MATSON MONEY U.S. EQUITY VI PORTFOLIO OF THE RBB FUND, INC.   FMVUX

SUMMARY PROSPECTUS

December 31, 2017

Before you invest, you may want to review the Fund's prospectus ("Prospectus"), which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund, including the statement of additional information and most recent reports to shareholders, online at http://hosted.rightprospectus.com/MatsonMoney. You can also get this information at no cost by calling (866) 780-0357 Ext. 3863 or by sending an e-mail request to FreeMarketFunds@matsonmoney.com. The Fund's Prospectus dated December 31, 2017 and the Fund's Statement of Additional Information ("SAI"), dated December 31, 2017, are incorporated by reference into this Summary Prospectus. 

Investment Objective

The Matson Money U.S. Equity VI Portfolio (the “Portfolio”) seeks long-term capital appreciation.

Expenses and Fees

This table describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio. This table does not reflect the fees and expenses associated with any variable annuity contract or variable life insurance policy that uses the Portfolio as an investment option. Had those fees and expenses been included, overall fees and expenses would be higher.

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fees	0.50%
Distribution and/or Service (12b-1) Fees	None
Other Expenses	0.31%
Acquired Fund Fees and Expenses(1)	0.27%
Total Annual Portfolio Operating Expenses	1.08%

(1) Acquired Fund Fees and Expenses are indirect fees and expenses that the Portfolio incurs from investing in the shares of other mutual funds, including money market funds and exchange traded funds. Please note that the amount of Total Annual Portfolio Operating Expenses shown in the above table will differ from the “Financial Highlights” section of the Prospectus, which reflects the operating expenses of the Portfolio and does not include indirect expenses such as Acquired Fund Fees and Expenses.

Example

This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. This Example does not reflect the fees and expenses associated with any variable annuity contract or variable life insurance policy that uses the Portfolio as an investment option. Had those fees and expenses been included, the costs shown below would be higher.

The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and that you sell your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio's operating expenses remain the same. Although your actual costs and returns might be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$110	$343	$595	$1,317

Portfolio Turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in Total Annual Portfolio Operating Expenses or in the Example, affect the Portfolio's performance. During the fiscal year ended August 31, 2017, the Portfolio's portfolio turnover rate was 21.00% of the average value of its portfolio.

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Summary of Principal Investment Strategies

The Portfolio pursues its investment objective by investing under normal circumstances at least 80% of its net assets, including any borrowings for investment purposes, in shares of registered, open-end investment companies and exchange-traded funds ("ETFs") (collectively, "investment companies") that have either adopted policies to invest at least 80% of their assets in equity securities, such as common stocks, preferred stocks or securities convertible into stocks, of U.S. companies, or invest substantially all of their assets in such equity securities. The Portfolio will diversify its investments by investing primarily in investment companies focusing on different segments of the equity markets, including large ("large-cap"), small ("small-cap") and micro-capitalization ("micro-cap") equity securities that the Portfolio's investment adviser ("Adviser") believes offer the prospect of long-term capital appreciation. The purchase of shares of investment companies may result in duplication of expenses, including advisory fees, in addition to the Portfolio's own expenses.

Under normal market conditions, the Adviser expects substantially all of the Portfolio's net assets to be invested in the securities of investment companies, including other investment companies funded by insurance company separate accounts, that invest in the types of securities described in each asset class below, with less than 2% of the net assets invested in cash or money market instruments.

U.S. Large Cap Value Asset Class: The underlying investment companies generally will purchase common stocks and other equity securities of large cap companies that the underlying investment adviser(s) determine to be value stocks at the time of purchase. An issuer's securities are considered value stocks primarily because they have a high book value in relation to their market value (a "book to market ratio"). In assessing value, the underlying investment adviser(s) may consider additional factors such as price to cash flow or price to earnings ratios as well as economic conditions and developments in the issuer's industry. The criteria used for assessing value are subject to change from time to time. As of December 2016, large cap companies generally were those companies with a market capitalization of $4.23 billion or greater. This dollar amount will change from time to time due to market conditions.

U.S. Small Cap Value Asset Class: The underlying investment companies generally will purchase common stocks and other equity securities of small cap companies that the underlying investment adviser(s) determine to be value stocks at the time of purchase. An issuer's securities are considered value stocks primarily because they have a high book value in relation to their market value (a "book to market ratio"). In assessing value, the underlying investment adviser(s) may consider additional factors such as price to cash flow or price to earnings ratios as well as economic conditions and developments in the issuer's industry. The criteria used for assessing value are subject to change from time to time. As of December 2016, small cap companies generally were those companies with a market capitalization of $4.23 billion or less. This dollar amount will change from time to time due to market conditions.

U.S. Large Company Asset Class: The underlying investment companies generally will purchase all of the stocks that comprise the S&P 500^® Index in approximately the proportions they are represented in the S&P 500^® Index. Generally, these are the U.S. stocks with the largest market capitalizations and, as a group, they represent approximately 75% of the total market capitalization of all publicly traded U.S. stocks.

U.S. Small Cap Asset Class: The underlying investment companies generally will purchase common stocks and other equity securities of small cap companies primarily based on market capitalization. As of December 2016, small cap companies were generally those with a market capitalization of $4.23 billion or less. This dollar amount will change from time to time due to market conditions. There may be some overlap in the companies in which the U.S. small cap asset class and the U.S. micro cap asset class invest.

U.S. Micro Cap Asset Class: The underlying investment companies generally will purchase common stocks and other equity securities of micro cap companies. As of December 2016, micro cap companies were generally those companies with a market capitalization of $2.14 billion or less. This dollar amount will change from time to time due to market conditions. There may be some overlap in the companies in which the U.S. micro cap asset class and the U.S. small cap asset class invest.

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The underlying investment companies may use derivatives, such as futures contracts and options on futures contracts for U.S. equity securities and indices, to gain market exposure on its uninvested cash pending investment in securities or to maintain liquidity to pay redemptions. Underlying index-based ETFs may use derivatives, including futures contracts, options on futures contracts, options and swaps to help the ETF track its underlying index.

The Portfolio reserves the right to hold up to 100% of its assets as a temporary defensive measure in cash and money market instruments such as U.S. government securities, bank obligations and commercial paper. To the extent the Portfolio employs a temporary defensive measure, the Portfolio may not achieve its investment objective. Periodically the Adviser will review the allocations for the Portfolio in each underlying investment company and may add or remove underlying investment companies and/or change the investment allocation percentages of the Portfolio in the underlying investment companies without notice to shareholders or the holders of the variable annuity or variable life insurance policies.

Summary of Principal Risks

As with all mutual funds, a shareholder is subject to the risk that his or her investment could lose money. An investment in the Portfolio involves the same investment risks as those of the underlying investment companies in which the Portfolio invests. These risks may adversely affect the Portfolio's net asset value ("NAV") and investment performance. The Portfolio is subject to the following principal risks:

• Stocks of large cap, small cap or micro cap companies in which the Portfolio's underlying investment companies invest or in which the Portfolio invests directly may temporarily fall out of favor with investors or may be more volatile than the rest of the U.S. market as a whole.

• The smaller the capitalization of a company, generally the less liquid its stock and the more volatile its price. Companies with smaller market capitalizations also tend to have unproven track records and are more likely to fail than companies with larger market capitalizations.

• Although the Portfolio will invest in other investment companies that follow a value oriented strategy, value stocks may perform differently from the market as a whole and such a strategy may cause the Portfolio at times to underperform equity funds that use other investment strategies.

• Companies in which the Portfolio's underlying investment companies invest may suffer unexpected losses or lower than expected earnings or their securities may become difficult or impossible to sell at the time and for the price that the underlying investment adviser(s) would like.

• The Adviser's judgment about the attractiveness or potential appreciation of a particular underlying investment company security could prove to be wrong or the Portfolio could miss out on an investment opportunity because the assets necessary to take advantage of such opportunity are tied up in less advantageous investments.

• Because under normal circumstances the Portfolio invests at least 80% of its net assets in shares of registered investment companies that emphasize investments in U.S. equity securities, the NAV of the Portfolio will change with changes in the share prices of the investment companies in which the Portfolio invests.

• There is a risk that large, small or micro capitalization stocks may not perform as well as other asset classes or the U.S. stock market as a whole. In the past, large, small and micro capitalization stocks have gone through cycles of doing better or worse than the stock market in general.

• There is a risk that the Portfolio, which is passively managed, may not perform as well as funds with more active methods of investment management, such as selecting securities based on economic, financial, and market analysis.

• The derivative instruments in which the underlying investment companies may invest are subject to a number of risks including liquidity, interest rate, market, credit and management risks, and the risk of improper valuation. Changes in the value of a derivative may not correlate perfectly with the underlying asset, rate or index, and it is possible to lose more than the principal amount invested.

• The performance of the Portfolio will depend on how successfully the investment adviser(s) to the underlying investment companies pursue their investment strategies.

More information about the Portfolio's investments and risks is contained under the section entitled "More About Each Portfolio's Investments and Risks."

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Performance Information

The chart below illustrates the performance of the Portfolio. The information shows you how the Portfolio's performance has varied year by year and provides some indication of the risks of investing in the Portfolio. The chart assumes reinvestment of dividends and distributions. Past performance (before and after taxes) does not necessarily indicate how the Portfolio will perform in the future. Updated information is available at www.matsonmoney.com or by calling (866) 780-0357 Ext. 3863.

Best and Worst Quarterly Performance (for the period reflected in the chart above)

Best Quarter: 10.24% (quarter ended December 31, 2016)

Worst Quarter: -9.83% (quarter ended September 30, 2015)

Year to Date Total Return as of September 30, 2017: 8.15%

Average Annual Total Returns

The following table compares the average annual total returns of the Portfolio before and after taxes for the past calendar year and since inception to the average total returns of a broad-based securities market index for the same periods.

	Average Annual Total Returns for the Periods Ended December 31, 2016
	1 Year	Since Inception (February 18, 2014)
Portfolio Returns Before Taxes	20.58%	7.80%
Portfolio Returns After Taxes on Distributions*	19.40%	7.01%
Portfolio Returns After Taxes on Distributions and Sale of Portfolio Shares*	12.63%	5.95%
Russell 2500® Index (reflects no deduction for fees, expenses or taxes)	17.59%	7.98%
Composite Index**	20.50%	9.79%

* After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns will depend on an investor's tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Portfolio shares through tax deferred arrangements, such as 401(k) plans or individual retirement accounts.

** The Composite Index is comprised of the S&P 500^® Index, Russell 1000^® Value Index, Russell 2000^® Index and Russell 2000^® Value Index, each weighted 25%, 25%, 25% and 25%, respectively. Additional information about the Composite Index can be found under the section entitled "More About Each Portfolio's Investments and Risks."

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Management of the Portfolio

Investment Adviser
Matson Money, Inc.

Portfolio Managers
Mark E. Matson: Chief Executive Officer and Director, since 1991
Steven B. Miller: President and Portfolio Manager, since 2004
Kenneth E. Gatliff: Portfolio Manager, since 2007

Purchase and Sale of Portfolio Shares

Portfolio shares are not sold directly to the public. Portfolio shares may be purchased and redeemed by separate accounts that fund variable annuity and variable life insurance contracts issued by participating insurance companies. Orders received from separate accounts to purchase or redeem Portfolio shares are effected on business days. Individual investors may purchase or redeem Portfolio shares indirectly through variable annuity contracts and variable life insurance policies offered through the separate accounts.

Taxes

Provided that the Portfolio and separate accounts investing in the Portfolio satisfy applicable tax requirements, the Portfolio will not be subject to federal tax, and the separate accounts will not be taxable on distributions from, or gains with respect to, the Portfolio. Special tax rules apply to life insurance companies, variable annuity contracts and variable life insurance contracts. For information on federal income taxation of owners of variable annuity or variable life insurance contracts, see the prospectus for the applicable contract.

Payments to Broker-Dealers and Other Financial Intermediaries

The Portfolio may pay participating insurance companies and securities dealers for the sale of Portfolio shares and other related services. These payments may create a conflict of interest by influencing the insurance company and your salesperson to recommend the Portfolio over another investment. Ask your salesperson or visit your insurance company's website for more information.

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