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Filed Pursuant to Rule 497
Registration Statement No. 333-141828

PROSPECTUS SUPPLEMENT TO PROSPECTUS DATED MAY 16, 2007

12,000,000 Shares

Common Stock

This prospectus supplement supplements the prospectus dated May 16, 2007, relating to our offer, from time to time, of up to 12,000,000 shares of our common stock in one or more offerings, by providing certain information regarding our second quarter 2007 financial results. As of the date of this prospectus supplement, we have issued 9,200,000 shares of the common stock for total proceeds to us of approximately $117,990,000.

Please read this prospectus supplement, and the accompanying prospectus, before investing, and keep it for future reference. The prospectus supplement and the accompanying prospectus contain important information about us that a prospective investor should know before investing in our common stock. We file annual, quarterly and current reports, proxy statements and other information about us with the Securities and Exchange Commission. This information is available free of charge by contacting us at 400 Hamilton Avenue, Suite 310, Palo Alto, California 94301, or by telephone by calling collect at (650) 289-3060 or on our website at www.herculestech.com. The information on our website is not incorporated by reference into this prospectus or the accompanying prospectus. The SEC also maintains a website at www.sec.gov that contains such information.

An investment in our common stock involves risks, including the risk of a total loss of investment. In addition, the companies in which we invest are subject to special risks. See “ Risk Factors” beginning on page 12 of the accompanying prospectus to read about risks that you should consider before investing in our common stock, including the risk of leverage.

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

The date of this prospectus supplement is September 14, 2007.

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You should rely only on the information contained in this document or to which we have referred you. We have not authorized anyone to provide you with information that is different. This document may only be used where it is legal to sell these securities. The information in this document may only be accurate on the date of this document.

This document is in two parts. The first part is this prospectus supplement, which updates certain information in the accompanying prospectus by providing information regarding our second quarter 2007 Financial results. The second part is the accompanying prospectus, which gives additional information. 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.

Unless the context requires otherwise, in this prospectus supplement the terms “we,” “us,” and/or “the Company” refer to Hercules Technology Growth Capital, Inc. and its subsidiaries.

This prospectus supplement is part of a registration statement that we have filed with the Securities and Exchange Commission using the “shelf” registration process. Under the shelf registration process, which constitutes a delayed offering in reliance on Rule 415 under the Securities Act of 1933, as amended, we may offer, from time to time, up to 12,000,000 shares of common stock on terms to be determined at the time of the offering. The common stock may be offered at prices and on terms described in one or more supplements to the prospectus. The prospectus provides you with a general description of the common stock that we may offer. Each time we use the prospectus to offer common stock, we will provide a prospectus supplement that will contain specific information about the terms of that offering. Please carefully read the prospectus and any such supplements together with the additional information described under “Where You Can Find Additional Information” in the “Prospectus Summary” and “Risk Factors” sections before you make an investment decision.

A prospectus supplement may also add, update or change information contained in the prospectus.

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INTERIM MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following analysis of the financial condition and results of operations of the Company should be read in conjunction with the Company’s Consolidated Financial Statements and the Notes thereto included herein and in the Company’s annual report on Form 10-K for the year ended December 31, 2006.

Forward-Looking Statements

The information set forth in this report includes “forward-looking statements.” Such statements may include, but are not limited to: projections of revenues, income or loss, capital expenditures, plans for product development and cooperative arrangements, future operations, financing needs, or plans of Hercules, as well as assumptions relating to the foregoing. The terms “may,” “will,” “should,” “expects,” “plans,” “anticipates,” “could,” “intends,” “target,” “projects,” “contemplates,” “believes,” “estimates,” “predicts,” “potential,” or “continue,” or the negatives of these terms, or other similar expressions generally identify forward-looking statements.

The forward-looking statements made in this Form 10-Q speak only to events as of the date on which the statements are made. You should not place undue reliance on such forward-looking statements, as substantial risks and uncertainties could cause actual results to differ materially from those projected in or implied by these forward-looking statements due to a number of risks and uncertainties affecting its business. The forward-looking statements contained in this Form 10-Q are made as of the date hereof, and Hercules assumes no obligation to update the forward-looking statements for subsequent events.

Overview

We are a specialty finance company that provides debt and equity growth capital to technology-related companies at all stages of development. We primarily finance privately-held companies backed by leading venture capital and private equity firms and also may finance certain publicly-traded companies. We source our investments through our principal office located in Silicon Valley, as well as our additional offices in the Boston, Boulder, Chicago, Costa Mesa and Columbus areas. Our goal is to be the leading structured mezzanine capital provider of choice for venture capital and private equity backed technology-related and life science companies requiring sophisticated and customized financing solutions. Our strategy is to evaluate and invest in a broad range of companies active in the technology and life science industries and to offer a full suite of growth capital products up and down the capital structure. We invest primarily in structured mezzanine debt and, to a lesser extent, in senior debt and equity investments. We use the term “structured mezzanine debt investment” to refer to any debt investment, such as a senior or subordinated secured loan, that is coupled with an equity component, including warrants, options or rights to purchase common or preferred stock. Our structured mezzanine debt investments will typically be secured by some or all of the assets of the portfolio company.

Our investment objective is to maximize our portfolio’s total return by generating current income from our debt investments and capital appreciation from our equity-related investments. We are an internally managed, non-diversified closed-end investment company that has elected to be regulated as a business development company under the 1940 Act. As a business development company, we are required to comply with certain regulatory requirements. For instance, we generally have to invest at least 70% of our total assets in “qualifying assets,” including securities of private U.S. companies, cash, cash equivalents, U.S. government securities and high-quality debt investments that mature in one year of less.

We may engage in the asset management business by providing investment advisory services to externally managed funds that may be formed in the future. We may, from time to time, serve as the investment manager of such funds and may receive management and other fees for such services. Such funds may have overlapping investment objectives and may invest in asset classes similar to those targeted by us.

Portfolio and Investment Activity

The total value of our investment portfolio was $416.7 million at June 30, 2007 as compared to $283.2 million at December 31, 2006. During the three and six-month periods ended June 30, 2007, we made debt commitments to 15 and 29 portfolio companies totaling $143.1 million and $249.6, respectively. We funded $99.4 million to 23 companies and $177.8 million to 39 companies during the three and six-month periods ended June 30, 2007, respectively. During the three and six-month periods ended June 30, 2007, we also received normal principal repayments of approximately $16.7 million and $27.8 million, and early repayments and recoveries of $11.7 million and $13.5 million from five and seven companies, respectively, We also received pay downs of $9.1 million on working capital lines of credit for the six month period ended June 30, 2007. We did not receive any working capital paydowns during the three month period ended June 30, 2007. We also made equity investments in two and six portfolio companies totaling $1.0 million and $2.8 million during the three and six-month periods ended June 30, 2007, respectively, and sold one equity investment with a fair value of $500,000 during the six month period

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ended June 30, 2007. At June 30, 2007, our equity investments have a fair value of approximately $11.8 million. At June 30, 2007, we had unfunded contractual commitments of $111.1 million to 31 portfolio companies. In addition, as of June 30, 2007, we executed non-binding term sheets with six prospective portfolio companies, representing approximately $47.9 million. These proposed investments are subject to completion of our due diligence and final approval process, as well as the negotiation of definitive documentation with the prospective portfolio companies. Not all non-binding term sheets are expected to close and do not necessarily represent future cash requirements.

Total portfolio investment activity (exclusive of unearned income) as of and for the period ended June 30, 2007 was as follows:

The following table shows the fair value of our portfolio of investments by asset class as of June 30, 2007 and December 31, 2006 (excluding unearned income):

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A Summary of the company’s investment portfolio at value by geographic location is as follows.

The following table shows the fair value of our portfolio by industry sector at June 30, 2007 and December 31, 2006 (excluding unearned income):

We use an investment grading system, which grades each debt investment on a scale of 1 to 5, to characterize and monitor our expected level of risk on the debt investments in our portfolio with 1 being the highest quality. The following table shows the distribution of our outstanding debt investments on the 1 to 5 investment grading scale at fair value as of June 30, 2007 and December 31, 2006:

As of June 30, 2007, our investments had a weighted average investment grading of 2.16 as compared to 2.14 at December 31, 2006. Our policy is to reduce the grading on our portfolio companies as they approach the point in time when they will require additional equity capital. Additionally, we may downgrade our portfolio companies if they are not meeting our financing criteria and their respective business plans. Various companies in our portfolio will require additional funding in the near term or have not met their business plans and have therefore been downgraded until the funding is complete or their operations improve.

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The weighted average yield to maturity of our loan obligations was approximately 12.75%. Yields to maturity are computed using interest rates as of June 30, 2007 and include amortization of loan facility fees, commitment fees and market premiums or discounts over the expected life of the debt investments, weighted by their respective costs when averaged and are based on the assumption that all contractual loan commitments have been fully funded.

We generate revenue in the form of interest income, primarily from our investments in debt securities, and commitment and facility fees. Fees generated in connection with our debt investments are recognized over the life of the loan or, in some cases, recognized as earned. In addition, we generate revenue in the form of capital gains, if any, on warrants or other equity-related securities that we acquire from our portfolio companies. Our investments generally range from $1.0 million to $25.0 million, with an average initial principal balance of between $3.0 million and $7.0 million. Our debt investments have a term of between two and seven years and typically bear interest at a rate ranging from 8.0% to 14.0% (based on current interest rate conditions). In addition to the cash yields received on our loans, in some instances, our loans may also include any of the following: end-of-term payments, PIK interest exit fees, balloon payment fees, or prepayment fees, and diligence fees, which may be required to be included in income prior to receipt. In some cases, we collateralize our investments by obtaining security interests in our portfolio companies’ assets, which may include their intellectual property. In other cases, we may obtain a negative pledge covering a company’s intellectual property. See “Part II—Item 1A—Risk Factors.” At June 30, 2007, approximately 29 portfolio company loans were secured by a first priority security in all of the assets of the portfolio company and 38 portfolio company loans were prohibited from pledging or encumbering their intellectual property. Interest on debt securities is generally payable monthly, with amortization of principal typically occurring over the term of the security for emerging-growth and expansion-stage companies. In addition, certain loans may include an interest-only period ranging from three to twelve months. In limited instances in which we choose to defer amortization of the loan for a period of time from the date of the initial investment, the principal amount of the debt securities and any accrued but unpaid interest become due at the maturity date. Our mezzanine debt investments also generally have equity enhancement features, typically in the form of warrants or other equity-related securities designed to provide us with an opportunity for capital appreciation.

As of June 30, 2007, we have received warrants in connection with our debt investments in each portfolio company, and have realized gains on five warrant positions. We currently hold warrants in 70 portfolio companies, with a fair value of approximately $14.7 million included in the investment portfolio of $416.7 million. The fair value of the warrant portfolio has increased by 116.0% to $14.7 million as compared to the fair value of $6.8 million at June 30, 2006. These warrant holdings would allow us to invest approximately $41.5 million if such warrants are exercised.

Results of Operations

Comparison of the Three and Six-Month Periods Ended June 30, 2007 and 2006

Operating Income

Interest income totaled approximately $11.8 and $20.8 million for the three and six-month periods ended June 30, 2007, respectively, compared with $6.2 and $11.8 for the three and six-month periods ended June 30, 2006. Income from commitment and facility fees totaled approximately $1.5 and $2.1 million for the three and six-month periods ended June 30, 2007, respectively, as compared with approximately $612,000 and $1.5 million for the three and six-month periods ended June 30, 2006. The increases in investment income and income from commitment and facility fees for both periods presented are the result of higher average loan balances outstanding due to origination activity and yield from the related investments.

At June 30, 2007, we had approximately $4.9 million of deferred revenue related to commitment and facility fees, as compared to approximately $3.2 million as of June 30, 2006. We expect to generate additional interest income and loan fees as we continue to originate additional investments.

Operating Expenses

Operating expenses totaled approximately $6.0 million and $10.5 million during the three and six-month periods ended June 30, 2007, respectively, compared with $4.3 and $8.8 million during the three and six-month periods ended June 30, 2006, respectively. Operating expenses for the three and six-month periods ended June 30, 2007 included interest expense, loan fees and unused commitment fees under the Credit Facility of approximately $2.0 and $3.0 million, respectively, compared with $1.6 and $3.6 million for the three and six-month periods ended June 30, 2006, respectively. The increase in interest expense and loan fees was due to the higher average debt outstanding during the three months ended June 30, 2007 as compared to the same period in 2006. The expense was lower for the six month period of 2007 compared to 2006 due to a lower average debt balance and lower average interest rate. Employee compensation and benefits were approximately $2.0 and $4.0 million during the three and six-month periods ended June 30, 2007, respectively, compared with $1.1 and $2.3 million during the three and six-month periods ended June 30, 2006, respectively. The increase in compensation expense was directly related to increasing our number of employees from 19 employees at June 30, 2006 to 35 employees at June 30, 2007. General and administrative expenses increased to $1.7 and $3.0 million for the three and six-month periods ended June 30, 2007, up from $1.4 and $2.6 million during the three and six-month periods ended June 30, 2006, primarily due to increased legal expense related to workouts in two portfolio companies, professional service costs related to our status as a public company and the creation of our SBIC subsidiaries as well as increased business development expenses. In addition, we incurred approximately $293,000 and $547,000 of stock-based compensation expense during the three and six-month periods ended June 30, 2007, as compared to $130,000 and $253,000 in 2006, respectively.

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Net Investment Income Before Income Tax Expense and Investment Gains and Losses

Net investment income before provision for income tax expense for the three and six-month periods ended June 30, 2007 totaled $7.2 and $12.5 million, respectively, as compared with net investment income before provision for income tax expense of approximately $2.5 and $4.5 million for the three and six-month periods ended June 30, 2006. The changes are made up of the items described above under “Operating Income” and “Operating Expenses.”

Net Investment Gains/Losses

During the three month period ended June 30, 2007, we generated a net realized loss totaling approximately $272,000 due to the write-off of the warrant values in one portfolio company. This brings the total net realized gains to approximately $17,000 for the six month period ended June 30. 2007. During the three month period ended June 30, 2006, we generated a net realized gain totaling approximately $1.6 million due to the recovery of approximately $1.4 million on one portfolio company as well as the sale of equity and warrants of approximately $155,000 in one portfolio company. During the six month period ended June 30, 2006, we generated a net realized loss totaling approximately $141,000 due to the sale of equity and warrants in two portfolio companies totaling approximately $1.2 million offset by a loss of $1.4 million in one portfolio company.

We anticipate ten to twelve liquidity events from our portfolio companies in the current fiscal year. During the first six months of 2007 we have had two portfolio companies acquired, one completed its IPO, two portfolio companies filed registration statements for their IPO’s of which one was subsequently withdrawn, and three other portfolio companies are in various stages of M&A discussions.

For the three and six-month periods ended June 30, 2007, net unrealized investment appreciation totaled approximately $1.4 and $2.2 million respectively, compared to net unrealized depreciation of approximately $1.5 million for the three month period ended June 30, 2006 and net unrealized appreciation of $2.5 million for the six month period ended June 30, 2006. The net unrealized appreciation and depreciation of investments is based on portfolio asset valuations determined in good faith by our Board of Directors, based on the recommendations of the Valuation Committee. At June 30, 2007, gross unrealized appreciation totaled approximately $7.4 million in 24 of our portfolio investment companies and approximately $1.7 million of gross unrealized depreciation on 49 of our portfolio investment companies. At June 30, 2006, gross unrealized appreciation totaled approximately $4.5 million in 15 of our portfolio investment companies and approximately $1.3 million of gross unrealized depreciation on 26 of our portfolio investment companies. The net unrealized appreciation totaling approximately $1.4 million for the three month period ended June 30, 2007 was the result of a net increase in the warrant portfolio of $1.5 million, a decrease in value of the conversion right in one portfolio loan by approximately $97,000, a net depreciation on equity investments of approximately $214,000, a reversal of approximately $336,000 on warrants in two portfolio companies from an unrealized loss to a realized loss and an increase of approximately $170,000 related to the Citigroup warrant participation agreement. The net decrease in unrealized appreciation totaling approximately $1.5 million for the three-months ended June 30, 2006 was the result of the conversion of an unrealized gain on a warrant in one portfolio company to a realized gain upon the exercise and sale of the portfolio company’s common stock in the second quarter.

Income Taxes

We account for income taxes in accordance with the provisions of Statement of Financial Accounting Standards No. 109, Accounting for Income Taxes, which requires that deferred income taxes be determined based upon the estimated future tax effects of differences between the financial statement and tax basis of assets and liabilities given the provisions of the enacted tax law. Valuation allowances are used to reduce deferred tax assets to the amount likely to be realized.

We will elect to be treated as a RIC under Subchapter M of the Code for 2006 with the submission of our 2006 tax return. Such an election and qualification to be treated as a RIC requires that we comply with certain requirements contained in Subchapter M of the Code. For example, a RIC must meet certain requirements, including source-of-income, asset diversification and income distribution requirements. The income source requirement mandates that we receive 90% or more of our income from qualified earnings, typically referred to as “good income.” Qualified earnings may exclude such income as management fees received in connection with our SBIC or other potential outside managed funds and certain other fees.

We reported our financial position and results of operations under Subchapter C of the Code prior to 2006. As a C corporation, we accrued income tax expense on a quarterly basis until we were able to reasonably determine that we qualified as a RIC under requirements contained in Subchapter M of the Code. During 2006, we were able to reasonably

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determine that we could qualify as a RIC, and we accordingly reversed the income tax expense recorded during 2006 and adjusted through operations the $1.4 million deferred tax asset on our balance sheet at December 31, 2005. If we had been able to make the determination as of December 31, 2005, the impact of charging the deferred tax to operations would have reduced our NAV by approximately $0.15 per share.

Net Increase in Net Assets Resulting from Operations and Earnings Per Share

For the three and six-month periods ended June 30, 2007, net income totaled approximately $8.3 and $14.6 million, respectively, compared to net income of approximately $3.4 and $5.9 million for the three and six-month periods ended June 30, 2006. These changes are made up of the items previously described.

Basic net income per share for the three and six-month periods ended June 30, 2007 was $0.33 and $0.61 and fully diluted net income per share was $0.33 and $0.60, respectively, as compared to a basic net income per share of $0.26 and $0.52, and fully diluted net income per share of $0.26 and $0.51 for the three and six-month periods ended June 30, 2006, respectively.

Financial Condition, Liquidity, and Capital Resources

On October 20, 2006, we raised approximately $30.0 million, net of estimated issuance costs, in a public offering of 2.5 million shares of common stock delivered on October 25, 2006.

On December 12, 2006, we raised approximately $74.1 million, net of estimated issuance costs, in a public offering of 5.7 million shares of its common stock. On January 3, 2007, the underwriters exercised their over-allotment option and purchased an additional 840,000 shares of our common stock for additional net proceeds to the company of approximately $10.9 million.

During the first quarter of 2006, we received net proceeds of approximately $2.7 million from the exercise of the 5-Year Warrants.

On June 4, 2007, the Company raised approximately $102.2 million, net of issuance costs, in a public offering of 8.0 million shares of its common stock. On June 19, 2007, in connection with the same common stock issuance, the underwriters exercised their over-allotment option and purchased an additional 1.2 million shares of common stock for additional net proceeds of approximately $15.4 million.

For the six months ended June 30, 2007, net cash used in operating activities totaled approximately $119.7 million as compared to $9.6 million for the six months ended June 30, 2006. This increase was due primarily due to $180.7 million used for investment in our portfolio companies offset by $50.0 million of principal payments in first half of 2007 as compared $65.9 million used for investment in our portfolio companies offset by $48.8 million in principal repayments during the six months ended June 30 2006. Cash provided by investing activities totaled approximately $138,000 for the six months ended June 30, 2007 compared with net cash used in investing activities of $413,000 for the six months ended June 30, 2006. This change is primarily the result of a decrease in other long-term assets offset by the purchase of capital equipment. Net cash provided by financing activities totaled $110.7 million for the six months ended June 30, 2007 compared to $17.9 million for the six months ended June 30, 2006. This change is due to net proceeds from the sale of additional common stock of approximately $131.2 million, borrowings of $124.0 million on the credit facilities offset by repayment of $131.3 million and dividends paid of approximately $12.0 million in the six months ended June 30, 2007.

As of June 30, 2007, net assets totaled $390.0 million, with a net asset value per share of $12.05. We intend to generate additional cash primarily from future borrowings as well as cash flows from operations, including income earned from investment in our portfolio companies and, to a lesser extent, from the temporary investment of cash in U.S. government securities and other high-quality debt investments that mature in one year or less, principal payments from our investments and equity capital. Our primary use of funds will be for operations, investments in portfolio companies and cash distributions to holders of our common stock. After we have used our current capital resources, we expect to raise additional capital to support our future growth through future equity offerings, issuances of senior securities and/or future borrowings, to the extent permitted by the 1940 Act. As a result of the exemptive relief we received related to our SBA debt, we are able to exceed the 1:1 leverage ratio required by the 1940 Act. In order to fully leverage the Company, we would need to obtain additional credit. There can be no assurances that we will seek to, or be successful in leveraging the Company further.

As required by the 1940 Act, our asset coverage must be at least 200% after each issuance of senior securities. Our asset coverage as of June 30, 2007 was approximately 1,953%.

At June 30, 2007, we had approximately $7.5 million in cash and cash equivalents and available borrowing capacity of approximately $228.3 million under our Credit Facility, subject to existing terms and advance rates and $38.0 million under the SBA program. We primarily invest cash on hand in interest bearing deposit accounts.

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We anticipate that we will continue to fund our investment activities through a combination of debt and additional equity capital over the next year. As of June 30, 2007, we had $21.7 million outstanding under the Credit Facility and $12.0 million under the SBA program. Through March 30, 2007, advances under the Credit Facility carried interest at one-month LIBOR plus 165 basis points. On March 30, 2007, the interest on all borrowings was reduced to LIBOR plus a spread of 1.20%. On May 2, 2007, we amended the Credit Facility to extend the expiration date to May 1, 2008, increased the borrowing capacity under the facility to $250 million and included Deutsche Bank Securities Inc. as a participant along with Citigroup Markets Realty Corp. The credit facility is a one year facility and is renewable on May 1, 2008 with an interest rate of LIBOR plus a spread of 1.20%. We paid a structuring fee of $375,000 which will be expensed ratably through maturity. As of June 30, 2007, based on $251.7 million of eligible loans in the collateral pool and existing advance rates, we have access to approximately $116.8 million of borrowing capacity available under our $250.0 million securitized credit facility. In addition, Citigroup has an equity participation right of 10% of the realized gains on warrants collateralized under the Credit Facility. See Note 4 to the Consolidated Financial Statements for discussion of the participation right. We anticipate that portfolio fundings entered into in succeeding periods will allow us to utilize the full borrowing capacity of the Credit Facility.

At June 30, 2007 and December 31, 2006, we had the following borrowing capacity and outstandings:

HTII operates as a Small Business Investment Company under the SBIC program and borrows funds from the SBA against eligible previously approved investments and additional contributions to regulatory capital. As of June 30, 2007, HTII could draw up to $50.0 million of leverage. We made our first draw from the SBA on April 26, 2007 for $12.0 million. At June 30, 2007, we had a net investment of $46.5 million in HTII, and there are 19 outstanding investments with a fair value of $59.2 million. On July 31, 2007, we received approval from the SBA to increase our leverage by approximately $77.0 million to a total of $127.0 million, subject to certain regulatory requirements.

Off Balance Sheet Arrangements

In the normal course of business, we are party to financial instruments with off-balance sheet risk. These consist primarily of unfunded commitments to extend credit, in the form of loans, to our portfolio companies. Unfunded commitments to provide funds to portfolio companies will not be reflected on our balance sheet. Our unfunded commitments may be significant from time to time. As of June 30, 2007, we had unfunded commitments of approximately $111.1 million. These commitments will be subject to the same underwriting and ongoing portfolio maintenance as are the on-balance sheet financial instruments that we hold. Since these commitments may expire without being drawn upon, the total commitment amount does not necessarily represent future cash requirements.

Contractual Obligations

The following table shows our contractual obligations as of June 30, 2007:

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Borrowings

We, through Hercules Funding Trust I, an affiliated statutory trust, executed a securitized credit facility (the “Credit Facility”) with Citigroup Global Markets Realty Corp. (“Citigroup”). On December 6, 2006, we amended the Credit Facility with an agreement that increased the borrowing capacity under the facility to $150.0 million. On March 30, 2007, this increase was extended to July 31, 2007, and the interest on all borrowings was reduced to LIBOR plus a spread of 1.20%. On May 2, 2007, we amended the Credit Facility to extend the expiration date to May 1, 2008, increased the borrowing capacity under the facility to $250 million and included Deutsche Bank Securities Inc. as a participant along with Citigroup Markets Realty Corp. The credit facility is a one year facility and is renewable on May 1, 2008 with an interest rate of LIBOR plus a spread of 1.20%. We paid a structuring fee of $375,000 which will be expensed ratably through maturity. At June 30, 2007, we had $21.7 million outstanding under the Credit Facility.

The Credit Facility is collateralized by loans from our portfolio companies, and includes an advance rate of approximately 55% of eligible loans. The Credit Facility contains covenants that, among other things, require us to maintain a minimum net worth and to restrict the loans securing the Credit Facility to certain dollar amounts, to concentrations in certain geographic regions and industries, to certain loan grade classifications, to certain security interests, and to certain interest payment terms. Citigroup has an equity participation right through a warrant participation agreement on the pool of loans and warrants collateralized under the Credit Facility. Pursuant to the warrant participation agreement, we granted to Citigroup a 10% participation in all warrants held as collateral. However, no additional warrants are included in collateral subsequent to the facility amendment on May 2, 2007. As a result, Citigroup is entitled to 10% of the realized gains on the warrants until the realized gains paid to Citigroup pursuant to the agreement equals $3,750,000 (the “Maximum Participation Limit”). The Obligations under the warrant participation agreement continue even after the Credit Facility is terminated until the Maximum Participation Limit has been reached. During the six months ended June 30, 2007, we recorded an additional liability and reduced its unrealized gains by approximately $225,000 for Citigroup’s participation in unrealized gains in the warrant portfolio. The value of their participation right on unrealized gains in the related equity investments since inception of the agreement was approximately $602,000 at June 30, 2007 and is included in accrued liabilities and reduces the unrealized gain we recognized at June 30, 2007. We have paid Citigroup approximately $16,000 during the six months ended June 30, 2007 and $292,000 since inception of the agreement under the warrant participation agreement thereby reducing our realized gains.

We intend to aggregate pools of funded loans using the Credit Facility or other conduits that we may seek until a sufficiently large pool of funded loans is created which can then be securitized. We expect that any loans included in a securitization facility will be securitized on a non-recourse basis with respect to the credit losses on the loans. There can be no assurance that we will be able to complete this securitization strategy, or that it will be successful.

Under the SBA program we are able to draw up to $127.0 million, of which, we had drawn $12.0 million at June 30, 2007. We anticipate drawing the additional $115.0 million of availability over the next 6 to 12 months, subject to certain regulatory requirements.

Dividends

The following table summarizes our dividends declared and paid on all shares, including restricted stock, to date:

On August 2, 2007, we announced that our Board of Directors approved a dividend of $0.30 per share to shareholders of record as of August 16, 2007 and payable on September 17, 2007. Distributions in excess of our current and accumulated earnings and profits would be treated first as a return of capital to the extent of the stockholder’s tax basis, and any remaining distributions would be treated as a capital gain. The determination of the tax attributes of our distributions is made annually

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as of the end of our fiscal year based upon its taxable income for the full year and distributions paid for the full year, therefore a determination made on a quarterly basis may not be representative of the actual tax attributes of our distributions for a full year. If we determined the tax attributes of its distributions year-to-date as of June 30, 2007, 93.6% would be from ordinary income and 6.4% would be a return of capital for stockholders, however there can be no certainty to stockholders that this determination is representative of what the tax attributes of its 2007 distributions to stockholders will actually be. Stockholders should read any written disclosure accompanying a dividend payment carefully and should not assume that the source of any distribution is our taxable ordinary income or capital gains. Although there can be no assurances, we expect that dividends will be paid entirely out of earnings by the end of 2007.

Critical Accounting Policies

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and revenues and expenses during the period reported. On an ongoing basis, our management evaluates its estimates and assumptions, which are based on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. Actual results could differ from those estimates. Changes in our estimates and assumptions could materially impact our results of operations and financial condition.

Valuation of Portfolio Investments. The most significant estimate inherent in the preparation of our consolidated financial statements is the valuation of investments and the related amounts of unrealized appreciation and depreciation of investments recorded.

As a BDC, we invest primarily in illiquid securities, including debt and equity-related securities of private companies. Our investments are generally subject to some restrictions on resale and generally have no established trading market. Because of the type of investments that we make and the nature of our business, our valuation process requires an analysis of various factors. Our valuation methodology includes the examination of, among other things, the underlying investment performance, financial condition and market changing events that impact valuation.

At June 30, 2007, approximately 97% of our total assets represented investments in portfolio companies, of which greater than 98% are recorded at fair value by the Board of Directors. Value, as defined in Section 2(a) (41) of the 1940 Act, is (i) the market price for those securities for which a market quotation is readily available and (ii) for all other securities and assets, fair value is as determined in good faith by the Board of Directors. Since there is typically no readily available market value for the investments in our portfolio, we value substantially all of our investments at fair value as determined in good faith by our board pursuant to a valuation policy and a consistent valuation process. Due to the inherent uncertainty in determining the fair value of investments that do not have a readily available market value, the fair value of our investments determined in good faith by our board may differ significantly from the value that would have been used had a ready market existed for such investments, and the differences could be material.

There is no single standard for determining fair value in good faith. As a result, determining fair value requires that judgment be applied to the specific facts and circumstances of each portfolio investment. Unlike banks, we are not permitted to provide a general reserve for anticipated loan losses. Instead, we must determine the fair value of each individual investment on a quarterly basis. We will record unrealized depreciation on investments when we believe that an investment has decreased in value, including where collection of a loan or realization of an equity security is doubtful. Conversely, where appropriate, we will record unrealized appreciation if we believe that the underlying portfolio company has appreciated in value and, therefore, that our investment has also appreciated in value.

With respect to private debt and equity securities, each investment is valued using industry valuation benchmarks, and, where appropriate, the value is assigned a discount reflecting the illiquid nature of the investment, and our minority, non-control position. When a qualifying external event such as a significant purchase transaction, public offering, or subsequent debt or equity sale occurs, the pricing indicated by the external event will be used to corroborate our private debt or equity valuation.

Income Recognition. Interest income is recorded on the accrual basis and is recognized as earned in accordance with the contractual terms of the loan agreement to the extent that such amounts are expected to be collected. Original Issue Discount, “OID,” initially represents the value of detachable equity warrants obtained in conjunction with the acquisition of debt securities and is accreted into interest income over the term of the loan as a yield enhancement. When a loan becomes 90 days or more past due, or if management otherwise does not expect the portfolio company to be able to service its debt and other obligations, the Company will, as a general matter, place the loan on non-accrual status and cease recognizing interest income on that loan until all principal has been paid. However, Hercules may make exceptions to this policy if the investment has sufficient collateral value and is in the process of collection. As of June 30, 2007 we had one loan on non-accrual status. There were no loans on non-accrual status as of June 30, 2006,

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Paid-In-Kind Income. Contractual paid-in-kind (PIK) interest, which represents contractually deferred interest added to the loan balance that is generally due at the end of the loan term, is generally recorded on the accrual basis to the extent such amounts are expected to be collected. We will generally cease accruing PIK interest if there is insufficient value to support the accrual or we do not expect the portfolio company to be able to pay all principal and interest due.

Fee Income. Loan origination and commitment fees received in full at the inception of a loan are deferred and amortized into fee income as an enhancement to the related loan’s yield over the contractual life of the loan. Loan exit fees to be paid at the termination of the loan are accreted into fee income over the contractual life of the loan. These fees are reflected as adjustments to the loan yield in accordance with FAS 91, Accounting for Nonrefundable Fees and Costs Associated with Originating or Acquiring loans and Initial Direct Costs of Leases.

Stock-Based Compensation. We have issued and may, from time to time, issue additional stock options to employees under our 2004 Equity Incentive Plan. We follow Statement of Financial Accounting Standards No. 123 (revised 2004), Share-Based Payments (“FAS 123R”), to account for stock options granted. Under FAS 123R, compensation expense associated with stock-based compensation is measured at the grant date based on the fair value of the award and is recognized.

Recent Accounting Pronouncements

In June 2006, the FASB issued FASB Interpretation No. 48 (“FIN 48”), “Accounting for Uncertainty in Income Taxes—an interpretation of FASB Statement No. 109”, which clarifies the accounting for uncertainty in income taxes recognized in an enterprise’s financial statements in accordance with FASB Statement No. 109, Accounting for Income Taxes. FIN 48 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. FIN 48 also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure, and transition. FIN 48 became effective as of January 1, 2007.

We conducted a review of all open tax year’s income recognition and expense deduction filing positions and income tax returns filed (federal and state) for determination of any uncertain tax positions that may require recognition of a tax liability. This review encompassed an analysis of all book/tax difference adjustments as well as the timing of income and expense recognition for all tax years still open under the statute of limitations. As a result, we determined that it is more likely than not that each tax position taken on a previously filed return or to be taken on current tax returns will be sustained on examination based on the technical merits of the positions and therefore, no recognition of a tax liability on an uncertain tax position for FIN 48 purposes is anticipated.

In September 2006, the FASB issued Statement on Financial Accounting Standards No. 157, Fair Value Measurements. This standard clarifies the definition of fair value for financial reporting, establishes a framework for measuring fair value and requires additional disclosures about the use of fair value measurements. FAS 157 is effective for financial statements issued for fiscal years beginning after November 15, 2007 and interim periods within those fiscal years. As of June 30, 2007, we do not believe the adoption of FAS 157 will impact the amounts reported in the financial statements, however, additional disclosures will be required about the inputs used to develop the measurements of fair value and the effect of certain of the measurements reported in the statement of operations for a fiscal period.

Recent Developments

During the second quarter of 2007, one publicly traded portfolio company did not maintain an effective registration statement on file with the Securities and Exchange Commission as required by its warrant agreement. In July 2007, Hercules and the portfolio company reached a settlement agreement regarding the requirement to maintain an effective registration statement thereby allowing Hercules the option to exercise and sell the warrants in the portfolio at its discretion. In connection with the agreement, the portfolio company paid a one-time fee of $250,000.

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Interim Consolidated Financial Statements

HERCULES TECHNOLOGY GROWTH CAPITAL, INC.

CONSOLIDATED STATEMENTS OF ASSETS AND LIABILITIES

See notes to consolidated financial statements (unaudited).

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HERCULES TECHNOLOGY GROWTH CAPITAL, INC.

CONSOLIDATED SCHEDULE OF INVESTMENTS

June 30, 2007

(unaudited)

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HERCULES TECHNOLOGY GROWTH CAPITAL, INC.

CONSOLIDATED SCHEDULE OF INVESTMENTS

June 30, 2007

(Continued)

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HERCULES TECHNOLOGY GROWTH CAPITAL, INC.

CONSOLIDATED SCHEDULE OF INVESTMENTS

June 30, 2007

(Continued)

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HERCULES TECHNOLOGY GROWTH CAPITAL, INC.

CONSOLIDATED SCHEDULE OF INVESTMENTS

June 30, 2007

(Continued)