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Aug. 30, 2023

Entity Central Index Key

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0000831114

Amendment Flag

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false

Document Effective Date

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Aug. 30, 2023

Risk/Return [Heading]

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SUMMARY SECTION

Objective, Primary [Text Block]

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The investment objective of the F/m Opportunistic Income ETF (the “Fund”) is to maximize total return, including both income and appreciation, by identifying undervalued and opportunistic sectors and securities in the U.S. fixed income markets.

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Shares”). This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of Shares.

Portfolio Turnover [Heading]

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Portfolio Turnover

Expenses Restated to Reflect Current [Text]

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“Other Expenses” have been estimated to reflect expenses to be incurred during the current fiscal year.

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then hold or redeem all of your Shares at the end of those periods. The Example also assumes that: (1) your investment has a 5% return each year, and (2) the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy Narrative [Text Block]

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The Fund is an actively-managed exchange-traded fund (“ETF”) managed by F/m Investments, LLC d/b/a North Slope Capital, LLC (the “Adviser”) that seeks to achieve its investment objective by investing in fixed-income securities. Investments in fixed income securities may include debt securities of governments and government agencies, their agencies and instrumentalities, municipal and local debt, debt securities of corporations, convertible securities, commercial paper, mortgage- or asset-backed securities, preferred stock, and cash equivalents.

The Adviser allocates the Fund’s assets based upon its assessment of changing market, political and economic conditions. The Adviser will consider various factors, including evaluation of interest rate changes and credit risks. The Adviser has substantial latitude to invest across broad fixed income markets. The unconstrained investment approach may from time to time lead the Fund to have sizable allocations to particular markets, sectors and industries, and to have a sizable exposure to certain economic factors, such as credit risk or interest rate risk.

As of the date of this Prospectus, the Fund is expected to be significantly invested in the financial sector, industrials sector, and utilities sector, which means it will be more affected by the performance of such sectors than a fund that is not so significantly invested.

The Fund may invest up to 20% of its net assets in non-investment grade obligations (“junk bonds”). Non-investment grade obligations are generally rated at least BB+ or lower by at least one major rating agency at the time of purchase or, if unrated, determined by the Adviser to be comparable in quality to the rated obligations.

The Fund may invest up to 20% of its net assets in municipal securities issued by states, U.S. territories, and possessions, general obligation securities and revenue securities, including private activity bonds. Municipal securities include municipal bonds, notes, and leases. Municipal leases are securities that permit government issuers to acquire property and equipment without the security being subject to constitutional and statutory requirements for the issuance of long-term fixed income securities.

The Fund will also invest in securities of affiliated and unaffiliated ETFs that invest primarily in Fund eligible investments (collectively, “Underlying Funds”) to the extent permitted by applicable law and subject to certain restrictions.

The Fund invests in debt securities with a broad range of maturities and the Fund’s investments may have fixed or variable principal payments.

The Fund may also seek to increase its income by lending portfolio securities.

The Fund may obtain a significant portion of its investment exposure through the use of derivatives, such as futures, forwards, options, swaps (including, among others, interest rate and credit default swaps) and credit derivatives. The Fund intends to use derivatives to earn income and enhance returns, to manage or adjust the risk and duration exposure profile of the Fund, to replace more traditional direct investments, or to obtain exposure to certain markets. The use of these derivative transactions may allow the Fund to obtain net long or net negative (short) exposures to selected interest rates, durations or credit risks. The Adviser considers various factors, such as availability and cost, in deciding whether, when and to what extent to enter into derivative transactions.

The Fund has elected to qualify each year for treatment as a regulated investment company (“RIC”) under Subchapter M of Subtitle A, Chapter 1, of the Internal Revenue Code of 1986, as amended (the “Code”).

The Fund may sell an investment or reduce its position if:

● Revised economic forecasts or interest rate outlook requires a repositioning of the portfolio;

● The investment subsequently fails to meet the investment criteria;

● Changing credit profile and/or conditions result in an unacceptable risk condition;

● A more attractive investment is found; or

● The Adviser believes that the investment has reached its appreciated potential.

In order to respond to adverse market, economic, political, or other conditions, the Fund may assume a temporary defensive position that is inconsistent with its investment objective and principal investment strategy and invest without limit in cash and prime quality cash equivalents such as prime commercial paper and other money market instruments. A defensive position, taken at the wrong time, may have an adverse impact on the Fund’s performance. The Fund may be unable to achieve its investment objective during the employment of a temporary defensive measure.

Risk Narrative [Text Block]

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The value of the Fund’s investments may decrease, which will cause the value of the Shares to decrease. As a result, you may lose money on your investment in the Fund, and there can be no assurance that the Fund will achieve its investment objective. The Fund's principal risks are presented in alphabetical order to facilitate finding particular risks and comparing them with other funds. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears. Different risks may be more significant at different times depending on market conditions or other factors.

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Affiliated Fund Risk. Affiliated fund risk is the risk that the Adviser may select investments for the Fund based on its own financial interests or other business considerations rather than the Fund’s interests. The Adviser may be subject to potential conflicts of interest in selecting the Underlying Funds because the Underlying Funds pay an advisory fee to the Adviser based on their assets, the fees paid to the Adviser by some affiliated Underlying Funds may be higher than other Underlying Funds or the Underlying Funds may be in need of assets to enhance their appeal to other investors, liquidity and trading and/or to enable them to carry out their investment strategies. However, the Adviser is a fiduciary to the Fund and is legally obligated to act in the Fund’s best interest when selecting Underlying Funds.

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Convertible Securities Risk. The market price of a convertible security generally tends to behave like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Because a convertible security derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.

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Credit Risk. The value of your investment in the Fund may change in response to changes in the credit ratings of the Fund’s portfolio securities, including with respect to the Underlying Funds. Generally, investment risk and price volatility increase as a security’s credit rating declines. The financial condition of an issuer of a fixed income security held by the Fund or an Underlying Fund may cause it to default or become unable to pay interest or principal due on the security.

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Cyber Security Risk. Cyber security risk is the risk of an unauthorized breach and access to the Fund’s assets, Fund or customer data (including private shareholder information), or proprietary information, or the risk of an incident occurring that causes the Fund, the Underlying Funds, the Adviser, custodian, transfer agent, distributor and other service providers and financial intermediaries to suffer data breaches, data corruption or lose operational functionality or prevent the Fund’s investors from purchasing, redeeming or exchanging shares or receiving distributions. The Fund and the Adviser have limited ability to prevent or mitigate cyber security incidents affecting third-party service providers, the Underlying Funds, and the Underlying Funds’ third-party service providers and such third-party service providers may have limited indemnification obligations to the Fund, the Underlying Funds, or their respective investment advisers. Successful cyber-attacks or other cyber-failures or events affecting the Fund, the Underlying Funds or third-party service providers may adversely impact and cause financial losses to the Fund or its shareholders. Issuers of securities in which the Fund or the Underlying Funds invest are also subject to cyber security risks, and the value of these securities could decline if the issuers experience cyber-attacks or other cyber-failures.

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Derivatives Risk. A derivative is an instrument with a value based on the performance of an underlying currency, security, index or other reference asset. The use of derivatives involves risks different from, or greater than, the risks associated with investing in more traditional investments. Derivatives involve costs, may create leverage, and may be illiquid, volatile, and difficult to value. The Fund may not be able to close out or sell a derivative position at a particular time or at an anticipated price. The use of derivatives could also result in a loss if the counterparty to the transaction does not perform as promised, including because of such counterparty’s bankruptcy or insolvency. The investment results achieved by the use of derivatives by the Fund may not match or fully offset changes in the value of the underlying security, index or other reference asset that it was attempting to hedge or the investment opportunity the Fund was attempting to pursue.

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Duration Risk. Duration is a measure of the price sensitivity of a debt security or portfolio to interest rate changes. Duration risk is the risk that longer-duration debt securities will be more volatile and thus more likely to decline in price, and to a greater extent, in a rising interest rate environment than shorter-duration debt securities.

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ETF Risk. The Fund is an ETF, and, as a result of an ETF's structure, it is exposed to the following risks:

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Authorized Participants, Market Makers and Liquidity Providers Concentration Risk. Only an authorized participant (“AP”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of financial institutions that are institutional investors and may act as APs. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace. To the extent either of the following events occur, Shares may trade at a material discount to net asset value (“NAV”) and possibly face delisting: (i) APs exit the business or otherwise become unable to process creation and/or redemption orders and no other APs step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business or significantly reduce their business activities and no other entities step forward to perform their functions. These events, among others, may lead to the Shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than the NAV when you buy Shares in the secondary market, and you may receive less (or more) than NAV when you sell those Shares in the secondary market. A diminished market for an ETF's shares substantially increases the risk that a shareholder may pay considerably more or receive significantly less than the underlying value of the ETF shares bought or sold. In periods of market volatility, APs, market makers and/or liquidity providers may be less willing to transact in Shares.

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Secondary Market Trading Risk. Although Shares are listed on a national securities exchange, Nasdaq Stock Market, LLC (the “Exchange”), and may be traded on U.S. exchanges other than the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Shares on the Exchange may be halted. During periods of market stress, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.

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Shares May Trade at Prices Other Than NAV Risk. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund's NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.

To the extent the Fund invests in Underlying Funds, which are also ETFs, the Fund will be further exposed to the above ETF risks.

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Extension Risk. If interest rates rise, repayments of principal on certain debt securities, including, but not limited to, floating rate loans and mortgage-related securities, may occur at a slower rate than expected and the expected maturity of those securities could lengthen as a result. Securities that are subject to extension risk generally have a greater potential for loss when prevailing interest rates rise, which could cause their values to fall sharply. Interest-only and principal-only securities are especially sensitive to interest rate changes, which can affect not only their prices but can also change the income flows and repayment assumptions about those investments.

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Fixed-Income Market Risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular issuer, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates). An unexpected increase in Fund redemption requests, including requests from shareholders who may own a significant percentage of the Shares, which may be triggered by market turmoil or an increase in interest rates, could cause the Fund to sell its holdings at a loss or at undesirable prices and adversely affect the Fund’s share price and increase the Fund’s liquidity risk, Fund expenses and/or taxable distributions. To the extent the Fund invests in Underlying Funds that invest in fixed-income securities, the Fund will be further subject to fixed-income securities risks such as credit risk, duration risk, income risk, interest rate risk and rating agencies risk, as described herein.

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Income Risk. The Fund’s income may decline if interest rates fall. This decline in income can occur because the Fund or an Underlying Fund may subsequently invest in lower yielding bonds as bonds in its portfolio mature, are near maturity or are called, or the Fund or an Underlying Fund otherwise needs to purchase additional bonds.

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Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund or an Underlying Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s or an Underlying Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk. Very low or negative interest rates may impact the Fund’s or an Underlying Fund’s yield and may increase the risk that, if followed by rising interest rates, the Fund’s performance will be negatively impacted. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates. Such actions may negatively affect the value of debt instruments held by the Fund or an Underlying Fund, resulting in a negative impact on the Fund's performance and NAV. Any interest rate increases could cause the value of the Fund’s or an Underlying Fund’s investments in debt instruments to decrease. Rising interest rates may prompt redemptions from the Fund or an Underlying Fund, which may force the Fund or Underlying Fund to sell investments at a time when it is not advantageous to do so, which could result in losses.

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Liquidity Risk. Certain securities held by the Fund may be difficult (or impossible) to sell at the time and at the price the Adviser would like. As a result, the Fund may have to hold these securities longer than it would like and may forego other investment opportunities. There is the possibility that the Fund may lose money or be prevented from realizing capital gains if it cannot sell a security at a particular time and price.

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Management Risk. The Fund is subject to the risk of poor investment selection. In other words, the individual investments of the Fund may not perform as well as expected, and/or the Fund’s portfolio management practices may not work to achieve their desired result.

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Market Risk. The trading prices of securities and other instruments fluctuate in response to a variety of factors. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors including economic, political, financial, public health crises (such as epidemics or pandemics) or other disruptive events (whether real, expected or perceived) in the U.S. and global markets. As a result, an investor could lose money over short or long periods of time.

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Mortgage- and Asset-Backed Securities Risk. The Fund may invest in mortgage- and asset-backed securities, which represent “pools” of mortgages or other assets, including consumer loans or receivables held in trust. In a period of rising interest rates, these securities may exhibit additional volatility.

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Municipal Securities Risk. Adverse economic or political factors in the municipal bond market, including changes in the tax law, could impact the Fund in a negative manner.

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New Fund Risk. The Fund is a newly organized, management investment company with no operating history. In addition, there can be no assurance that the Fund will grow to, or maintain, an economically viable size, in which case the Board of Directors (the “Board”) of The RBB Fund, Inc. (the “Company”) may determine to liquidate the Fund.

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Non-Investment Grade (Junk Bond) Securities Risk. Below investment grade debt securities (also known as “junk bonds”) are speculative and involve a greater risk of default and price change due to changes in the issuer’s creditworthiness. The market prices of these debt securities may fluctuate more than the market prices of investment grade debt securities and may decline significantly in periods of general economic difficulty.

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Preferred Stock Risk. A preferred stock may decline in price, or fail to pay dividends when expected, because the issuer experiences a decline in its financial status. Preferred stocks often behave like debt securities, but have a lower payment priority than the issuer’s bonds or other debt securities. Therefore, they may be subject to greater credit risk than those of debt securities. Preferred stocks also may be significantly less liquid than many other securities, such as corporate debt or common stock.

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Rating Agencies Risk. Ratings are not an absolute standard of quality, but rather general indicators that reflect only the view of the originating rating agencies from which an explanation of the significance of such ratings may be obtained. There is no assurance that a particular rating will continue for any given period of time or that any such rating will not be revised downward or withdrawn entirely if, in the judgment of the agency establishing the rating, circumstances so warrant. A downward revision or withdrawal of such ratings, or either of them, may have an effect on the liquidity or market price of the securities in which the Fund or an Underlying Fund invests. The ratings of securitized assets may not adequately reflect the credit risk of those assets due to their structure.

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Reinvestment Risk. Reinvestment risk is the risk that income from the Fund’s portfolio will decline if and when the Fund reinvests the proceeds from the disposition of its portfolio securities at market interest rates that are below the portfolio’s current earnings rate. A decline in income could negatively affect the market price of the Shares.

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Sector Risk. To the extent the Fund, or an Underlying Fund in which the Fund invests, invests more heavily in particular sectors of the economy, its performance will be especially sensitive to developments that significantly affect those sectors.

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Financial Sector Risk. The operations and businesses of financial services companies are subject to extensive governmental regulation, the availability and cost of capital funds, and interest rate changes. General market downturns may affect financial services companies adversely.

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Industrials Sector Risk. Companies in the industrials sector could be affected by, among other things, government regulation, world events and economic conditions, insurance costs, and labor relations issues.

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Utilities Sector Risk. The utilities sector may be adversely affected by changing commodity prices, government regulation stipulating rates charged by utilities, increased tariffs, changes in tax laws, interest rate fluctuations and changes in the cost of providing specific utility services. The utilities industry is also subject to potential terrorist attacks, natural disasters and severe weather conditions, as well as regulatory and operational burdens associated with the operation and maintenance of nuclear facilities. Government regulators monitor and control utility revenues and costs, and therefore may limit utility profits.

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Securities Lending Risk. The Fund may lend portfolio securities to institutions, such as certain broker-dealers. The Fund may experience a loss or delay in the recovery of its securities if the borrowing institution breaches its agreement with the Fund.

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Underlying Funds Risk. Investing in Underlying Funds may result in duplication of expenses, including advisory fees, in addition to the Fund’s own expenses. The risk of owning an Underlying Fund generally reflects the risks of owning the underlying investments the Underlying Fund holds. The Fund may incur brokerage fees in connection with its purchase of ETF shares.

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U.S. Government Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government.

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Valuation Risk. The prices provided by the Fund’s pricing services or independent dealers or the fair value determinations made by the valuation committee of the Adviser may be different from the prices used by other mutual funds or from the prices at which securities are actually bought and sold. The prices of certain securities provided by pricing services may be subject to frequent and significant change, and will vary depending on the information that is available.

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Variable Rate Securities Risk. Variable rate securities provide for a periodic adjustment in the interest rate paid on the securities. The rate adjustment intervals may be regular and range from daily up to annually, or may be based on an event, such as a change in the prime rate. Variable rate securities may be subject to greater liquidity risk than other debt securities, and there may be limitations on the Fund’s ability to sell the securities at any given time.

Performance Narrative [Text Block]

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Performance Information: Performance information for the Fund is not included because the Fund had not commenced operations prior to the date of this Prospectus. Performance information will be available in the Prospectus once the Fund has at least one calendar year of performance. Updated performance information will be available on the Fund’s website at www.fmetfs.com.

Performance Availability Website Address [Text]

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www.fmetfs.com

Prospectus [Line Items]

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Management Fees (as a percentage of Assets)

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0.39%

Other Expenses (as a percentage of Assets):

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none

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Expense Example, with Redemption, 1 Year

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$ 40