Item 1. Business.

What is USNG?

The United States Natural Gas Fund, LP (“USNG”) is a Delaware limited partnership organized on September 11, 2006. USNG maintains its main business office at 1999 Harrison Street, Suite 1530, Oakland, California 94612. USNG is a commodity pool that issues limited partnership interests (“units”) traded on the NYSE Arca, Inc. (the “NYSE Arca”). It operates pursuant to the terms of the Third Amended and Restated Agreement of Limited Partnership dated as of December 31, 2010 (as amended from time to time, the “LP Agreement”), which grants full management control to its general partner, United States Commodity Funds LLC (“USCF”).

The investment objective of USNG is for the daily changes in percentage terms of its units’ per unit net asset value (“NAV”) to reflect the daily changes in percentage terms of the spot price of natural gas delivered at the Henry Hub, Louisiana, as measured by the daily changes in the price of the futures contract for natural gas traded on the New York Mercantile Exchange (the “NYMEX”), that is the near month contract to expire, except when the near month contract is within two weeks of expiration, in which case it will be measured by the futures contract that is the next month contract to expire, less USNG’s expenses. It is not the intent of USNG to be operated in a fashion such that the per unit NAV will equal, in dollar terms, the spot price of natural gas or any particular futures contract based on natural gas. It is not the intent of USNG to be operated in a fashion such that its per unit NAV will reflect the percentage change of the price of any particular futures contract as measured over a time period greater than one day. USCF believes that it is not practical to manage the portfolio to achieve such an investment goal when investing in Futures Contracts (as defined below) and Other Natural Gas-Related Investments (as defined below). USNG’s units began trading on April 18, 2007. USCF is the general partner of USNG and is responsible for the management of USNG.

Who is USCF?

USCF is a single member limited liability company that was formed in the state of Delaware on May 10, 2005. Prior to June 13, 2008, USCF was known as Victoria Bay Asset Management, LLC. It maintains its main business office at 1999 Harrison Street, Suite 1530, Oakland, California 94612. USCF is a wholly owned subsidiary of Wainwright Holdings, Inc., a Delaware corporation (“Wainwright”). Mr. Nicholas Gerber (discussed below) controls Wainwright by virtue of his ownership of Wainwright’s shares. Wainwright is a holding company that previously owned an insurance company organized under Bermuda law (which has been liquidated) and a registered investment adviser firm named Ameristock Corporation, which has been distributed to the Wainwright shareholders. USCF is a member of the National Futures Association (the “NFA”) and registered as a commodity pool operator (“CPO”) with the Commodity Futures Trading Commission (the “CFTC”) on December 1, 2005.

USCF also serves as general partner or sponsor of the United States Oil Fund, LP (“USOF”), the United States 12 Month Oil Fund, LP (“US12OF”), the United States Gasoline Fund, LP (“UGA”), the United States Diesel-Heating Oil Fund, LP (formerly, the United States Heating Oil Fund, LP) (“USDHO”), the United States Short Oil Fund, LP (“USSO”), the United States 12 Month Natural Gas Fund, LP (“US12NG”), the United States Brent Oil Fund, LP (“USBO”), the United States Commodity Index Fund (“USCI”), the United States Copper Index Fund (“CPER”), the United States Agriculture Index Fund (“USAG”) and the United States Metals Index Fund (“USMI”). USOF, US12OF, UGA, USDHO, USSO, US12NG, USBO, USCI, CPER, USAG and USMI are actively operating funds and all are listed on the NYSE Arca. All funds listed previously are referred to collectively herein as the “Related Public Funds.” The Related Public Funds are subject to reporting requirements under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). For more information about each of the Related Public Funds, investors in USNG may call 1.800.920.0259 or visit www.unitedstatescommodityfunds.com or the SEC’s website at www.sec.gov.

USCF has also filed registration statements to register units of the United States Sugar Fund (“USSF”), the United States Natural Gas Double Inverse Fund (“UNGD”), the United States Gasoil Fund (“USGO”) and the United States Asian Commodities Basket Fund (“UAC”), each of which is a series of the United States Commodity Funds Trust I, and the US Golden Currency Fund (“HARD”), a series of the United States Currency Funds Trust. USSF, UNGD, USGO and HARD are currently not available to the public, as such funds are still in the process of review by various regulatory agencies which have regulatory authority over USCF and such funds. UAC has been declared effective by the regulatory agencies which have regulatory authority over USCF and UAC, but at the time of filing of this annual report on Form 10-K, UAC has not been made available to the public.

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USCF is required to evaluate the credit risk of USNG to the futures commission merchant (“FCM”), oversee the purchase and sale of USNG’s units by certain authorized purchasers (“Authorized Purchasers”), review daily positions and margin requirements of USNG and manage USNG’s investments. USCF also pays the fees of ALPS Distributors, Inc., which serves as the marketing agent for USNG (the “Marketing Agent”), and Brown Brothers Harriman & Co. (“BBH&Co.”), which serves as the administrator (the “Administrator”) and the custodian (the “Custodian”) for USNG.

Limited partners have no right to elect USCF as the general partner on an annual or any other continuing basis. If USCF voluntarily withdraws as general partner, however, the holders of a majority of USNG’s outstanding units (excluding for purposes of such determination units owned, if any, by the withdrawing USCF and its affiliates) may elect its successor. USCF may not be removed as general partner except upon approval by the affirmative vote of the holders of at least 66 and ² /3 percent of USNG’s outstanding units (excluding units owned, if any, by USCF and its affiliates), subject to the satisfaction of certain conditions set forth in the LP Agreement.

The business and affairs of USCF are managed by a board of directors (the “Board”), which is comprised of three management directors (the “Management Directors”), some of whom are also its executive officers, and three independent directors who meet the independent director requirements established by the NYSE Arca Equities Rules and the Sarbanes-Oxley Act of 2002. The Management Directors have the authority to manage USCF pursuant to its LLC Agreement, as amended from time to time. Through its Management Directors, USCF manages the day-to-day operations of USNG. The Board has an audit committee which is made up of the three independent directors (Peter M. Robinson, Gordon L. Ellis and Malcolm R. Fobes III). For additional information relating to the audit committee, please see “Item 10. Directors, Executive Officers and Corporate Governance – Audit Committee” in this annual report on Form 10-K.

How Does USNG Operate?

An investment in the units provides a means for diversifying an investor’s portfolio or hedging exposure to changes in natural gas prices. An investment in the units allows both retail and institutional investors to easily gain this exposure to the natural gas market in a transparent, cost-effective manner.

The net assets of USNG consist primarily of investments in futures contracts for natural gas, crude oil, diesel-heating oil, gasoline, and other petroleum-based fuels that are traded on the NYMEX, ICE Futures or other U.S. and foreign exchanges (collectively, “Futures Contracts”) and, to a lesser extent, in order to comply with regulatory requirements or in view of market conditions, other natural gas-related investments such as cash-settled options on Futures Contracts, forward contracts for natural gas, cleared swap contracts and non-exchange traded (“over-the-counter”) transactions that are based on the price of natural gas, oil and other petroleum-based fuels, Futures Contracts and indices based on the foregoing (collectively, “Other Natural Gas-Related Investments”). Market conditions that USCF currently anticipates could cause USNG to invest in Other Natural Gas-Related Investments include those allowing USNG to obtain greater liquidity or to execute transactions with more favorable pricing. For convenience and unless otherwise specified, Futures Contracts and Other Natural Gas-Related Investments collectively are referred to as “Natural Gas Interests” in this annual report on Form 10-K. USNG invests substantially the entire amount of its assets in Futures Contracts while supporting such investments by holding the amounts of its margin, collateral and other requirements relating to these obligations in short-term obligations of the United States of two years or less (“Treasuries”), cash and cash equivalents. The daily holdings of USNG are available on USNG’s website at www.unitedstatesnaturalgasfund.com.

The investment objective of USNG is for the daily changes in percentage terms of its units’ per unit NAV to reflect the daily changes in percentage terms of the spot price of natural gas delivered at the Henry Hub, Louisiana as measured by the daily changes in the price of the Futures Contract on natural gas traded on the NYMEX that is the near month contract to expire, except when the near month contract is within two weeks of expiration, in which case it will be measured by the futures contract that is the next month contract to expire (the “Benchmark Futures Contract”), less USNG’s expenses. It is not the intent of USNG to be operated in a fashion such that its per unit NAV will equal, in dollar terms, the spot price of natural gas or any particular futures contract based on natural gas. It is not the intent of USNG to be operated in a fashion such that its per unit NAV will reflect the percentage change of the price of any particular futures contract as measured over a time period greater than one day. USNG may invest in interests other than the Benchmark Futures Contract to comply with accountability levels and position limits. For a detailed discussion of accountability levels and position limits, see “Item 1. Business – What are Futures Contracts?” below in this annual report on Form 10-K.

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USCF employs a “neutral” investment strategy in order to track changes in the price of the Benchmark Futures Contract regardless of whether the price goes up or goes down. USNG’s “neutral” investment strategy is designed to permit investors generally to purchase and sell USNG’s units for the purpose of investing indirectly in natural gas in a cost-effective manner, and/or to permit participants in the natural gas or other industries to hedge the risk of losses in their natural gas-related transactions. Accordingly, depending on the investment objective of an individual investor, the risks generally associated with investing in natural gas and/or the risks involved in hedging may exist. In addition, an investment in USNG involves the risk that the changes in the price of USNG’s units will not accurately track the changes in the Benchmark Futures Contract, and that changes in the Benchmark Futures Contract will not closely correlate with changes in the spot prices of natural gas.

The Benchmark Futures Contract is changed from the near month contract to the next month contract over a four-day period. Each month, the Benchmark Futures Contract changes starting at the end of the day on the date two weeks prior to expiration of the near month contract for that month. During the first three days of the period, the applicable value of the Benchmark Futures Contract is based on a combination of the near month contract and the next month contract as follows: (1) day 1 consists of 75% of the then near month contract’s price plus 25% of the price of the next month contract, divided by 75% of the near month contract’s prior day’s price plus 25% of the price of the next month contract, (2) day 2 consists of 50% of the then near month contract’s price plus 50% of the price of the next month contract, divided by 50% of the near month contract’s prior day’s price plus 50% of the price of the next month contract, and (3) day 3 consists of 25% of the then near month contract’s price plus 75% of the price of the next month contract, divided by 25% of the near month contract’s prior day’s price plus 75% of the price of the next month contract. On day 4, the Benchmark Futures Contract is the next month contract to expire at that time and that contract remains the Benchmark Futures Contract until the beginning of the following month’s change in the Benchmark Futures Contract over a four-day period.

On each day during the four-day period, USCF anticipates it will “roll” USNG’s positions in Natural Gas Interests by closing, or selling, a percentage of USNG’s positions in Natural Gas Interests and reinvesting the proceeds from closing those positions in new Natural Gas Interests that reflect the change in the Benchmark Futures Contract.

The anticipated dates that the monthly four-day roll period will commence are posted on USNG’s website at www.unitedstatesnaturalgasfund.com, and are subject to change without notice.

USNG’s total portfolio composition is disclosed on its website each business day that the NYSE Arca is open for trading. The website disclosure of portfolio holdings is made daily and includes, as applicable, the name and value of each Natural Gas Interest, the specific types of Other Natural Gas-Related Investments and characteristics of such Other Natural Gas-Related Investments, the name and value of each Treasury and cash equivalent, and the amount of cash held in USNG’s portfolio. USNG’s website is publicly accessible at no charge. USNG’s assets used for margin and collateral are held in segregated accounts pursuant to the Commodity Exchange Act (the “CEA”) and CFTC regulations.

The units issued by USNG may only be purchased by Authorized Purchasers and only in blocks of 100,000 units called Creation Baskets. The amount of the purchase payment for a Creation Basket is equal to the aggregate NAV of the units in the Creation Basket. Similarly, only Authorized Purchasers may redeem units and only in blocks of 100,000 units called Redemption Baskets. The amount of the redemption proceeds for a Redemption Basket is equal to the aggregate NAV of units in the Redemption Basket. The purchase price for Creation Baskets, and the redemption price for Redemption Baskets are the actual NAV calculated at the end of the business day when a request for a purchase or redemption is received by USNG. The NYSE Arca publishes an approximate per unit NAV intra-day based on the prior day’s per unit NAV and the current price of the Benchmark Futures Contract, but the price of Creation Baskets and Redemption Baskets is determined based on the actual per unit NAV calculated at the end of the day.

While USNG issues units only in Creation Baskets, units are listed on the NYSE Arca and investors may purchase and sell units at market prices like any listed security.

What is USNG’s Investment Strategy?

In managing USNG’s assets, USCF does not use a technical trading system that issues buy and sell orders. USCF instead employs a quantitative methodology whereby each time a Creation Basket is sold, USCF purchases Natural Gas Interests, such as the Benchmark Futures Contract, that have an aggregate market value that approximates the amount of Treasuries and/or cash received upon the issuance of the Creation Basket.

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By remaining invested as fully as possible in Futures Contracts or Other Natural Gas-Related Investments, USCF believes that the daily changes in percentage terms in USNG’s per unit NAV will continue to closely track the daily changes in percentage terms in the price of the Benchmark Futures Contract. USCF believes that certain arbitrage opportunities result in the price of the units traded on the NYSE Arca closely tracking the per unit NAV of USNG. Additionally, Futures Contracts traded on the NYMEX have closely tracked the spot price of natural gas. Based on these expected interrelationships, USCF believes that the changes in the price of USNG’s units traded on the NYSE Arca have closely tracked and will continue to closely track the changes in the spot price of natural gas. For performance data relating to USNG’s ability to track its benchmark, see “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations — Tracking USNG’s Benchmark” in this annual report on Form 10-K.

USCF endeavors to place USNG’s trades in Futures Contracts and Other Natural Gas-Related Investments and otherwise manage USNG’s investments so that “A” will be within plus/minus 10 percent of “B,” where:

USCF believes that market arbitrage opportunities will cause the daily changes in USNG’s unit price on the NYSE Arca to closely track the daily changes in USNG’s per unit NAV. USCF believes that the net effect of these two expected relationships and the relationships described above between USNG’s per unit NAV and the Benchmark Futures Contract will be that the daily changes in the price of USNG’s units on the NYSE Arca will closely track, in percentage terms, the changes in the spot price of a barrel of natural gas, less USNG’s expenses. For performance data relating to USNG’s ability to track its benchmark, see “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Tracking USNG’s Benchmark” in this annual report on Form 10-K.

The specific Futures Contracts purchased depend on various factors, including a judgment by USCF as to the appropriate diversification of USNG’s investments in futures contracts with respect to the month of expiration, and the prevailing price volatility of particular contracts. While USCF has made significant investments in NYMEX Futures Contracts, for various reasons, including the ability to enter into the precise amount of exposure to the natural gas market, position limits or other regulatory requirements limiting USNG’s holdings, and market conditions, it may invest in Futures Contracts traded on other exchanges or invest in Other Natural Gas-Related Investments. To the extent that USNG invests in Other Natural Gas-Related Investments, it would prioritize investments in contracts and instruments that are economically equivalent to the Benchmark Futures Contract, including cleared swaps that satisfy such criteria, and then, to a lesser extent, it would invest in other types of cleared swaps and other contracts, instruments and non-cleared swaps, such as swaps in the over-the-counter market. If USNG is required by law or regulation, or by one of its regulators, including a futures exchange, to reduce its position in the Futures Contract to the applicable position limit or to a specified accountability level or if market conditions dictate it would be more appropriate to invest in Other Natural Gas-Related Investments, a substantial portion of USNG’s assets could be invested in accordance with such priority in Other Natural Gas-Related Investments that are intended to replicate the return on the Benchmark Futures Contract. As USNG’s assets reach higher levels, it is more likely to exceed position limits, accountability levels or other regulatory limits and, as a result, it is more likely that it will invest in accordance with such priority in Other Natural Gas-Related Investments at such higher levels. In addition, market conditions that USCF currently anticipates could cause USNG to invest in Other Natural Gas-Related Investments include those allowing USNG to obtain greater liquidity or to execute transactions with more favorable pricing. See “Item 1. Business – Regulation” in this annual report on Form 10-K for a discussion of the potential impact of the Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”) on USNG’s ability to invest in over-the-counter transactions and cleared swaps.

USCF may not be able to fully invest USNG’s assets in the Futures Contract having an aggregate notional amount exactly equal to USNG’s NAV. For example, as standardized contracts, the Futures Contracts are for a specified amount of a particular commodity, and USNG’s NAV and the proceeds from the sale of a Creation Basket are unlikely to be an exact multiple of the amounts of those contracts. As a result, in such circumstances, USNG may be better able to achieve the exact amount of exposure to changes in price of the Benchmark Futures Contract through the use of Other Natural Gas-Related Investments, such as over-the-counter contracts that have better correlation with changes in price of the Benchmark Futures Contract.

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USNG anticipates that to the extent it invests in Futures Contracts other than contracts on natural gas (such as futures contracts for light, sweet crude oil, diesel-heating oil and other petroleum-based fuels) and Other Natural Gas-Related Investments, it will enter into various non-exchange-traded derivative contracts to hedge the short-term price movements of such Futures Contracts and Other Natural Gas-Related Investments against the current Benchmark Futures Contract.

USCF does not anticipate letting USNG’s Futures Contracts expire and taking delivery of the underlying commodity. Instead, USCF closes existing positions, e.g., when it changes the Benchmark Futures Contract or Other Natural Gas-Related Investments or it otherwise determines it would be appropriate to do so and reinvests the proceeds in new Futures Contracts or Other Natural Gas-Related Investments. Positions may also be closed out to meet orders for Redemption Baskets and in such case proceeds for such baskets will not be reinvested.

What is the Natural Gas Market and the Petroleum-Based Fuel Market?

Natural Gas . Natural gas accounts for almost a quarter of U.S. energy consumption. The price of natural gas is established by the supply and demand conditions in the North American market, and more particularly, in the main refining center of the U.S. Gulf Coast. The natural gas market essentially constitutes an auction, where the highest bidder wins the supply. When markets are “strong” ( i.e ., when demand is high and/or supply is low), the bidder must be willing to pay a higher premium to capture the supply. When markets are “weak” ( i.e ., when demand is low and/or supply is high), a bidder may choose not to outbid competitors, waiting instead for later, possibly lower priced, supplies. Demand for natural gas by consumers, as well as agricultural, manufacturing and transportation industries, determines overall demand for natural gas. Since the precursors of product demand are linked to economic activity, natural gas demand will tend to reflect economic conditions. However, other factors such as weather significantly influence natural gas demand.

The NYMEX is the world’s largest physical commodity futures exchange and the dominant market for the trading of energy and precious metals. The Benchmark Futures Contract trades in units of 10,000 MMBtu and is based on delivery at the Henry Hub in Louisiana, the nexus of 16 intra- and interstate natural gas pipeline systems that draw supplies from the region’s prolific gas deposits. The pipelines serve markets throughout the U.S. East Coast, the Gulf Coast, the Midwest, and up to the Canadian border. Because of the volatility of natural gas prices, a vigorous basis market has developed in the pricing relationships between the Henry Hub and other important natural gas market centers in the continental United States and Canada. The NYMEX makes available for trading a series of basis swap futures contracts that are quoted as price differentials between approximately 30 natural gas pricing points and the Henry Hub. The basis contracts trade in units of 2,500 MMBtu on the New York Mercantile Exchange ClearPort ^® trading platform. The New York Mercantile Exchange ClearPort ^® is an electronic trading platform through which a slate of energy futures contracts are available for competitive trading. Transactions can also be consummated off-NYMEX and submitted to the NYMEX for clearing via the NYMEX ClearPort ^® clearing website as an exchange of futures for physicals or an exchange of futures for swaps transactions.

Light, Sweet Crude Oil . Crude oil is the world’s most actively traded commodity. The futures contracts for light, sweet crude oil that are traded on the NYMEX are the world’s most liquid forum for crude oil trading, as well as the world’s largest volume futures contract trading on a physical commodity. Due to the liquidity and price transparency of oil futures contracts, they are used as a principal international pricing benchmark. The futures contracts for light, sweet crude oil trade on the NYMEX in units of 1,000 U.S. barrels (42,000 gallons) and, if not closed out before maturity, will result in delivery of oil to Cushing, Oklahoma, which is also accessible to the international spot markets via pipelines.

Demand for petroleum products by consumers, as well as agricultural, manufacturing and transportation industries, determines demand for crude oil by refiners. Since the precursors of product demand are linked to economic activity, crude oil demand will tend to reflect economic conditions. However, other factors such as weather also influence product and crude oil demand.

Crude oil supply is determined by both economic and political factors. Oil prices (along with drilling costs, availability of attractive prospects for drilling, taxes and technology, among other factors) determine exploration and development spending, which influence output capacity with a lag. In the short run, production decisions by the Organization of Petroleum Exporting Countries (“OPEC”) also affect supply and prices. Oil export embargoes and the current conflict in Iraq represent other routes through which political developments move the market. It is not possible to predict the aggregate effect of all or any combination of these factors.

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Diesel-Heating Oil. Diesel-heating oil, also known as No. 2 fuel oil, accounts for 25% of the yield of a barrel of crude oil, the second largest “cut” from oil after gasoline. The diesel-heating oil futures contract listed and traded on the NYMEX trades in units of 42,000 gallons (1,000 barrels) and is based on delivery in the New York harbor, the principal cash market center. The ICE Futures also offers a Diesel-Heating Oil Futures Contract which trades in units of 42,000 U.S. gallons (1,000 barrels). The Diesel-Heating Oil Futures Contract is cash-settled against the prevailing market price for diesel-heating oil delivered to the New York Harbor.

Gasoline. Gasoline is the largest single volume refined product sold in the U.S. and accounts for almost half of national oil consumption. The gasoline futures contract listed and traded on the NYMEX trades in units of 42,000 gallons (1,000 barrels) and is based on delivery at petroleum products terminals in the New York harbor, the major East Coast trading center for imports and domestic shipments from refineries in the New York harbor area or from the Gulf Coast refining centers. The price of gasoline has historically been volatile.

What are Futures Contracts?

Futures Contracts are agreements between two parties. One party agrees to buy a commodity such as natural gas from the other party at a later date at a price and quantity agreed upon when the contract is made. Futures Contracts are traded on futures exchanges, including the NYMEX. For example, the Benchmark Futures Contract is traded on the NYMEX in units of 10,000 MMBtu. Futures Contracts traded on the NYMEX are priced by floor brokers and other exchange members both through an “open outcry” of offers to purchase or sell the contracts and through an electronic, screen-based system that determines the price by matching electronically offers to purchase and sell. Additional risks of investing in Futures Contracts are included in “Item 1A. Risk Factors” in this annual report on Form 10-K.

Impact of Accountability Levels, Position Limits and Price Fluctuation Limits.  Futures contracts include typical and significant characteristics. Most significantly, the CFTC and U.S. designated contract markets such as the NYMEX have established accountability levels and position limits on the maximum net long or net short futures contracts in commodity interests that any person or group of persons under common trading control (other than as a hedge, which an investment by USNG is not) may hold, own or control. The net position is the difference between an individual or firm’s open long contracts and open short contracts in any one commodity. In addition, most U.S.-based futures exchanges, such as the NYMEX, limit the daily price fluctuation for futures contracts. Currently, the ICE Futures imposes position and accountability limits that are similar to those imposed by U.S.-based futures exchanges and also limits the maximum daily price fluctuation, while some other non-U.S. futures exchanges have not adopted such limits.

The accountability levels for the Benchmark Futures Contract and other Futures Contracts traded on U.S.-based futures exchanges, such as the NYMEX, are not a fixed ceiling, but rather a threshold above which the NYMEX may exercise greater scrutiny and control over an investor’s positions. The current accountability level for investments for any one-month in the Benchmark Futures Contract is 6,000 net contracts. In addition, the NYMEX imposes an accountability level for all months of 12,000 net futures contracts for natural gas. In addition, the ICE Futures maintains the same accountability levels, position limits and monitoring authority for its natural gas contract as the NYMEX. If USNG and the Related Public Funds exceed these accountability levels for investments in the futures contract for natural gas, the NYMEX and ICE Futures will monitor such exposure and may ask for further information on their activities, including the total size of all positions, investment and trading strategy, and the extent of liquidity resources of USNG and the Related Public Funds. If deemed necessary by the NYMEX and/or ICE Futures, USNG could be ordered to reduce its aggregate position back to the accountability level. As of December 31, 2012, USNG held 17,891 NYMEX Natural Gas Futures NG contracts and 17,952 NYMEX Natural Gas Futures NN contracts. As of December 31, 2012, USNG held 30,192 natural gas cleared-swap contracts traded on the ICE Futures. USNG exceeded accountability levels of the NYMEX during the year ended December 31, 2012, when it held a maximum of 25,065 Natural Gas Futures NG contracts and 19,952 Natural Gas Financial Futures NN contracts, exceeding both the “any” and “all” month limits. No action was taken by the NYMEX and USNG did not reduce the number of Futures Contracts held as a result. USNG exceeded accountability levels of ICE Futures during the year ended December 31, 2012, when it held a maximum of 44,808 natural gas cleared swap contracts, exceeding the “any” month limit. No action was taken by ICE Futures and USNG did not reduce the number of cleared swap contracts held as a result.

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Position limits differ from accountability levels in that they represent fixed limits on the maximum number of futures contracts that any person may hold and cannot allow such limits to be exceeded without express CFTC authority to do so. In addition to accountability levels and position limits that may apply at any time, the NYMEX and ICE Futures impose position limits on contracts held in the last few days of trading in the near month contract to expire. It is unlikely that USNG will run up against such position limits because USNG’s investment strategy is to close out its positions and “roll” from the near month contract to expire to the next month contract during a four-day period beginning two weeks from expiration of the contract. For the year ended December 31, 2012, USNG did not exceed any position limits imposed by the NYMEX and ICE Futures.

In late 2011, the CFTC adopted rules that impose new position limits on Referenced Contracts (as defined below) involving 28 energy, metals and agricultural commodities (the “Position Limit Rules”). The Position Limit Rules were scheduled to become effective on October 12, 2012. However, on September 28, 2012, the United States District Court for the District of Columbia vacated these regulations on the basis of ambiguities in the provisions of the CEA (as modified by the Dodd-Frank Act) upon which the regulations were based. In its September 28, 2012 decision, the court remanded the Position Limit Rules to the CFTC with instructions to use its expertise and experience to resolve the ambiguities in the statute. On November 15, 2012, the CFTC indicated that it will move forward with an appeal of the District Court’s decision to vacate the Position Limit Rules. At this time, it is not possible to predict how the CFTC’s appeal could affect USNG, but it may be substantial and adverse. Furthermore, until such time as the appeal is resolved or, if applicable revisions to the Position Limit Rules are proposed and adopted, the regulatory architecture in effect prior to the enactment of the Position Limit Rules will govern transactions in commodities and related derivatives (collectively, “Referenced Contracts). Under that system, the CFTC enforces federal limits on speculation in agricultural products (e.g., corn, wheat and soy), while futures exchanges enforce position limits and accountability levels for agricultural and certain energy products (e.g., oil and natural gas). As a result, USNG may be limited with respect to the size of its investments in any commodities subject to these limits. Finally, subject to certain narrow exceptions, the vacated Position Limit Rules would have required the aggregation, for purposes of the position limits, of all positions in the 28 Referenced Contracts held by a single entity and its affiliates, regardless of whether such position existed on U.S. futures exchanges, non-U.S. futures exchanges, in cleared swaps or in over-the-counter swaps. The CFTC is presently considering new aggregation rules, under a rulemaking proposal that is distinct from the Position Limit Rules. At this time, it is unclear how any modified aggregation rules may affect USNG, but it may be substantial and adverse. By way of example, the aggregation rules in combination with any potential revised Position Limit Rules may negatively impact the ability of USNG to meet its investment objectives through limits that may inhibit USCF’s ability to sell additional Creation Baskets of USNG. See “Commodity Interest Markets – Regulation” in this annual report on Form 10-K for information regarding the Dodd-Frank Act.

Price Volatility . The price volatility of Futures Contracts generally has been historically greater than that for traditional securities such as stocks and bonds. Price volatility often is greater day-to-day as opposed to intra-day. Futures Contracts tend to be more volatile than stocks and bonds because price movements for natural gas are more currently and directly influenced by economic factors for which current data is available and are traded by natural gas futures traders throughout the day. Because USNG invests a significant portion of its assets in Futures Contracts, the assets of USNG, and therefore the prices of USNG units, may be subject to greater volatility than traditional securities.

Marking-to-Market Futures Positions . Futures Contracts are marked to market at the end of each trading day and the margin required with respect to such contracts is adjusted accordingly. This process of marking-to-market is designed to prevent losses from accumulating in any futures account. Therefore, if USNG’s futures positions have declined in value, USNG may be required to post “variation margin” to cover this decline. Alternatively, if USNG’s futures positions have increased in value, this increase will be credited to USNG’s account.

Why Does USNG Purchase and Sell Futures Contracts?

USNG’s investment objective is for the daily changes in percentage terms of its units’ per unit NAV to reflect the daily changes in percentage terms of the Benchmark Futures Contract, less USNG’s expenses. USNG invests primarily in Futures Contracts. USNG seeks to have its aggregate NAV approximate at all times the aggregate market value of the Futures Contracts (or Other Natural Gas-Related Investments) it holds.

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In connection with investing in Futures Contracts and Other Natural Gas-Related Investments, USNG holds Treasuries, cash and/or cash equivalents that serve as segregated assets supporting USNG’s positions in Futures Contracts and Other Natural Gas-Related Investments. For example, the purchase of a Futures Contract with a notional value of $10 million would not require USNG to pay $10 million upon entering into the contract; rather, only a margin deposit, generally of 5% to 30% of the stated value of the Futures Contract, would be required. To secure its Futures Contract obligations, USNG would deposit the required margin with the FCM and would separately hold, through its Custodian, Treasuries, cash and/or cash equivalents in an amount equal to the balance of the current market value of the contract, which at the contract’s inception would be $10 million minus the amount of the margin deposit, or $9.0 million (assuming a 10% margin).

As a result of the foregoing, typically 5% to 30% of USNG’s assets are held as margin in segregated accounts with a FCM. In addition to the Treasuries and cash it posts with the FCM for the Futures Contracts it owns, USNG may hold, through the Custodian, Treasuries, cash and/or cash equivalents that can be posted as additional margin or as other collateral to support its over-the-counter contracts. USNG earns income from the Treasuries and/or cash equivalents that it purchases, and on the cash it holds through the Custodian or FCM. USNG anticipates that the earned income will increase the NAV and limited partners’ capital contribution accounts. USNG reinvests the earned income, holds it in cash, or uses it to pay its expenses. If USNG reinvests the earned income, it makes investments that are consistent with its investment objective.

What are the Trading Policies of USNG?

Liquidity

USNG invests only in Futures Contracts and Other Natural Gas-Related Investments that, in the opinion of USCF, are traded in sufficient volume to permit the ready taking and liquidation of positions in these financial interests and Other Natural Gas-Related Investments that, in the opinion of USCF, may be readily liquidated with the original counterparty or through a third party assuming the position of USNG.

Spot Commodities

While the Futures Contracts traded on the NYMEX can be physically settled, USNG does not intend to take or make physical delivery. USNG may from time to time trade in Other Natural Gas-Related Investments, including contracts based on the spot price of natural gas.

Leverage

USCF endeavors to have the value of USNG’s Treasuries, cash and cash equivalents, whether held by USNG or posted as margin or other collateral, at all times approximate the aggregate market value of its obligations under its Futures Contracts and Other Natural Gas-Related Investments. Commodity pools’ trading positions in futures contracts or other related investments are typically required to be secured by the deposit of margin funds that represent only a small percentage of a futures contract’s (or other commodity interest’s) entire market value. While USCF has not and does not intend to leverage USNG’s assets, it is not prohibited from doing so under the LP Agreement.

Borrowings

Borrowings are not used by USNG, unless USNG is required to borrow money in the event of physical delivery, if USNG trades in cash commodities, or for short-term needs created by unexpected redemptions.

Over-the-Counter Derivatives (Including Spreads and Straddles)

In addition to Futures Contracts, there are also a number of listed options on the Futures Contracts on the principal futures exchanges. These contracts offer investors and hedgers another set of financial vehicles to use in managing exposure to the natural gas market. Consequently, USNG may purchase options on natural gas Futures Contracts on these exchanges in pursuing its investment objective.

In addition to the Futures Contracts and options on the Futures Contracts, there also exists an active non-exchange-traded market in derivatives tied to natural gas. These derivatives transactions (also known as over-the-counter contracts) are usually entered into between two parties in private contracts. Unlike most of the exchange-traded Futures Contracts or exchange-traded options on the Futures Contracts, each party to such contract bears the credit risk of the other party, i.e. , the risk that the other party may not be able to perform its obligations under its contract.

To reduce the credit risk that arises in connection with such contracts, USNG will generally enter into an agreement with each counterparty based on the Master Agreement published by the International Swaps and Derivatives Association, Inc. (“ISDA”) that provides for the netting of its overall exposure to its counterparty.

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USCF assesses or reviews, as appropriate, the creditworthiness of each potential or existing counterparty to an over-the-counter contract pursuant to guidelines approved by USCF’s Board.

USNG may employ spreads or straddles in its trading to mitigate the differences in its investment portfolio and its goal of tracking the price of the Benchmark Futures Contract. USNG would use a spread when it chooses to take simultaneous long and short positions in futures written on the same underlying asset, but with different delivery months.

USNG has employed hedging methods to the extent it invested in fully-collateralized over-the-counter swap transactions designed to track percentage changes in the price of the Benchmark Futures Contract. USNG has been exposed to counterparty risk on these fully-collateralized over-the-counter swap transactions.

Pyramiding

USNG has not and will not employ the technique, commonly known as pyramiding, in which the speculator uses unrealized profits on existing positions as variation margin for the purchase or sale of additional positions in the same or another commodity interest.

Who are the Service Providers?

In its capacity as the Custodian for USNG, BBH&Co. holds USNG’s Treasuries, cash and/or cash equivalents pursuant to a custodial agreement. BBH&Co. is also the registrar and transfer agent for the units. In addition, in its capacity as Administrator for USNG, BBH&Co. performs certain administrative and accounting services for USNG and prepares certain SEC, NFA and CFTC reports on behalf of USNG. USCF pays BBH&Co.’s fees for these services.

BBH&Co.’s principal business address is 50 Milk Street, Boston, MA 02109-3661. BBH&Co., a private bank founded in 1818, is neither a publicly held company nor insured by the Federal Deposit Insurance Corporation. BBH&Co. is authorized to conduct a commercial banking business in accordance with the provisions of Article IV of the New York State Banking Law, New York Banking Law §§160–181, and is subject to regulation, supervision, and examination by the New York State Department of Financial Services. BBH&Co. is also licensed to conduct a commercial banking business by the Commonwealths of Massachusetts and Pennsylvania and is subject to supervision and examination by the banking supervisors of those states.

USNG also employs ALPS Distributors, Inc. as the Marketing Agent. USCF pays the Marketing Agent an annual fee. In no event may the aggregate compensation paid to the Marketing Agent and any affiliate of USCF for distribution-related services in connection with the offering of units exceed ten percent (10%) of the gross proceeds of the offering.

ALPS’s principal business address is 1290 Broadway, Suite 1100, Denver, CO 80203. ALPS is the marketing agent for USNG. ALPS is a broker-dealer registered with the Financial Industry Regulatory Authority (“FINRA”) and a member of the Securities Investor Protection Corporation.

UBS Securities LLC (“UBS Securities”) is USNG’s FCM. USNG and UBS Securities have entered into an Institutional Futures Client Account Agreement. This agreement requires UBS Securities to provide services to USNG in connection with the purchase and sale of Natural Gas Interests that may be purchased or sold by or through UBS Securities for USNG’s account. USNG pays UBS Securities’ commissions for executing and clearing trades on behalf of USNG.

UBS Securities’ principal business address is 677 Washington Blvd, Stamford, CT 06901. UBS Securities is a futures clearing broker for USNG . UBS Securities is registered in the U.S. with FINRA as a broker-dealer and with the CFTC as a FCM. UBS Securities is a member of various U.S. futures and securities exchanges.

UBS is and has been a defendant in numerous legal proceedings, including actions brought by regulatory organizations and government agencies, relating to its securities and commodities business that allege various violations of federal and state securities laws. UBS AG, the ultimate parent company to UBS Securities, files annual reports and quarterly reports to the SEC in which it discloses material information about matters involving, but not limited to, UBS Securities, including information about any material litigation or regulatory investigations (https://www.ubs.com/global/en/about_ubs/investor_relations/quarterly_reporting/2011.html). Actions with respect to UBS Securities’ FCM business are publicly available on the website of the National Futures Association (http://www.nfa.futures.org/).

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On June 27, 2007, the Securities Division of the Secretary of the Commonwealth of Massachusetts (“Massachusetts Securities Division”) filed an administrative complaint (the “Complaint”) and notice of adjudicatory proceeding against UBS Securities, captioned In The Matter of UBS Securities, LLC, Docket No. E-2007-0049, which alleged that UBS Securities violated the Massachusetts Uniform Securities Act (the “Act”) and related regulations by providing the advisers for certain hedge funds with gifts and gratuities in the form of below market office rents, personal loans with below market interest rates, event tickets, and other perks, in order to induce those hedge fund advisers to increase or retain their level of prime brokerage fees paid to UBS Securities. On November 22, 2010, UBS Securities entered into a Consent Order and Settlement with the Massachusetts Securities Division, pursuant to which UBS Securities agreed to implementing a disclosure policy and retaining an independent consultant to monitor the policy. UBS Securities also paid a $100,000 fine.

In the summer of 2008, the Massachusetts Securities Division, Texas State Securities Board, and the New York Attorney General (“NYAG”) all brought actions against UBS and UBS Financial Services, Inc. (“UBS Financial”), alleging violations of various state law anti-fraud provisions in connection with the marketing and sale of auction rate securities.

On August 8, 2008, UBS Securities and UBS Financial Services reached agreements with the SEC, the NYAG, the Massachusetts Securities Division and other state regulatory agencies represented by the North American Securities Administrators Association (“NASAA”) to restore liquidity to all remaining client’s holdings of auction rate securities by June 30, 2012. On October 2, 2008, UBS Securities and UBS Financial entered into a final consent agreement with the Massachusetts Securities Division settling all allegations in the Massachusetts Securities Division’s administrative proceeding against UBS Securities and UBS Financial with regards to the auction rate securities matter. On December 11, 2008, UBS Securities and UBS Financial executed an Assurance of Discontinuance in the auction rate securities settlement with the NYAG. On the same day, UBS Securities and UBS Financial finalized settlements with the SEC. UBS Securities and UBS Financial paid penalties of $75 million to NYAG and an additional $75 million to be apportioned among the participating NASAA states. In March 2010, UBS Securities and UBS Financial and NASAA agreed on final settlement terms, pursuant to which, UBS Securities and UBS Financial agreed to provide client liquidity up to an additional $200 million.

On August 14, 2008 the New Hampshire Bureau of Securities Regulation (the “Bureau”) filed an administrative action against UBS Securities relating to a student loan issuer, the New Hampshire Higher Education Loan Corp. (“NHHELCO”). The complaint alleged fraudulent and unethical conduct in violation of New Hampshire state statutes. On April 14, 2010, UBS entered into a Consent Order resolving all of the Bureau’s claims. UBS Securities paid $750,000 to the Bureau for all costs associated with the Bureau’s investigation. UBS Securities entered a separate civil settlement with NHHELCO and provided a total financial benefit of $20M to NHHELCO.

On April 29, 2010, the CFTC issued an order with respect to UBS Securities and levied a fine of $200,000. The Order stated that on February 6, 2009, UBS Securities’ employee broker aided and abetted UBS Securities’ customer’s concealment of material facts from the NYMEX in violation of Section 9(a)(4) of the CEA, 7 U.S.C. § 13(a)(4) (2006). Pursuant to NYMEX Rules, a block trade must be reported to NYMEX “within five minutes of the time of execution” consistent with the requirements of NYMEX Rule 6.21C(A)(6). Although the block trade in question was executed earlier in the day, UBS Securities’ employee broker aided and abetted its customer’s concealment of facts when, in response to the customer’s request to delay reporting the trade until after the close of trading, UBS Securities’ employee did not report the trade until after the close. Because the employee broker undertook his actions within the scope of his employment, pursuant to Section 2(a)(1)(B) of the CEA, 7 U.S.C. § 2(a)(1)(B) (2006), and Commission Regulation 1.2, 17 C.F.R. § 1.2 (2009), UBS Securities is liable for the employee broker’s aiding and abetting of its customer’s violation of Section 9(a)(4) of the CEA. The fine has been paid and the matter is now closed.

UBS Securities will act only as clearing broker for USNG and as such will be paid commissions for executing and clearing trades on behalf of USNG. UBS Securities has not passed upon the adequacy or accuracy of this annual report on Form 10-K. UBS Securities neither will act in any supervisory capacity with respect to USCF nor participate in the management of USCF or USNG.

UBS Securities is not affiliated with USNG or USCF. Therefore, USNG does not believe that USNG has any conflicts of interest with UBS Securities or their trading principals arising from their acting as USNG’s FCM.

Currently, USCF does not employ commodity trading advisors for the trading of USNG contracts. USCF currently does, however, employ a trading advisor for USCI, CPER, USAG and USMI, SummerHaven Investment Management, LLC (“SummerHaven”). If, in the future, USCF does employ commodity trading advisors for USNG, it will choose each advisor based on arm’s-length negotiations and will consider the advisor’s experience, fees and reputation.

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Fees are calculated on a daily basis (accrued at 1/365 of the applicable percentage of total net assets on that day) and paid on a monthly basis. Total net assets are calculated by taking the current market value of USNG’s total assets and subtracting any liabilities.

Fees and Compensation Arrangements between USNG and Non-Affiliated Service Providers ⁽³⁾

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Expenses Paid or Accrued by USNG through December 31, 2012 in dollar terms:

Expenses Paid or Accrued by USNG through December 31, 2012 as a Percentage of Average Daily Net Assets:

Other Fees. USNG also pays the fees and expenses associated with its tax accounting and reporting requirements. These fees were approximately $1,900,000 for the fiscal year ended December 31, 2012. In addition, USNG is responsible for paying its portion of the directors’ and officers’ liability insurance for USNG and the Related Public Funds and the fees and expenses of the independent directors who also serve as audit committee members of USNG and the Related Public Funds organized as limited partnerships and, as of July 8, 2011, those Related Public Funds organized as a series of a Delaware statutory trust. USNG shares the fees and expenses on a pro rata basis with each Related Public Fund, as described above, based on the relative assets of each fund computed on a daily basis. These fees and expenses for the year ended December 31, 2012 were $540,586 for USNG and the Related Public Funds. USNG’s portion of such fees and expenses for the year ended December 31, 2012 was $172,838.

Form of Units

Registered Form . Units are issued in registered form in accordance with the LP Agreement. The Administrator has been appointed registrar and transfer agent for the purpose of transferring units in certificated form. The Administrator keeps a record of all limited partners and holders of the units in certificated form in the registry (the “Register”). USCF recognizes transfers of units in certificated form only if done in accordance with the LP Agreement. The beneficial interests in such units are held in book-entry form through participants and/or accountholders in the Depository Trust Company (“DTC”).

Book Entry . Individual certificates are not issued for the units. Instead, units are represented by one or more global certificates, which are deposited by the Administrator with DTC and registered in the name of Cede & Co., as nominee for DTC. The global certificates evidence all of the units outstanding at any time. Unitholders are limited to: (1) participants in DTC such as banks, brokers, dealers and trust companies (“DTC Participants”), (2) those who maintain, either directly or indirectly, a custodial relationship with a DTC Participant (“Indirect Participants”), and (3) those banks, brokers, dealers, trust companies and others who hold interests in the units through DTC Participants or Indirect Participants, in each case who satisfy the requirements for transfers of units. DTC Participants acting on behalf of investors holding units through such participants’ accounts in DTC will follow the delivery practice applicable to securities eligible for DTC’s Same-Day Funds Settlement System. Units are credited to DTC Participants’ securities accounts following confirmation of receipt of payment.

DTC . DTC has advised USNG as follows: It is a limited purpose trust company organized under the laws of the State of New York and is a member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code and a “clearing agency” registered pursuant to the provisions of Section 17A of the Exchange Act. DTC holds securities for DTC Participants and facilitates the clearance and settlement of transactions between DTC Participants through electronic book-entry changes in accounts of DTC Participants.

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Calculating per unit NAV

USNG’s per unit NAV is calculated by:

The Administrator calculates the per unit NAV of USNG once each NYSE Arca trading day. The per unit NAV for a particular trading day is released after 4:00 p.m. New York time. Trading during the core trading session on the NYSE Arca typically closes at 4:00 p.m. New York time. The Administrator uses the NYMEX closing price (determined at the earlier of the close of the NYMEX or 2:30 p.m. New York time) for the Futures Contracts traded on the NYMEX, but calculates or determines the value of all other USNG investments (including Futures Contracts not traded on the NYMEX, Other Natural Gas-Related Investments and Treasuries) using market quotations, if available, or other information customarily used to determine the fair value of such investments as of the earlier of the close of the NYSE Arca or 4:00 p.m. New York time, in accordance with the current Administrative Agency Agreement among BBH&Co., USNG and USCF. “Other information” customarily used in determining fair value includes information consisting of market data in the relevant market supplied by one or more third parties including, without limitation, relevant rates, prices, yields, yield curves, volatilities, spreads, correlations or other market data in the relevant market; or information of the types described above from internal sources if that information is of the same type used by USNG in the regular course of its business for the valuation of similar transactions. The information may include costs of funding, to the extent costs of funding are not and would not be a component of the other information being utilized. Third parties supplying quotations or market data may include, without limitation, dealers in the relevant markets, end-users of the relevant product, information vendors, brokers and other sources of market information.

In addition, in order to provide updated information relating to USNG for use by investors and market professionals, the NYSE Arca calculates and disseminates throughout the core trading session on each trading day an updated indicative fund value. The indicative fund value is calculated by using the prior day’s closing per unit NAV of USNG as a base and updating that value throughout the trading day to reflect changes in the most recently reported trade price for the active natural gas Futures Contracts on the NYMEX. The prices reported for those Futures Contract months are adjusted based on the prior day’s spread differential between settlement values for the relevant contract and the spot month contract. In the event that the spot month contract is also the Benchmark Futures Contract, the last sale price for that contract is not adjusted. The indicative fund value unit basis disseminated during NYSE Arca core trading session hours should not be viewed as an actual real time update of the per unit NAV, because the per unit NAV is calculated only once at the end of each trading day based upon the relevant end of day values of USNG’s investments.

The indicative fund value is disseminated on a per unit basis every 15 seconds during regular NYSE Arca core trading session hours of 9:30 a.m. New York time to 4:00 p.m. New York time. The normal trading hours of the NYMEX are 10:00 a.m. New York time to 2:30 p.m. New York time. This means that there is a gap in time at the beginning and the end of each day during which USNG’s units are traded on the NYSE Arca, but real-time NYMEX trading prices for Futures Contracts traded on the NYMEX are not available. During such gaps in time, the indicative fund value will be calculated based on the end of day price of such Futures Contracts from the NYMEX’s immediately preceding trading session. In addition, other Futures Contracts, Other Natural Gas-Related Investments and Treasuries held by USNG will be valued by the Administrator, using rates and points received from client-approved third party vendors (such as Reuters and WM Company) and advisor quotes. These investments will not be included in the indicative fund value.

The NYSE Arca disseminates the indicative fund value through the facilities of CTA/CQ High Speed Lines. In addition, the indicative fund value is published on the NYSE Arca’s website and is available through on-line information services such as Bloomberg and Reuters.

Dissemination of the indicative fund value provides additional information that is not otherwise available to the public and is useful to investors and market professionals in connection with the trading of USNG units on the NYSE Arca. Investors and market professionals are able throughout the trading day to compare the market price of USNG and the indicative fund value. If the market price of USNG units diverges significantly from the indicative fund value, market professionals will have an incentive to execute arbitrage trades. For example, if USNG appears to be trading at a discount compared to the indicative fund value, a market professional could buy USNG units on the NYSE Arca and sell short Futures Contracts. Such arbitrage trades can tighten the tracking between the market price of USNG and the indicative fund value and thus can be beneficial to all market participants.

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Creation and Redemption of Units

USNG creates and redeems units from time to time, but only in one or more Creation Baskets or Redemption Baskets. The creation and redemption of baskets are only made in exchange for delivery to USNG or the distribution by USNG of the amount of Treasuries and any cash represented by the baskets being created or redeemed, the amount of which is based on the combined NAV of the number of units included in the baskets being created or redeemed determined after 4:00 p.m. New York time on the day the order to create or redeem baskets is properly received.

Authorized Purchasers are the only persons that may place orders to create and redeem baskets. Authorized Purchasers must be (1) registered broker-dealers or other securities market participants, such as banks and other financial institutions, that are not required to register as broker-dealers to engage in securities transactions as described below, and (2) DTC Participants. To become an Authorized Purchaser, a person must enter into an Authorized Purchaser Agreement with USCF on behalf of USNG. The Authorized Purchaser Agreement provides the procedures for the creation and redemption of baskets and for the delivery of the Treasuries and any cash required for such creations and redemptions. The Authorized Purchaser Agreement and the related procedures attached thereto may be amended by USNG, without the consent of any limited partner or unitholder or Authorized Purchaser. Authorized Purchasers will pay a transaction fee of $1,000 to USNG for each order they place to create or redeem one or more baskets. Authorized Purchasers who make deposits with USNG in exchange for baskets receive no fees, commissions or other form of compensation or inducement of any kind from either USNG or USCF, and no such person will have any obligation or responsibility to USCF or USNG to effect any sale or resale of units. As of December 31, 2012, 17 Authorized Purchasers had entered into agreements with USCF on behalf of USNG. During the year ended December 31, 2012, USNG issued 1,623 Creation Baskets and redeemed 1,343 Redemption Baskets.

Certain Authorized Purchasers are expected to be capable of participating directly in the physical natural gas market and the natural gas futures market. In some cases, Authorized Purchasers or their affiliates may from time to time buy natural gas or sell natural gas or Natural Gas Interests and may profit in these instances. USCF believes that the size and operation of the natural gas market make it unlikely that an Authorized Purchaser’s direct activities in the natural gas or securities markets will significantly affect the price of natural gas, Natural Gas Interests, or the price of the units.

Each Authorized Purchaser is required to be registered as a broker-dealer under the Exchange Act and is a member in good standing with FINRA, or exempt from being or otherwise not required to be registered as a broker-dealer or a member of FINRA, and qualified to act as a broker or dealer in the states or other jurisdictions where the nature of its business so requires. Certain Authorized Purchasers may also be regulated under federal and state banking laws and regulations. Each Authorized Purchaser has its own set of rules and procedures, internal controls and information barriers as it determines is appropriate in light of its own regulatory regime.

Under the Authorized Purchaser Agreement, USCF has agreed to indemnify the Authorized Purchasers against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the “Securities Act”), and to contribute to the payments the Authorized Purchasers may be required to make in respect of those liabilities.

The following description of the procedures for the creation and redemption of baskets is only a summary and an investor should refer to the relevant provisions of the LP Agreement and the form of Authorized Purchaser Agreement for more detail, each of which is incorporated by reference into this annual report on Form 10-K.

Creation Procedures

On any business day, an Authorized Purchaser may place an order with the Marketing Agent to create one or more baskets. For purposes of processing purchase and redemption orders, a “business day” means any day other than a day when any of the NYSE Arca, the NYMEX or the NYSE is closed for regular trading. Purchase orders must be placed by 12:00 p.m. New York time or the close of regular trading on the NYSE Arca, whichever is earlier. The day on which the Marketing Agent receives a valid purchase order is referred to as the purchase order date.

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By placing a purchase order, an Authorized Purchaser agrees to deposit Treasuries, cash, or a combination of Treasuries and cash, as described below. Prior to the delivery of baskets for a purchase order, the Authorized Purchaser must also have wired to the Custodian the non-refundable transaction fee due for the purchase order. Authorized Purchasers may not withdraw a creation request.

The manner by which creations are made is dictated by the terms of the Authorized Purchaser Agreement. By placing a purchase order, an Authorized Purchaser agrees to (1) deposit Treasuries, cash or a combination of Treasuries and cash with the Custodian, and (2) if required by USCF in its sole discretion, enter into or arrange for a block trade, an exchange for physical or exchange for swap, or any other over-the-counter energy transaction (through itself or a designated acceptable broker) with USNG for the purchase of a number and type of futures contracts at the closing settlement price for such contracts on the purchase order date. If an Authorized Purchaser fails to consummate (1) and (2), the order shall be cancelled. The number and type of contracts specified shall be determined by USCF, in its sole discretion, to meet USNG’s investment objective and shall be purchased as a result of the Authorized Purchaser’s purchase of units.

Determination of Required Deposits

The total deposit required to create each basket (“Creation Basket Deposit”) is the amount of Treasuries and/or cash that is in the same proportion to the total assets of USNG (net of estimated accrued but unpaid fees, expenses and other liabilities) on the purchase order date as the number of units to be created under the purchase order is in proportion to the total number of units outstanding on the purchase order dates. USCF determines, directly in its sole discretion or in consultation with the Administrator, the requirements for Treasuries and the amount of cash, including the maximum permitted remaining maturity of a Treasury and proportions of Treasury and cash that may be included in deposits to create baskets. The Marketing Agent will publish such requirements at the beginning of each business day. The amount of cash deposit required is the difference between the aggregate market value of the Treasuries required to be included in a Creation Basket Deposit as of 4:00 p.m. New York time on the date the order to purchase is properly received and the total required deposit.

Delivery of Required Deposits

An Authorized Purchaser who places a purchase order is responsible for transferring to USNG’s account with the Custodian the required amount of Treasuries and cash by the end of the third business day following the purchase order date. Upon receipt of the deposit amount, the Administrator directs DTC to credit the number of baskets ordered to the Authorized Purchaser’s DTC account on the third business day following the purchase order date. The expense and risk of delivery and ownership of Treasuries until such Treasuries have been received by the Custodian on behalf of USNG shall be borne solely by the Authorized Purchaser.

Because orders to purchase baskets must be placed by 12:00 p.m., New York time, but the total payment required to create a basket during the continuous offering period will not be determined until after 4:00 p.m. New York time on the date the purchase order is received, Authorized Purchasers will not know the total amount of the payment required to create a basket at the time they submit an irrevocable purchase order for the basket. USNG’s per unit NAV and the total amount of the payment required to create a basket could rise or fall substantially between the time an irrevocable purchase order is submitted and the time the amount of the purchase price in respect thereof is determined.

Rejection of Purchase Orders

USCF acting by itself or through the Marketing Agent shall have the absolute right but no obligation to reject a purchase order or a Creation Basket Deposit if:

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None of USCF, the Marketing Agent or the Custodian will be liable for the rejection of any purchase order or Creation Basket Deposit.

Redemption Procedures

The procedures by which an Authorized Purchaser can redeem one or more baskets mirror the procedures for the creation of baskets. On any business day, an Authorized Purchaser may place an order with the Marketing Agent to redeem one or more baskets. Redemption orders must be placed by 12:00 p.m. New York time or the close of regular trading on the NYSE Arca, whichever is earlier. A redemption order so received will be effective on the date it is received in satisfactory form by the Marketing Agent. The redemption procedures allow Authorized Purchasers to redeem baskets and do not entitle an individual unitholder to redeem any units in an amount less than a Redemption Basket, or to redeem baskets other than through an Authorized Purchaser.

By placing a redemption order, an Authorized Purchaser agrees to deliver the baskets to be redeemed through DTC’s book-entry system to USNG, as described below. Prior to the delivery of the redemption distribution for a redemption order, the Authorized Purchaser must also have wired to USNG’s account at the Custodian the non-refundable transaction fee due for the redemption order. An Authorized Purchaser may not withdraw a redemption order.

The manner by which redemptions are made is dictated by the terms of the Authorized Purchaser Agreement. By placing a redemption order, an Authorized Purchaser agrees to (1) deliver the Redemption Basket to be redeemed through DTC’s book-entry system to USNG’s account with the Custodian not later than 3:00 p.m. New York time on the third business day following the effective date of the redemption order (“Redemption Distribution Date”), and (2) if required by USCF in its sole discretion, enter into or arrange for a block trade, an exchange for physical or exchange for swap, or any other over-the-counter energy transaction (through itself or a designated acceptable broker) with USNG for the sale of a number and type of futures contracts at the closing settlement price for such contracts on the Redemption Order Date. If an Authorized Purchaser fails to consummate (1) and (2) above, the order shall be cancelled. The number and type of contracts specified shall be determined by USCF, in its sole discretion, to meet USNG’s investment objective and shall be sold as a result of the Authorized Purchaser’s sale of units.

Determination of Redemption Distribution

The redemption distribution from USNG consists of a transfer to the redeeming Authorized Purchaser of an amount of Treasuries and/or cash that is in the same proportion to the total assets of USNG (net of estimated accrued but unpaid fees, expenses and other liabilities) on the date the order to redeem is properly received as the number of units to be redeemed under the redemption order is in proportion to the total number of units outstanding on the date the order is received. USCF, directly or in consultation with the Administrator, determines the requirements for Treasuries and the amounts of cash, including the maximum permitted remaining maturity of a Treasury, and the proportions of Treasuries and cash that may be included in distributions to redeem baskets. The Marketing Agent will publish an estimate of the redemption distribution per basket as of the beginning of each business day.

Delivery of Redemption Distribution

The redemption distribution due from USNG will be delivered to the Authorized Purchaser by 3:00 p.m. New York time on the third business day following the redemption order date if, by 3:00 p.m. New York time on such third business day, USNG’s DTC account has been credited with the baskets to be redeemed. If USNG’s DTC account has not been credited with all of the baskets to be redeemed by such time, the redemption distribution will be delivered to the extent of whole baskets received. Any remainder of the redemption distribution will be delivered on the next business day to the extent of remaining whole baskets received if USNG receives the fee applicable to the extension of the redemption distribution date which USCF may, from time to time, determine and the remaining baskets to be redeemed are credited to USNG’s DTC account by 3:00 p.m. New York time on such next business day. Any further outstanding amount of the redemption order shall be cancelled. Pursuant to information from USCF, the Custodian will also be authorized to deliver the redemption distribution notwithstanding that the baskets to be redeemed are not credited to USNG’s DTC account by 3:00 p.m. New York time on the third business day following the redemption order date if the Authorized Purchaser has collateralized its obligation to deliver the baskets through DTC’s book entry-system on such terms as USCF may from time to time determine.

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Suspension or Rejection of Redemption Orders

USCF may, in its discretion, suspend the right of redemption, or postpone the redemption settlement date, (1) for any period during which the NYSE Arca or the NYMEX is closed other than customary weekend or holiday closings, or trading on the NYSE Arca or the NYMEX is suspended or restricted, (2) for any period during which an emergency exists as a result of which delivery, disposal or evaluation of Treasuries is not reasonably practicable, or (3) for such other period as USCF determines to be necessary for the protection of the limited partners or unitholders. For example, USCF may determine that it is necessary to suspend redemptions to allow for the orderly liquidation of USNG’s assets at an appropriate value to fund a redemption. If USCF has difficulty liquidating its positions, e.g. , because of a market disruption event in the futures markets, a suspension of trading by the exchange where the futures contracts are listed or an unanticipated delay in the liquidation of a position in an over-the-counter contract, it may be appropriate to suspend redemptions until such time as such circumstances are rectified. None of USCF, the Marketing Agent, the Administrator, or the Custodian will be liable to any person or in any way for any loss or damages that may result from any such suspension or postponement.

Redemption orders must be made in whole baskets. USCF will reject a redemption order if the order is not in proper form as described in the Authorized Purchaser Agreement or if the fulfillment of the order, in the opinion of its counsel, might be unlawful. USCF may also reject a redemption order if the number of units being redeemed would reduce the remaining outstanding units to 100,000 units ( i.e. , one basket) or less.

Creation and Redemption Transaction Fee

To compensate USNG for its expenses in connection with the creation and redemption of baskets, an Authorized Purchaser is required to pay a transaction fee to USNG of $1,000 per order to create or redeem baskets, regardless of the number of baskets in such order. An order may include multiple baskets. The transaction fee may be reduced, increased or otherwise changed by USCF. USCF shall notify DTC of any change in the transaction fee and will not implement any increase in the fee for the redemption of baskets until 30 days after the date of the notice.

Tax Responsibility

Authorized Purchasers are responsible for any transfer tax, sales or use tax, stamp tax, recording tax, value added tax or similar tax or governmental charge applicable to the creation or redemption of baskets, regardless of whether or not such tax or charge is imposed directly on the Authorized Purchaser, and agree to indemnify USCF and USNG if they are required by law to pay any such tax, together with any applicable penalties, additions to tax and interest thereon.

Secondary Market Transactions

As noted, USNG creates and redeems units from time to time, but only in one or more Creation Baskets or Redemption Baskets. The creation and redemption of baskets are only made in exchange for delivery to USNG or the distribution by USNG of the amount of Treasuries and cash represented by the baskets being created or redeemed, the amount of which will be based on the aggregate NAV of the number of units included in the baskets being created or redeemed determined on the day the order to create or redeem baskets is properly received.

As discussed above, Authorized Purchasers are the only persons that may place orders to create and redeem baskets. Authorized Purchasers must be registered broker-dealers or other securities market participants, such as banks and other financial institutions that are not required to register as broker-dealers to engage in securities transactions. An Authorized Purchaser is under no obligation to create or redeem baskets, and an Authorized Purchaser is under no obligation to offer to the public units of any baskets it does create. Authorized Purchasers that do offer to the public units from the baskets they create will do so at per-unit offering prices that are expected to reflect, among other factors, the trading price of the units on the NYSE Arca, the NAV of USNG at the time the Authorized Purchaser purchased the Creation Baskets and the per unit NAV of the units at the time of the offer of the units to the public, the supply of and demand for units at the time of sale, and the liquidity of the Futures Contract market and the market for Other Natural Gas-Related Investments. The prices of units offered by Authorized Purchasers are expected to fall between USNG’s per unit NAV and the trading price of the units on the NYSE Arca at the time of sale. Units initially comprising the same basket but offered by Authorized Purchasers to the public at different times may have different offering prices. An order for one or more baskets may be placed by an Authorized Purchaser on behalf of multiple clients. Authorized Purchasers who make deposits with USNG in exchange for baskets receive no fees, commissions or other form of compensation or inducement of any kind from either USNG or USCF, and no such person has any obligation or responsibility to USCF or USNG to effect any sale or resale of units. Units trade in the secondary market on the NYSE Arca. Units may trade in the secondary market at prices that are lower or higher relative to their per unit NAV. The amount of the discount or premium in the trading price relative to the per unit NAV may be influenced by various factors, including the number of investors who seek to purchase or sell units in the secondary market and the liquidity of the Futures Contracts market and the market for Other Natural Gas-Related Investments. While the units trade during the core trading session on the NYSE Arca until 4:00 p.m. New York time, liquidity in the market for Futures Contracts and Other Natural Gas-Related Investments may be reduced after the close of the NYMEX at 2:30 p.m. New York time. As a result, during this time, trading spreads, and the resulting premium or discount, on the units may widen.

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Investments

USCF causes USNG to transfer the proceeds from the sale of Creation Baskets to the Custodian or other custodian for trading activities. USCF will invest USNG’s assets in Futures Contracts and Other Natural Gas-Related Investments and investments in Treasuries, cash and/or cash equivalents. When USNG purchases a Futures Contract and certain exchange-traded Other Natural Gas-Related Investments, USNG is required to deposit 5% to 30% with the selling FCM on behalf of the exchange a portion of the value of the contract or other interest as security to ensure payment for the obligation under Natural Gas Interests at maturity. This deposit is known as initial margin. Counterparties in transactions in over-the-counter Natural Gas Interests will generally impose similar collateral requirements on USNG. USCF will invest the assets that remain after margin and collateral are posted in Treasuries, cash and/or cash equivalents subject to these margin and collateral requirements. USCF has sole authority to determine the percentage of assets that are:

Ongoing margin and collateral payments will generally be required for both exchange-traded and over-the-counter Natural Gas Interests based on changes in the value of the Natural Gas Interests. Furthermore, ongoing collateral requirements with respect to over-the-counter Natural Gas Interests are negotiated by the parties, and may be affected by overall market volatility, volatility of the underlying commodity or index, the ability of the counterparty to hedge its exposure under a Natural Gas Interest and each party’s creditworthiness. In light of the differing requirements for initial payments under exchange-traded and over-the-counter Natural Gas Interests and the fluctuating nature of ongoing margin and collateral payments, it is not possible to estimate what portion of USNG’s assets will be posted as margin or collateral at any given time. The Treasuries, cash and cash equivalents held by USNG will constitute reserves that will be available to meet ongoing margin and collateral requirements. All interest income will be used for USNG’s benefit.

A FCM, counterparty, government agency or commodity exchange could increase margin or collateral requirements applicable to USNG to hold trading positions at any time. Moreover, margin is merely a security deposit and has no bearing on the profit or loss potential for any positions held.

The assets of USNG posted as margin for Futures Contracts are held in segregated accounts pursuant to the CEA and CFTC regulations.

USNG must post both collateral and independent amounts to its swap counterparties. The amount of collateral USNG posts changes according to the amounts owed by USNG to its counterparty on a given swap transaction, while independent amounts are fixed amounts posted by USNG at the start of a swap transaction. Collateral and independent amounts posted to swap counterparties are held by a third party custodian.

The Commodity Interest Markets

General

The CEA governs the regulation of commodity interest transactions, markets and intermediaries. The CEA provides for varying degrees of regulation of commodity interest transactions depending upon: (1) the type of instrument being traded ( e.g ., contracts for future delivery, options, swaps or spot contracts), (2) the type of commodity underlying the instrument (distinctions are made between instruments based on agricultural commodities, energy and metals commodities and financial commodities), (3) the nature of the parties to the transaction (retail, eligible contract participant, or eligible commercial entity), (4) whether the transaction is entered into on a principal-to-principal or intermediated basis, (5) the type of market on which the transaction occurs, and (6) whether the transaction is subject to clearing through a clearing organization.

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The offer and sale of units of USNG, as well as units of each of the Related Public Funds, is registered under the Securities Act. USNG and the Related Public Funds are subject to the requirements of the Securities Act, the Exchange Act and the rules and regulations adopted thereunder, as administered by the Securities and Exchange Commission (the “SEC”). Firms’ participation in the distribution of units are regulated as described above, as well as by the self regulatory association, FINRA.

Futures Contracts

A futures contract is a standardized contract traded on, or subject to the rules of, an exchange that calls for the future delivery of a specified quantity and type of a commodity at a specified time and place. Futures contracts are traded on a wide variety of commodities, including agricultural products, bonds, stock indices, interest rates, currencies, energy and metals. The size and terms of futures contracts on a particular commodity are identical and are not subject to any negotiation, other than with respect to price and the number of contracts traded between the buyer and seller.

The contractual obligations of a buyer or seller may generally be satisfied by taking or making physical delivery of the underlying commodity or by making an offsetting sale or purchase of an identical futures contract on the same or linked exchange before the designated date of delivery. The difference between the price at which the futures contract is purchased or sold and the price paid for the offsetting sale or purchase, after allowance for brokerage commissions, constitutes the profit or loss to the trader. Some futures contracts, such as stock index contracts, settle in cash (reflecting the difference between the contract purchase/sale price and the contract settlement price) rather than by delivery of the underlying commodity.

In market terminology, a trader who purchases a futures contract is long in the market and a trader who sells a futures contract is short in the market. Before a trader closes out his long or short position by an offsetting sale or purchase, his outstanding contracts are known as open trades or open positions. The aggregate amount of open positions held by traders in a particular contract is referred to as the open interest in such contract.

Forward Contracts

A forward contract is a contractual obligation to purchase or sell a specified quantity of a commodity at or before a specified date in the future at a specified price and, therefore, is economically similar to a futures contract. Unlike futures contracts, however, forward contracts are typically traded in the over-the-counter markets and are not standardized contracts. Forward contracts for a given commodity are generally available for various amounts and maturities and are subject to individual negotiation between the parties involved. Moreover, generally there is no direct means of offsetting or closing out a forward contract by taking an offsetting position as one would a futures contract on a U.S. exchange. If a trader desires to close out a forward contract position, he generally will establish an opposite position in the contract but will settle and recognize the profit or loss on both positions simultaneously on the delivery date. Thus, unlike in the futures contract market where a trader who has offset positions will recognize profit or loss immediately, in the forward market a trader with a position that has been offset at a profit will generally not receive such profit until the delivery date, and likewise a trader with a position that has been offset at a loss will generally not have to pay money until the delivery date. In recent years, however, the terms of forward contracts have become more standardized, and in some instances such contracts now provide a right of offset or cash settlement as an alternative to making or taking delivery of the underlying commodity.

In general, the CFTC does not regulate the interbank and forward foreign currency markets with respect to transactions in contracts between certain sophisticated counterparties such as USNG or between certain regulated institutions and retail investors. Although U.S. banks are regulated in various ways by the Federal Reserve Board, the Comptroller of the Currency and other U.S. federal and state banking officials, banking authorities do not regulate the forward markets to the same extent that the swap markets will be regulated by the CFTC once the Dodd-Frank Act is fully implemented. At a minimum, over-the-counter currency forwards, options and swaps will be subject to heightened recordkeeping, reporting and business conduct standards.

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On November 16, 2012, the Secretary of the Treasury issued a final determination that exempts both foreign exchange swaps and foreign exchange forwards from the definition of “swap” and, by extension, additional regulatory requirements (such as clearing and margin). The final determination does not extend to other foreign exchange derivatives, such as foreign exchange options, currency swaps and non-deliverable forwards.

While the U.S. government does not currently impose any restrictions on the movements of currencies, it could choose to do so. The imposition or relaxation of exchange controls in various jurisdictions could significantly affect the market for that and other jurisdictions’ currencies. Trading in the interbank market also exposes USNG to a risk of default since the failure of a bank with which USNG had entered into a forward contract would likely result in a default and thus possibly substantial losses to USNG.

Options on Futures Contracts

Options on futures contracts are standardized contracts traded on an exchange. An option on a futures contract gives the buyer of the option the right, but not the obligation, to take a position at a specified price (the striking, strike, or exercise price) in the underlying futures contract or underlying interest. The buyer of a call option acquires the right, but not the obligation, to purchase or take a long position in the underlying interest, and the buyer of a put option acquires the right, but not the obligation, to sell or take a short position in the underlying interest.

The seller, or writer, of an option is obligated to take a position in the underlying interest at a specified price opposite to the option buyer if the option is exercised. The seller of a call option must stand ready to take a short position in the underlying interest at the strike price if the buyer should exercise the option. The seller of a put option, on the other hand, must stand ready to take a long position in the underlying interest at the strike price.

A call option is said to be in-the-money if the strike price is below current market levels and out-of-the-money if the strike price is above current market levels. Conversely, a put option is said to be in-the-money if the strike price is above the current market levels and out-of-the-money if the strike price is below current market levels.

Options have limited life spans, usually tied to the delivery or settlement date of the underlying interest. Some options, however, expire significantly in advance of such date. The purchase price of an option is referred to as its premium, which consists of its intrinsic value (which is related to the underlying market value) plus its time value. As an option nears its expiration date, the time value shrinks and the market and intrinsic values move into parity. An option that is out-of-the-money and not offset by the time it expires becomes worthless. On certain exchanges, in-the-money options are automatically exercised on their expiration date, but on others unexercised options simply become worthless after their expiration date.

Regardless of how much the market swings, the most an option buyer can lose is the option premium. The option buyer deposits his premium with his broker, and the money goes to the option seller. Option sellers, on the other hand, face risks similar to participants in the futures markets. For example, since the seller of a call option is assigned a short futures position if the option is exercised, his risk is the same as someone who initially sold a futures contract. Because no one can predict exactly how the market will move, the option seller posts margin to demonstrate his ability to meet any potential contractual obligations.

Options on Forward Contracts or Commodities

Options on forward contracts or commodities operate in a manner similar to options on futures contracts. An option on a forward contract or commodity gives the buyer of the option the right, but not the obligation, to take a position at a specified price in the underlying forward contract or commodity. However, unlike options on futures contracts, options on forward contracts or on commodities are individually negotiated contracts between counterparties and are typically traded in the over-the-counter market. Therefore, options on forward contracts and physical commodities possess many of the same characteristics of forward contracts with respect to offsetting positions and credit risk that are described above.

Swap Contracts

Swap transactions generally involve contracts between two parties to exchange a stream of payments computed by reference to a notional amount and the price of the asset that is the subject of the swap. Swap contracts are principally traded off-exchange, although certain swap contracts are also being traded in electronic trading facilities and cleared through clearing organizations.

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Swaps are usually entered into on a net basis, that is, the two payment streams are netted out in a cash settlement on the payment date or dates specified in the agreement, with the parties receiving or paying, as the case may be, only the net amount of the two payments. Swaps do not generally involve the delivery of underlying assets or principal. Accordingly, the risk of loss with respect to swaps is generally limited to the net amount of payments that the party is contractually obligated to make. In some swap transactions one or both parties may require collateral deposits from the counterparty to support that counterparty’s obligation under the swap agreement. If the counterparty to such a swap defaults, the risk of loss consists of the net amount of payments that the party is contractually entitled to receive less any collateral deposits it is holding.

Some swap transactions are cleared through central counterparties. These transactions, known as cleared swaps, involve two counterparties first agreeing to the terms of a swap transaction, then submitting the transaction to a clearing house that acts as the central counterparty. Once accepted by the clearing house, the original swap transaction is novated and the central counterparty becomes the counterparty to a trade with each of the original parties based upon the trade terms determined in the original transaction. In this manner each individual swap counterparty reduces its risk of loss due to counterparty nonperformance because the clearing house acts as the counterparty to each transaction.

“Swap” Transactions

The Dodd-Frank Act imposes new regulatory requirements on certain “swap” transactions that USNG is authorized to engage in that may ultimately impact the ability of USNG to meet its investment objective. On August 13, 2012, the CFTC and the SEC published joint final rules defining the terms “swap” and “security-based swaps.” The term “swap” is broadly defined to include various types of over-the-counter derivatives, including swaps and options. The effective date of these final rules was October 12, 2012.

The Dodd-Frank Act requires that certain transactions ultimately falling within the definition of “swap” be executed on organized exchanges or “swap execution facilities” and cleared through regulated clearing organizations (which are referred to in the Dodd-Frank Act as “derivative clearing organizations” (“DCOs”)), if the CFTC mandates the central clearing of a particular contract. On November 28, 2012, the CFTC issued its final clearing determination requiring that certain credit default swaps and interest rate swaps be cleared by registered DCOs. This is the CFTC’s first clearing determination under the Dodd-Frank Act and became effective on February 11, 2013. Determination on other types of swaps are expected in the future, and, when finalized, could require USNG to centrally clear certain over-the-counter instruments presently entered into and settled on a bi-lateral basis. If a swap is required to be cleared, the initial margin will be set by the clearing organizations, subject to certain regulatory requirements and guidelines. Initial and variation margin requirements for swap dealers and major swap participants who enter into uncleared swaps and capital requirements for swap dealers and major swap participants who enter into both cleared and uncleared trades will be set by the CFTC, the SEC or the applicable “Prudential Regulator.” On May 23, 2012, the CFTC published final regulations, which became effective as of July 23, 2012, to determine which entities will be regulated as “swap dealers” and “major swap participants” and thus have to comply with these capital and margin requirements (as well as a multitude of other requirements under the Dodd-Frank Act). Most of the requirements became effective on October 12, 2012 when additional final rules defining the terms “swap,” “security-based swap” and “mixed swap” became effective. However, on October 11, 2012 and October 12, 2012, the CFTC issued several no-action letters and interpretative guidance which delayed much of the implementation of these requirements from October 12, 2012 until December 31, 2012. Increased regulation of, and the imposition of additional costs on, swap transactions could have an adverse effect on USNG by, for example, reducing the size of and therefore liquidity in the derivatives market, increasing transaction costs and decreasing the ability to customize derivative transactions.

On February 7, 2012, the CFTC published a rule requiring each FCM and DCO to segregate cleared swaps and related collateral posted by a customer of the FCM from the assets of the FCM or DCO, although such property can be commingled with the property of other cleared swaps customers of the FCM or DCO. This rule addresses losses incurred by a DCO in a so-called “double default” scenario in which a customer of a FCM defaults in its obligations to the FCM and the FCM, in turn, defaults in its obligations to the DCO. Under this scenario, the DCO can only access the collateral attributable to other customers of the DCO whose cleared swap positions are in a loss position following the primary customer’s default. This rule became effective on November 8, 2012. Some market participants have expressed concern that the requirements of this segregation rule may result in higher initial margins or higher fees. USNG does not anticipate any impact to its operations in order to meet the requirements of the new rule.

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Additionally, the CFTC published rules on February 17, 2012 and April 3, 2012 that require “swap dealers” and “major swap participants” to: 1) adhere to business conduct standards, 2) implement policies and procedures to ensure compliance with the CEA and 3) maintain records of such compliance. These new requirements may impact the documentation requirements for both cleared and non-cleared swaps and cause swap dealers and major swap participants to face increased compliance costs that, in turn, may be passed along to counterparties (such as USNG) in the form of higher fees and expenses related to trading swaps.

On February 24, 2012, the CFTC amended certain disclosure obligations to require that the operator of a commodity pool that invests in swaps include standardized swap risk disclosures in the pool’s disclosure documents by December 31, 2012.

On December 5, 2012, the CFTC’s Division of Market Oversight issued a letter providing swap dealers with time-limited no-action relief from swap data reporting obligations with respect to equity swaps, foreign exchange swaps and other commodity swaps. For these asset classes, the letter provides swap dealers with reporting relief (i) with respect to real-time price reporting and regular swap reporting (under Part 43 and Part 45 of the CFTC’s regulations, respectively), until February 28, 2013, and (ii) historical swap reporting requirements (under Part 46 of the CFTC’s regulations) until March 30, 2013.

On December 21, 2012, the CFTC’s Division of Market Oversight issued two letters providing certain swap dealers with time-limited no-action relief from some swap data reporting obligations. One letter provides relief from reporting requirements for branches of swap dealers located in emerging markets who encounter technical difficulties in complying with the reporting rules. The letter also provides that swap dealers may delay reporting compliance for certain complex and exotic swaps until April 30, 2012.

Under a second letter, all swap dealers have until April 10, 2013 to report certain information about their counterparties, including: status as a major swap participant, a financial entity, a U.S. person or a commercial end-user.

On December 18, 2012, the CFTC deferred the compliance date for many of the Dodd-Frank Act’s external business conduct standards from December 31, 2012 to May 1, 2013, and for some requirements to July 1, 2013, providing swap dealers an additional four to six months from the original compliance date.

Regulation

Futures exchanges in the United States are subject to varying degrees of regulation under the CEA depending on whether such exchange is a designated contract market, exempt board of trade or electronic trading facility. Clearing organizations are also subject to the CEA and the rules and regulations adopted thereunder and administered by the CFTC. The CFTC is the governmental agency charged with responsibility for regulation of futures exchanges and commodity interest trading conducted on those exchanges. The CFTC’s function is to implement the CEA’s objectives of preventing price manipulation and excessive speculation and promoting orderly and efficient commodity interest markets. In addition, the various exchanges and clearing organizations themselves exercise regulatory and supervisory authority over their member firms.

The CFTC also regulates the activities of “commodity trading advisors” and “commodity pool operators” and the CFTC has adopted regulations with respect to certain of such persons’ activities. Pursuant to its authority, the CFTC requires a CPO, such as USCF, to keep accurate, current and orderly records with respect to each pool it operates. The CFTC may suspend, modify or terminate the registration of any registrant for failure to comply with CFTC rules or regulations. Suspension, restriction or termination of USCF’s registration as a CPO would prevent it, until such time (if any) as such registration were to be reinstated, from managing, and might result in the termination of, USNG or the Related Public Funds.

The CEA also gives the states certain powers to enforce its provisions and the regulations of the CFTC.

Under certain circumstances, the CEA grants unitholders the right to institute a reparations proceeding before the CFTC against USCF (as a registered commodity pool operator), as well as those of their respective employees who are required to be registered under the CEA. Unitholders may also be able to maintain a private right of action for certain violations of the CEA.

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Pursuant to authority in the CEA, the NFA has been formed and registered with the CFTC as a registered futures association. The NFA is the only self regulatory association for commodities professionals other than the exchanges. As such, the NFA promulgates rules governing the conduct of commodity professionals and disciplines those professionals that do not comply with such standards. The CFTC has delegated to the NFA responsibility for the registration of commodity pool operation. USCF is a member of the NFA. As a member of the NFA, USCF is subject to NFA standards relating to fair trade practices, financial condition and consumer protection. The CFTC is prohibited by statute from regulating trading on foreign commodity exchanges and markets.

The CEA requires all FCMs, such as USNG’s clearing brokers, to meet and maintain specified fitness and financial requirements, to segregate customer funds from proprietary funds and account separately for all customers’ funds and positions, and to maintain specified books and records open to inspection by the staff of the CFTC. The CFTC has similar authority over introducing brokers, or persons who solicit or accept orders for commodity interest trades but who do not accept margin deposits for the execution of trades. The CEA authorizes the CFTC to regulate trading by FCMs and by their officers and directors, permits the CFTC to require action by exchanges in the event of market emergencies, and establishes an administrative procedure under which customers may institute complaints for damages arising from alleged violations of the CEA. The CEA also gives the states powers to enforce its provisions and the regulations of the CFTC.

The regulations of the CFTC and the NFA prohibit any representation by a person registered with the CFTC or by any member of the NFA, that registration with the CFTC, or membership in the NFA, in any respect indicates that the CFTC or the NFA, as the case may be, has approved or endorsed that person or that person’s trading program or objectives. The registrations and memberships of the parties described in this summary must not be considered as constituting any such approval or endorsement. Likewise, no futures exchange has given or will give any similar approval or endorsement.

On November 14, 2012, the CFTC proposed new regulations that would require enhanced customer protections, risk management programs, internal monitoring and controls, capital and liquidity standards, customer disclosures and auditing and examination programs for FCMs. The proposed rules are intended to afford greater assurances to market participants that customer segregated funds and secured amounts are protected, customers are provided with appropriate notice of the risks of futures trading and of the FCMs with which they may choose to do business, FCMs are monitoring and managing risks in a robust manner, the capital and liquidity of FCMs are strengthened to safeguard the continued operations and the auditing and examination programs of the CFTC and the self-regulatory organizations are monitoring the activities of FCMs in a thorough manner. The final regulations have not yet been adopted.

USNG’s investors are afforded prescribed rights for reparations under the CEA against USCF (as a registered commodity pool operator), as well as its respective employees who are required to be registered under the CEA. Investors may also be able to maintain a private right of action for violations of the CEA. The CFTC has adopted rules implementing the reparation provisions of the CEA, which provide that any person may file a complaint for a reparations award with the CFTC for violation of the CEA against a floor broker or a FCM, introducing broker, commodity trading advisor, CPO and their respective associated persons.

The regulation of commodity interest trading in the United States and other countries is an evolving area of the law, as exemplified by the various discussions of the Dodd-Frank Act. The various statements made in this summary are subject to modification by legislative action and changes in the rules and regulations of the CFTC, the NFA, the futures exchanges, clearing organizations and other regulatory bodies.

Futures Contracts and Position Limits

The CFTC is prohibited by statute from regulating trading on non-U.S. futures exchanges and markets. The CFTC, however, has adopted regulations relating to the marketing of non-U.S. futures contracts in the United States. These regulations permit certain contracts traded on non-U.S. exchanges to be offered and sold in the United States.

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In October 2011, the CFTC finalized the Position Limit Rules, which were scheduled to become effective on October 12, 2012. However, on September 28, 2012, the United States District Court for the District of Columbia vacated these regulations on the basis of ambiguities in the provisions of the CEA (as modified by the Dodd-Frank Act) upon which the regulations were based. In its September 28, 2012, the court remanded the Position Limit Rules to the CFTC with instructions to use its expertise and experience to resolve the ambiguities in the statute. On November 15, 2012, the CFTC indicated that it will move forward with an appeal of the District Court’s decision to vacate the Position Limit Rules. At this time, it is not possible to predict how the CFTC’s appeal could affect USNG, but it may be substantial and adverse. Furthermore, until such time as the appeal is resolved or, if applicable revisions to the Position Limit Rules are proposed and adopted, the regulatory architecture in effect prior to the enactment of the Position Limit Rules will govern transactions in commodities and related derivatives. As a result, USNG may be limited with respect to the size of its investments in any commodities subject to these limits. Finally, subject to certain narrow exceptions, the vacated Position Limit Rules would have required the aggregation, for purposes of the position limits, of all positions in the 28 Referenced Contracts held by a single entity and its affiliates, regardless of whether such position existed on U.S. futures exchanges, non-U.S. futures exchanges, in cleared swaps or in over-the-counter swaps. The CFTC is presently considering new aggregation rules, under a rulemaking proposal that is distinct from the Position Limit Rules. At this time, it is unclear how any modified aggregation rules may affect USNG, but it may be substantial and adverse. By way of example, the aggregation rules in combination with any potential revised Position Limit Rules may negatively impact the ability of USNG to meet its investment objectives through limits that may inhibit USCF’s ability to sell additional Creation Baskets of USNG.

Based on its current understanding of the final position limit regulations, USCF does not anticipate significant negative impact on the ability of USNG to achieve its investment objective.

Commodity Margin

Original or initial margin is the minimum amount of funds that must be deposited by a commodity interest trader with the trader’s broker to initiate and maintain an open position in futures contracts. Maintenance margin is the amount (generally less than the original margin) to which a trader’s account may decline before he must deliver additional margin. A margin deposit is like a cash performance bond. It helps assure the trader’s performance of the futures contracts that he or she purchases or sells. Futures contracts are customarily bought and sold on initial margin that represents a very small percentage (ranging upward from less than 5%) of the aggregate purchase or sales price of the contract. Because of such low margin requirements, price fluctuations occurring in the futures markets may create profits and losses that, in relation to the amount invested, are greater than are customary in other forms of investment or speculation. As discussed below, adverse price changes in the futures contract may result in margin requirements that greatly exceed the initial margin. In addition, the amount of margin required in connection with a particular futures contract is set from time to time by the exchange on which the contract is traded and may be modified from time to time by the exchange during the term of the contract.

Brokerage firms, such as USNG’s clearing brokers, carrying accounts for traders in commodity interest contracts may not accept lower, and generally require higher, amounts of margin as a matter of policy to further protect themselves. The clearing brokers require USNG to make margin deposits equal to exchange minimum levels for all commodity interest contracts. This requirement may be altered from time to time in the clearing brokers’ discretion.

Regulators have not yet finalized the Dodd-Frank Act rules regarding initial margin levels for over-the-counter derivatives. It is possible that such levels may be higher than those for futures contracts. Also, initial margin requirements for non-cleared swaps that will be subject to higher margin requirements than cleared swaps. And, under pending rule proposals, USNG may be required to post, but not be entitled to receive, initial and variation margin in respect of non-cleared swaps. Until such time as the regulators finalize these margin rules, trading in the over-the-counter markets where no clearing facility is provided generally will not require margin per se. Rather, it will involve the extension of credit between counterparties that is secured by transfers of credit support and/or independent amounts. Credit support is transferred between counterparties in respect of the open over-the-counter derivatives entered into between them, while independent amounts are fixed amounts posted by one or both counterparties at the execution of a particular over-the-counter transaction.

When a trader purchases an option, there is no margin requirement; however, the option premium must be paid in full. When a trader sells an option, on the other hand, he or she is required to deposit margin in an amount determined by the margin requirements established for the underlying interest and, in addition, an amount substantially equal to the current premium for the option. The margin requirements imposed on the selling of options, although adjusted to reflect the probability that out-of-the-money options will not be exercised, can in fact be higher than those imposed in dealing in the futures markets directly. Complicated margin requirements apply to spreads and conversions, which are complex trading strategies in which a trader acquires a mixture of options positions and positions in the underlying interest.

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Margin requirements are computed each day by a trader’s clearing broker. When the market value of a particular open commodity interest position changes to a point where the margin on deposit does not satisfy maintenance margin requirements, a margin call is made by the broker. If the margin call is not met within a reasonable time, the broker may close out the trader’s position. With respect to USNG’s trading, USNG (and not its investors personally) is subject to margin calls.

Finally, many major U.S. exchanges have passed certain cross margining arrangements involving procedures pursuant to which the futures and options positions held in an account would, in the case of some accounts, be aggregated and margin requirements would be assessed on a portfolio basis, measuring the total risk of the combined positions.

SEC Reports

USNG makes available, free of charge, on its website, its annual reports on Form 10-K, its quarterly reports on Form 10-Q, its current reports on Form 8-K and amendments to these reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after these forms are filed with, or furnished to, the SEC. These reports are also available from the SEC though its website at: www.sec.gov.

CFTC Reports

USNG also makes available its monthly reports and its annual reports required to be prepared and filed with the NFA under the CFTC regulations.

Intellectual Property

USCF owns trademark registrations for UNITED STATES NATURAL GAS FUND (U.S. Reg. No. 3407494) for “fund investment services in the field of natural gas futures contracts, cash-settled options on natural gas futures contracts, forward contracts for natural gas, over-the-counter transactions based on the price of natural gas, and indices based on the foregoing,” in use since April 18, 2007, UNG UNITED STATES NATURAL GAS FUND, LP (and Flame Design) (U.S. Reg. No. 3683574) for “fund investment services in the field of natural gas futures contracts, cash-settled options on natural gas futures contracts, forward contracts for natural gas, over-the-counter transactions based on the price of natural gas, and indices based on the foregoing,” in use since April 18, 2007 and UNG UNITED STATES NATURAL GAS FUND, LP (and Flame Design), S.N. 85592277 in use since September 4, 2012. USNG relies upon these trademarks through which it markets its services and strives to build and maintain brand recognition in the market and among current and potential investors. So long as USNG continues to use these trademarks to identify its services, without challenge from any third party, and properly maintains and renews the trademark registrations under applicable laws, rules and regulations, it will continue to have indefinite protection for these trademarks under current laws, rules and regulations. USCF has been granted two patents Nos. 7,739,186 and 8,019,675, for systems and methods for an exchange-traded fund (ETF) that tracks the price of one or more commodities.