in the Notes will be represented through book-entry accounts of financial institutions acting on behalf of beneficial owners as direct and indirect participants in DTC. Investors may elect to hold interests in the Notes through either DTC, if they are a participant, or indirectly through organizations which are participants in DTC.
Trustee, Paying Agent, Registrar and Transfer Agent	US. Bank National Association

S-8

Other covenants	In addition to the covenants described in the prospectus attached to this prospectus supplement, the following covenants shall apply to the Notes:
	•   We agree that for the period of time during which the Notes are outstanding, we will not violate Section 18(a)(1)(A) as modified by Section 61(a)(1) of the 1940 Act or any successor provisions.
	•   If, at any time, we are not subject to the reporting requirements of Sections 13 or 15(d) of the Exchange Act to file any periodic reports with the SEC, we agree to furnish to holders of the Notes and the Trustee, for the period of time during which the Notes are outstanding, our audited annual consolidated financial statements, within            days of our fiscal year end, and unaudited interim consolidated financial statements, within            days of our fiscal quarter end. All such financial statements will be prepared, in all material respects, in accordance with applicable United States generally accepted accounting principles.
[Listing	We intend to list the Notes on           within           days of the original issue date.]
Global Clearance and Settlement Procedures	Interests in the Notes will trade in DTC’s Same Day Funds Settlement System, and any permitted secondary market trading activity in such Notes will, therefore, be required by DTC to be settled in immediately available funds. None of the issuer, the Trustee or the paying agent will have any responsibility for the performance by DTC or its participants or indirect participants of their respective obligations under the rules and procedures governing their operations.

S-9

RISK FACTORS

Investing in our securities involves a number of significant risks. Before you invest in our securities, you should be aware of various risks, including those described below and those set forth in the accompanying prospectus. You should carefully consider these risk factors, together with all of the other information included in this prospectus supplement and the accompanying prospectus, before you decide whether to make an investment in our securities. The risks set out below are not the only risks we face. Additional risks and uncertainties not presently known to us or not presently deemed material by us may also impair our operations and performance. If any of the following events occur, our business, financial condition, results of operations and cash flows could be materially and adversely affected. In such case, our net asset value and the trading price of our common stock could decline, and you may lose all or part of your investment. The risk factors described below, together with those set forth in the accompanying prospectus, are the principal risk factors associated with an investment in us as well as those factors generally associated with an investment company with investment objectives, investment policies, capital structure or trading markets similar to ours.

[The Notes will be unsecured and therefore will be effectively subordinated to any secured indebtedness we may incur.

The Notes will not be secured by any of our assets or any of the assets of our subsidiaries. As a result, the Notes are effectively subordinated to any secured indebtedness we or our subsidiaries have outstanding as of the date of this prospectus supplement or that they may incur in the future (or any indebtedness that is initially unsecured to which we subsequently grant security) to the extent of the value of the assets securing such indebtedness. In any liquidation, dissolution, bankruptcy or other similar proceeding, the holders of any of our existing or future secured indebtedness and the secured indebtedness of our subsidiaries may assert rights against the assets pledged to secure that indebtedness in order to receive full payment of their indebtedness before the assets may be used to pay other creditors, including the holders of the Notes. As of [   ], we had $[  ] million in outstanding indebtedness that is senior to the Notes. Certain amounts of this indebtedness are secured by certain of our assets and the indebtedness thereunder is therefore effectively senior to the Notes to the extent of the value of such assets.]

The Notes will be subordinated structurally to the indebtedness and other liabilities of our subsidiaries.

The Notes are obligations exclusively of Golub Capital BDC and not of any of our subsidiaries. None of our subsidiaries is a guarantor of the Notes. Except to the extent we are a creditor with recognized claims against our subsidiaries, all claims of creditors, including trade creditors, and holders of preferred stock, if any, of our subsidiaries will have priority over our claims (and therefore the claims of our creditors, including holders of the Notes) with respect to the assets of such subsidiaries. Even if we were recognized as a creditor of one or more of our subsidiaries, our claims would still be effectively subordinated to any security interests in the assets of any such subsidiary and to any indebtedness or other liabilities of any such subsidiary senior to our claims. Consequently, the Notes will be subordinated structurally to all indebtedness and other liabilities, including trade payables, of any of our subsidiaries and any subsidiaries that we may in the future acquire or establish as financing vehicles or otherwise. All of the existing indebtedness of our subsidiaries would be structurally senior to the Notes. In addition, our subsidiaries may incur substantial additional indebtedness in the future, all of which would be structurally senior to the Notes.

The indenture governing the Notes will be issued will contain limited protection for holders of the Notes.

The indenture governing the Notes will be issued offers limited protection to holders of the Notes. The terms of the indenture and the Notes do not restrict our or any of our subsidiaries' ability to engage in, or otherwise be a party to, a variety of corporate transactions, circumstances or events that could have an adverse impact on your investment in the Notes. In particular, the terms of the indenture and the Notes will not place any restrictions on our or our subsidiaries' ability to:

S-10

• [issue securities or otherwise incur additional indebtedness or other obligations, including (1) any indebtedness or other obligations that would be equal in right of payment to the Notes, (2) any indebtedness or other obligations that would be secured and [therefore] rank [effectively] senior in right of payment to the Notes to the extent of the values of the assets securing such debt, (3) indebtedness of ours that is guaranteed by one or more of our subsidiaries and [which therefore] is structurally senior to the Notes and (4) securities, indebtedness or obligations issued or incurred by our subsidiaries that would be senior to our equity interests in our subsidiaries and therefore rank structurally senior to the Notes with respect to the assets of our subsidiaries, in each case other than an incurrence of indebtedness or other obligation that would cause a violation of Section 18(a)(1)(A) as modified by Section 61(a)(1) of the 1940 Act or any successor provisions;

• pay dividends on, or purchase or redeem or make any payments in respect of, capital stock or other securities ranking junior in right of payment to the Notes;

• sell assets (other than certain limited restrictions on our ability to consolidate, merge or sell all or substantially all of our assets);

• enter into transactions with affiliates;

• create liens (including liens on the shares of our subsidiaries) or enter into sale and leaseback transactions;

• make investments; or

• create restrictions on the payment of dividends or other amounts to us from our subsidiaries.]

In addition, the terms of the indenture and the Notes do not protect holders of the Notes in the event that we experience changes (including significant adverse changes) in our financial condition, results of operations or credit ratings, as they do not require that we or our subsidiaries adhere to any financial tests or ratios or specified levels of net worth, revenues, income, cash flow or liquidity except as required by the 1940 Act.

Our ability to recapitalize, incur additional debt and take a number of other actions that are not limited by the terms of the Notes may have important consequences for you as a holder of the Notes, including making it more difficult for us to satisfy our obligations with respect to the Notes or negatively affecting the trading value of the Notes.

Certain of our current debt instruments include more protections for their holders than the indenture and the Notes. In addition, other debt we issue or incur in the future could contain more protections for its holders than the indenture and the Notes, including additional covenants and events of default. The issuance or incurrence of any such debt with incremental protections could affect the market for and trading levels and prices of the Notes.

An active trading market for the Notes may not develop, which could limit the market price of the Notes or your ability to sell them. [Because one or more rating agencies have assigned the Notes a non-investment grade rating, the Notes may be subject to greater price volatility than similar securities without such a rating.]

The Notes are a new issue of debt securities for which there currently is no trading market. [Although we expect the Notes to be listed on           ,] we cannot provide any assurances that an active trading market will develop for the Notes or that you will be able to sell your Notes. If the Notes are traded after their initial issuance, they may trade at a discount from their initial offering price depending on prevailing interest rates, the market for similar securities, our credit ratings, general economic conditions, our financial condition, performance and prospects and other factors. [Moreover, because one or more rating agencies have assigned the Notes a non-investment grade rating, the Notes may be subject to greater price volatility than securities of similar maturity without such a non-investment grade rating.] The underwriters have advised us that they intend to make a market in the Notes, but they are not obligated to do so. The underwriters may discontinue any market-making in the Notes at any time at their sole discretion. Accordingly, we cannot assure you that a liquid trading market will develop for the Notes, that you will be able to sell your Notes at a particular time or that the price you receive when you sell will be favorable. To the extent an active trading market does not develop, the liquidity and trading price for the Notes may be harmed. Accordingly, you may be required to bear the financial risk of an investment in the Notes for an indefinite period of time.

[Insert any additional relevant risk factors not included in base prospectus.]

S-11

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS 

Some of the statements in this prospectus supplement and the accompanying prospectus constitute forward-looking statements, which relate to future events or our future performance or financial condition. The forward-looking statements contained in this prospectus supplement and the accompanying prospectus involve risks and uncertainties, including statements as to:

· our future operating results;

· our business prospects and the prospects of our portfolio companies;

· the effect of investments that we expect to make;

· our contractual arrangements and relationships with third parties;

· actual and potential conflicts of interest with GC Advisors and other affiliates of Golub Capital;

· the dependence of our future success on the general economy and its effect on the industries in which we invest;

· the ability of our portfolio companies to achieve their objectives;

· the use of borrowed money to finance a portion of our investments;

· the adequacy of our financing sources and working capital;

· the timing of cash flows, if any, from the operations of our portfolio companies;

· the ability of GC Advisors to locate suitable investments for us and to monitor and administer our investments;

· the ability of GC Advisors or its affiliates to attract and retain highly talented professionals;

· our ability to qualify and maintain our qualification as a RIC and as a business development company;

· the impact on our business of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the rules and regulations issued thereunder; and

· the effect of changes to tax legislation and our tax position.

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.

We have based the forward-looking statements included in this prospectus supplement on information available to us on the date of this prospectus supplement, and we assume no obligation to update any such forward-looking statements. Actual results could differ materially from those implied or expressed in our forward-looking statements for any reason, including the factors set forth as “Risk Factors” and elsewhere in this prospectus supplement and accompanying prospectus, and future results could differ materially from historical performance. Although we 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 we may make directly to you or through reports that we have filed or in the future may file with the SEC, including annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

S-12

You should understand that, under Sections 27A(b)(2)(B) of the Securities Act and Section 21E(b)(2)(B) of the Exchange Act, the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995 do not apply to statements made in connection with any offering of securities pursuant to this prospectus supplement, the accompanying prospectus or in periodic reports we file under the Exchange Act.

S-13

USE OF PROCEEDS

We estimate that net proceeds we will receive from the sale of $               aggregate principal amount of Notes in this offering will be approximately $            million (or approximately $            million if the underwriters fully exercise their overallotment option), after deducting the underwriting discounts and commissions of $            million (or approximately $            million if the underwriters fully exercise their overallotment option) payable by us and estimated offering expenses of approximately $            payable by us.

We intend to use the net proceeds from the sale of Notes to [invest in portfolio companies in accordance with our investment objective and strategies and for general corporate purposes]. We expect that our new investments will consist primarily of senior secured, unitranche, mezzanine and second lien loans. We will also pay operating expenses, including management and administrative fees, and may pay other expenses such as due diligence expenses of potential new investments, from the net proceeds of any offering of our securities.

We anticipate that we will use substantially all of the net proceeds of an offering for the above purposes within approximately six months after the completion of any offering of our securities, depending on the availability of appropriate investment opportunities consistent with our investment objectives and market conditions. We cannot assure you that we will achieve our targeted investment pace.

Until such appropriate investment opportunities can be found, we will invest the net proceeds of any offering of our securities primarily in cash, cash equivalents, U.S. government securities and high-quality debt investments that mature in one year or less from the date of investment. These temporary investments may have lower yields than our other investments and, accordingly, may result in lower distributions, if any, during such period. See “Regulation — Temporary Investments” in the accompanying prospectus for additional information about temporary investments we may make while waiting to make longer-term investments in pursuit of our investment objective.

RATIO OF EARNINGS TO FIXED CHARGES

[Insert information required by Item 503(d) of Regulation S-K at time of offering.]

 

S-14

CAPITALIZATION

The following table sets forth:

· our actual capitalization as of                     , 20    ; and

· our pro forma capitalization to give effect to the sale of $                 aggregate principal amount of Notes in this offering based on the public offering price of $                     per Note, after deducting the underwriting discounts and commissions of $    million payable by us and estimated offering expenses of approximately $                     payable by us.

	As of                       , 20
	Actual	Pro Forma
	(dollars in thousands)
Assets:
Cash and cash equivalents	$	$
Investment at par value
Other assets
Total assets
Liabilities:
Debt
Other liabilities
Total liabilities
Net assets:
Common stock, par value $0.001 per share; 100,000,000 shares authorized,                     shares issued and outstanding                    shares issued and outstanding, pro forma
Paid in capital in excess of par
Capital distributions in excess of net investment income
Net unrealized appreciation on investments
Net realized gains (losses) on investments
Total stockholders’ equity
Net asset value per common share

S-15

SELECTED CONSOLIDATED FINANCIAL DATA

The following selected consolidated financial data for the fiscal years ended September 30, 2010, 2009, 2008 and for the fiscal period from July 27, 2007 (inception) through September 30, 2007, is derived from our consolidated financial statements that have been audited by McGladrey & Pullen, LLP, independent auditors. The Company’s consolidated financial statements for the       -month period ended            , 20   and 20    are unaudited. However, in our opinion, all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation have been made. Interim results may not be indicative of the results of operations for a full fiscal year. This financial data should be read in conjunction with our consolidated financial statements and the notes thereto included elsewhere in this Prospectus and with “Management’s Discussion and Analysis of Financial Condition, Results of Operations and Cash Flows” which follows.

	Golub Capital BDC(1)					GCMF
	Months Ended		Years ended
	, 20	, 20	September 30, 2010			September 30, 2009			September 30, 2008				For the Period July 27, 2007 (inception) through September 30, 2007
	(unaudited)		(in thousands, except per share data)
Statement of Operations Data:
Total investment income	$	$		33,150		$	33,338		$	20,686		$	1,868
Base management fee				3,328			2,849			1,726			134
Incentive fee				55			—			—			—
All other expenses				6,400			5,011			8,916			1,117
Net investment income				23,367			25,478			10,044			617
Net realized gain/(loss) on investments				(40	)		(3,972	)		(4,503	)		—
Net change in unrealized depreciation on investments				2,921			(1,489			(8,957	)		(558	)
Net increase/(decrease) in net assets resulting from operations				26,248			20,017			(3,416	)		59
Per share data:
Net asset value	$	$		14.71			N/A	(2)		N/A	(2)		N/A	(2)
Net investment income				N/A	(2)		N/A	(2)		N/A	(2)		N/A	(2)
Net realized gain on investments				N/A	(2)		N/A	(2)		N/A	(2)		N/A	(2)
Net change in unrealized depreciation on investments				N/A	(2)		N/A	(2)		N/A	(2)		N/A	(2)
Net increase in net assets resulting from operations				N/A	(2)		N/A	(2)		N/A	(2)		N/A	(2)
Per share distributions declared				0.55			N/A	(2)		N/A	(2)		N/A	(2)
Dollar amount of distributions declared				9,742			N/A	(2)		N/A	(2)		N/A	(2)
Other data:
Weighted average annualized yield on income producing assets at fair value(3)				8.4			8.1			9.3	%		6.4	%
Number of portfolio companies at period end				94			95			60			56

(1) Includes the financial information of GCMF for the period prior to our conversion to a Delaware corporation.

 

S-16

(2) Per share data are not provided as we did not have shares of common stock outstanding or an equivalent prior to the initial public offering on April 14, 2010.

(3) Weighted average yield on income producing investments is computed by dividing (1) annualized interest income (other than interest income resulting from amortization of fees and discounts) on accruing loans and debt securities by (2) total income producing investments at fair value.

	Golub Capital BDC				GCMF
	, 20	, 20	September 30, 2010		September 30, 2009		September 30, 2008		September 30, 2007
	(unaudited)								(unaudited)
			(in thousands)
Balance sheet data at period end:
Investments, at fair value	$	$	$	344,869	$	376,294	$	135,476	$	201,147
Cash and cash equivalents				92,990		30,614		4,252		4,237
Other assets				4,904		2,214		1,213		2,819
Total assets				442,763		409,122		140,941		208,203
Total liabilities				182,222		316,370		124,088		174,722
Total net assets				260,541		92,752		16,853		33,481

S-17

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION,

RESULTS OF OPERATIONS AND CASH FLOWS

The following discussion and analysis of our financial condition, results of operations and cash flows should be read in conjunction with “Selected Financial and Other Information” and the financial statements and the related notes thereto of us and our predecessor, GCMF, appearing elsewhere in this prospectus supplement and accompanying prospectus. On April 13, 2010, Golub Capital BDC LLC converted from a Delaware limited liability company into a Delaware corporation and elected to be regulated as a business development company under the 1940 Act. In this conversion, which we refer to as the BDC Conversion, Golub Capital BDC, Inc. assumed the business activities of Golub Capital BDC LLC and became the sole surviving entity. As a result of the conversion, GCMF became a wholly owned subsidiary of Golub Capital BDC, Inc. At the time of the BDC Conversion, all limited liability company interests were exchanged for 8,984,863 shares of common stock in Golub Capital BDC, Inc. Immediately prior to the BDC Conversion, the limited liability company interests were owned by investment vehicles managed by Golub Capital. For periods prior to April 13, 2010, the consolidated financial statements and related footnotes reflect the performance of Golub Capital BDC LLC and its predecessor, GCMF. The information in this section contains forward-looking statements that involve risks and uncertainties. Please see “Risk Factors” and “Special Note Regarding Forward-Looking Statements” for a discussion of the uncertainties, risks and assumptions associated with these statements.

[Insert Management’s Discussion and Analysis of Financial Condition, Results of Operations and Cash Flows from most recently filed Quarterly Report on Form 10-Q prior to offering.]

S-18

UNDERWRITING

We are offering the Notes described in this prospectus supplement and the accompanying prospectus through a number of underwriters.                    and                  are acting as representatives of the underwriters. We have entered into an underwriting agreement with the underwriters. Subject to the terms and conditions of the underwriting agreement, we have agreed to sell to the underwriters, and each underwriter has severally agreed to purchase the aggregate principal amount of Notes listed next to its name in the following table:

Underwriter	Principal Amount
Total

The underwriters are committed to purchase all of the Notes offered by us if they purchase any Notes. The underwriting agreement also provides that if an underwriter defaults, the purchase commitments of non-defaulting underwriters may also be increased or this offering may be terminated.

[Over-Allotment Option

The underwriters have an option to buy up to an additional $          aggregate principal amount of the Notes from us to cover sales of Notes by the underwriters which exceed the amount of Notes specified in the table above. The underwriters have 30 days from the date of this prospectus supplement to exercise this overallotment option. If any Notes are purchased with this overallotment option, the underwriters will purchase Notes in approximately the same proportion as shown in the table above. If any additional Notes are purchased, the underwriters will offer the additional Notes on the same terms as those on which the shares are being offered.]

The underwriters propose to offer the Notes directly to the public at the public offering price set forth on the cover page of this prospectus supplement and to certain dealers at that price less a concession not in excess of $     per Note. Any such dealers may resell Notes to certain other brokers or dealers at a discount of up to $     per Note from the public offering price. After the public offering of the Notes, the offering price and other selling terms may be changed by the underwriters. Sales of Notes made outside of the United States may be made by affiliates of the underwriters. The representatives have advised us that the underwriters do not intend to confirm discretionary sales in excess of     % of the Notes offered in this offering.

Commissions and Discounts

The underwriting fee is equal to    % of the public offering price per Note. The underwriting fee is $   per Note. The following table shows the per Note and total underwriting discounts and commissions to be paid to the underwriters assuming both no exercise and full exercise of the underwriters’ option to purchase additional Notes.

S-19

	Per Note		Total
			Without Over-Allotment	With Over-Allotment
Public offering price		%	$	$
Sales load (underwriting discounts and commissions)		%	$	$
Proceeds before expenses		%	$	$

We estimate that the total expenses of this offering, including registration, filing and listing fees, printing fees and legal and accounting expenses, but excluding the underwriting discounts and commissions, will be approximately $           , or approximately $        per Note excluding the over-allotment and approximately $      per Note including the over-allotment.

[Lock-Up Agreements

During the period from the date of this prospectus supplement continuing through the date     days after the date of this prospectus, we, GC Advisors, GC Service, our officers and directors and Golub Capital and certain of its affiliates have agreed with the representatives of the underwriters, subject to certain exceptions, not to:

(1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend or otherwise transfer or dispose of any shares of our common stock or any securities convertible into or exercisable or exchangeable for common stock, whether now owned or hereafter acquired, or

(2) enter into any swap or other agreement, arrangement or transaction that transfers to another, in whole or in part, directly or indirectly, any of the economic consequences of ownership of any common stock or any securities convertible into or exercisable or exchangeable for any common stock.

Moreover, if (1) during the last 17 days of such    -day restricted period, we issue an earnings release or material news or a material event relating to us occurs or (2) prior to the expiration of such   -day restricted period, we announce that we will release earnings results or become aware that material news or a material event will occur during the 16-day period beginning on the last day of such    -day restricted period, the restrictions described above shall continue to apply until the expiration of the 18-day period beginning on the date of issuance of the earnings release or the occurrence of the material news or material event, as the case may be, unless the representatives of the underwriters waive, in writing, such extension.]

Price Stabilizations and Short Positions

In connection with this offering,               and              , on behalf of the underwriters, may purchase and sell Notes in the open market. These transactions may include short sales, syndicate covering transactions and stabilizing transactions. Short sales involve sales by the underwriters of securities in excess of the number of securities required to be purchased by the underwriters in the offering, which creates a syndicate short position. “Covered” short sales are sales of securities made in an amount up to the number of securities represented by the underwriters’ over-allotment option. Transactions to close out the covered syndicate short involve either purchases of such securities in the open market after the distribution has been completed or the exercise of the over-allotment option. In determining the source of securities to close out the covered syndicate short position, the underwriters may consider the price of securities available for purchase in the open market as compared to the price at which they may purchase securities through the over-allotment option. The underwriters may also make “naked” short sales, or sales in excess of the over-allotment option. The underwriters must close out any naked short position by purchasing securities in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the securities in the open market after pricing that could adversely affect investors who purchase in this offering. Stabilizing transactions consist of bids for or purchases of securities in the open market while this offering is in progress for the purpose of fixing or maintaining the price of the securities.

 

S-20

The underwriters also may impose a penalty bid. Penalty bids permit the underwriters to reclaim a selling concession from an underwriter or syndicate member when the underwriters repurchase securities originally sold by that underwriter or syndicate member in order to cover syndicate short positions or make stabilizing purchases.

Any of these activities may have the effect of raising or maintaining the market price of the securities or preventing or retarding a decline in the market price of the securities. As a result, the price of the securities may be higher than the price that might otherwise exist in the open market. The underwriters may conduct these transactions on                   or otherwise. Neither we nor any of the underwriters makes any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our securities. In addition, neither we nor any of the underwriters makes any representation that the underwriters will engage in these transactions. If the underwriters commence any of these transactions, they may discontinue them at any time.

In connection with this offering, the underwriters may engage in passive market making transactions in our securities on                            in accordance with Rule 103 of Regulation M under the Exchange Act during a period before the commencement of offers or sales of securities and extending through the completion of distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. However, if all independent bids are lowered below the passive market maker’s bid, that bid must then be lowered when specified purchase limits are exceeded.

Additional Underwriter Compensation

Certain of the underwriters and their respective affiliates have from time to time performed and may in the future perform various commercial banking, financial advisory and investment banking services for us and our affiliates for which they have received or will receive customary compensation.  [Describe any specific transactions and compensation related thereto required to be disclosed by applicable law or regulation.]

Sales Outside the United States

No action has been taken in any jurisdiction (except in the United States) that would permit a public offering of the Notes, or the possession, circulation or distribution of this prospectus supplement or accompanying prospectus or any other material relating to us or the Notes in any jurisdiction where action for that purpose is required. Accordingly, our warrants may not be offered or sold, directly or indirectly, and none of this prospectus supplement, the accompanying prospectus or any other offering material or advertisements in connection with our warrants may be distributed or published, in or from any country or jurisdiction except in compliance with any applicable rules and regulations of any such country or jurisdiction.

Each of the underwriters may arrange to sell our Notes offered hereby in certain jurisdictions outside the United States, either directly or through affiliates, where it is permitted to do so.

[Insert applicable legends for jurisdictions in which offers and sales may be made.]

Electronic Delivery

The underwriters may make this prospectus supplement and accompanying prospectus available in an electronic format. The prospectus supplement and accompanying prospectus in electronic format may be made available on a website maintained by any of the underwriters, and the underwriters may distribute such documents electronically. The underwriters may agree with us to allocate a limited number of securities for sale to their online brokerage customers. Any such allocation for online distributions will be made by the underwriters on the same basis as other allocations.

We estimate that our share of the total expenses of this offering, excluding underwriting discounts, will be approximately $           .

S-21

We and GC Advisors have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act.

The addresses of the underwriters are:             .

S-22

UNITED STATES FEDERAL INCOME TAX CONSEQUENCES

[Insert disclosure regarding federal income tax consequences of an investment in the Notes.]

S-23

LEGAL MATTERS

Certain legal matters regarding the securities offered by this prospectus supplement will be passed upon for us by Dechert LLP, Washington, D.C. Dechert LLP has from time to time represented GC Advisors and the underwriters on unrelated matters.  Certain legal matters in connection with the securities offered hereby will be passed upon for the underwriters by                 ,                 ,                 .

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The consolidated financial statements of Golub Capital BDC, Inc. and Subsidiaries (the Company) (formerly known as Golub Capital BDC LLC and Golub Capital Master Funding LLC) as of September 30, 2010 and 2009 and for the three years ended September 30, 2010 appearing in this Prospectus and the Registration Statement have been audited by McGladrey & Pullen, LLP, an independent registered public accounting firm, as stated in their report appearing elsewhere herein, which report expresses an unqualified opinion and includes an explanatory paragraph relating to the Company’s investments whose fair values have been estimated by management, and are included in reliance upon such report and upon the authority of such firm as experts in accounting and auditing. 

AVAILABLE INFORMATION

We have filed with the SEC a registration statement on Form N-2, together with all amendments and related exhibits, under the Securities Act, with respect to our Notes offered by this prospectus supplement and the accompanying prospectus. The registration statement contains additional information about us and our Notes being offered by this prospectus supplement and the accompanying prospectus.

We file with or submit to the SEC annual, quarterly and current reports, proxy statements and other information meeting the informational requirements of the Exchange Act. You may inspect and copy these reports, proxy statements and other information, as well as the registration statement and related exhibits and schedules, at the SEC’s Public Reference Room at 100 F Street, NE, Washington, D.C. 20549-0102. You may obtain information on the operation of the Public Reference Room by calling the SEC at (202) 551-8090. We maintain a website at www.golubcapitalbdc.com and make all of our annual, quarterly and current reports, proxy statements and other publicly filed information available, free of charge, on or through our website. Information contained on our website is not incorporated into this prospectus, and you should not consider information on our website to be part of this prospectus. You may also obtain such information by contacting us in writing at 150 South Wacker Drive, Suite 800, Chicago, IL 60606, Attention: Investor Relations. The SEC maintains a website that contains reports, proxy and information statements and other information we file with the SEC at www.sec.gov. Copies of these reports, proxy and information statements and other information may also be obtained, after paying a duplicating fee, by electronic request at the following e-mail address: publicinfo@sec.gov, or by writing the SEC’s Public Reference Section, 100 F Street, N.E., Washington, D.C. 20549-0102.

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