DBO Invesco DB Oil Fund

SUMMARY

This summary of all material information provided in this Prospectus is intended for quick reference only. For ease of reference, any references throughout this Prospectus to various actions taken by each of the Funds or each of the Master Funds are actually actions that the Trust or the Master Trust has taken on behalf of such respective Funds or Master Funds. The remainder of this Prospectus contains more detailed information. You should read the entire Prospectus, including all exhibits to the Prospectus, the information incorporated by reference in this Prospectus, including the financial statements and the notes to those financial statements in the Annual Report on Form 10-K and the Quarterly Report on Form 10-Q with respect to each Fund, before deciding to invest in Shares of any Fund. This Prospectus is intended to be used beginning July 14, 2008.

The Trust and the Funds; The Master Trust and the Master Funds

Each of the Trust and Master Trust was organized in seven separate series as a Delaware statutory trust rather than as seven separate statutory trusts in order to achieve certain administrative efficiencies. The interests of investors are not adversely affected by the choice of form of organization.

Shares Listed on the Amex

The Shares of each Fund are listed on the Amex under the following symbols:

Secondary market purchases and sales of Shares will be subject to ordinary brokerage commissions and charges.

Purchases and Sales in the Secondary Market on the Amex

The Shares of each Fund trade on the Amex like any other equity security.

Baskets of Shares in each Fund may be created or redeemed only by Authorized Participants. It is expected that Baskets in a Fund will be created when there is sufficient demand for Shares in such Fund that the market price per Share is at a premium to the net asset value per Share. Authorized Participants are expected to sell such Shares, which are listed on the Amex, to the public at prices that are expected to reflect, among other factors, the trading price of the Shares of such Fund on the Amex and the supply of and demand for Shares at the time of sale and are expected to fall between net asset value and the trading price of the Shares on the Amex at the time of sale. Similarly, it is expected that Baskets in a Fund will be redeemed when the market price per Share of such Fund is at a discount to the net asset value per Share. Retail investors seeking to purchase or sell Shares on any day are expected to effect

such transactions in the secondary market, on the Amex, at the market price per Share, rather than in connection with the creation or redemption of Baskets.

The market price of the Shares of a Fund may not be identical to the net asset value per Share, but these valuations are expected to be very close. Investors are able to use the indicative intra-day value per Share to determine if they want to purchase in the secondary market via the Amex. The intra-day indicative value per Share of each Fund is based on the prior day’s final net asset value, adjusted four times per minute throughout the day to reflect the continuous price changes of the Master Fund’s futures positions to provide a continuously updated estimated net asset value per Share.

Retail investors may purchase and sell Shares through traditional brokerage accounts. Purchases or sales of Shares may be subject to customary brokerage commissions. Investors are encouraged to review the terms of their brokerage accounts for applicable charges.

Pricing Information Available on the Amex and Other Sources

The current trading price per Share of each Fund (quoted in U.S. dollars) is published continuously under its ticker symbol as trades occur throughout each trading day on the consolidated tape, Reuters and/or Bloomberg and on the Managing Owner’s website at http://www.dbfunds.db.com , or any successor thereto.

The most recent end-of-day closing level of each Index is published under its own symbol as of the close of business for the Amex each trading day on the consolidated tape, Reuters and/or Bloomberg and on the Managing Owner’s website at http://www.dbfunds.db.com , or any successor thereto. The most recent end-of-day net asset value of each Fund is published under its own symbol as of the close of business on Reuters and/or Bloomberg and on the Managing Owner’s website at http://www.dbfunds.db.com , or any successor thereto. In addition, the most recent end-of-day net asset value of each Fund is published the following morning on the consolidated tape.

End of Day Index Closing Level Symbols; End-of-Day Net Asset Value Symbols

PowerShares DB Energy Fund. The end-of-day closing level of the DBLCI-OY Energy ER is published under the symbol DBENIX. The end-of-day net asset value of PowerShares DB Energy Fund is published under the symbol DBE.NV.

PowerShares DB Oil Fund. The end-of-day closing level of the DBLCI-OY CL ER is published under the symbol DBOLIX. The end-of-day net asset value of PowerShares DB Oil Fund is published under the symbol DBO.NV.

PowerShares DB Precious Metals Fund. The end-of-day closing level of the DBLCI-OY Precious Metals ER is published under the symbol DBPMIX. The end-of-day net asset value of PowerShares DB Precious Metals Fund is published under the symbol DBP.NV.

PowerShares DB Gold Fund. The end-of-day closing level of the DBLCI-OY GC ER is published under the symbol DGLDIX. The end-of-day net asset value of PowerShares DB Gold Fund is published under the symbol DGL.NV.

PowerShares DB Silver Fund. The end-of-day closing level of the DBLCI-OY SI ER is published under the symbol DBSLIX. The end-of-day net asset value of PowerShares DB Silver Fund is published under the symbol DBS.NV.

PowerShares DB Base Metals Fund. The end-of-day closing level of the DBLCI-OY Industrial Metals ER is published under the symbol DBBMIX. The end-of-day net asset value of PowerShares DB Base Metals Fund is published under the symbol DBB.NV.

PowerShares DB Agriculture Fund. The end-of-day closing level of the DBLCI-OY Agriculture ER is published under the symbol DBAGIX. The end-of-day net asset value of PowerShares DB Agriculture Fund is published under the symbol DBA.NV.

The Managing Owner publishes the net asset value of each Fund and the net asset value per Share of each Fund daily. Additionally, the Index Sponsor publishes the intra-day level of each Index, and the Managing Owner will publish the indicative value per Share of each Fund (quoted in U.S. dollars) once every fifteen seconds throughout each trading day on the consolidated tape, Reuters and/or Bloomberg and on the Managing Owner’s website at http://www.dbfunds.db.com , or any successor thereto. All of the foregoing information is published under the following symbols:

Intra-Day Index Level Symbols and Intra-Day Indicative Values Per Share Symbols

PowerShares DB Energy Fund. The intra-day index level of the DBLCI-OY Energy ER is published under the symbol DBENIX. The intra-day indicative value per Share of PowerShares DB Energy Fund is published under the symbol DBE.IV.

PowerShares DB Oil Fund. The intra-day index level of the DBLCI-OY CL ER is published under the symbol DBOLIX. The intra-day indicative value per Share of PowerShares DB Oil Fund is published under the symbol DBO.IV.

PowerShares DB Precious Metals Fund. The intra-day index level of the DBLCI-OY Precious Metals ER is published under the symbol DBPMIX. The intra-day indicative value per Share of PowerShares DB Precious Metals Fund is published under the symbol DBP.IV.

PowerShares DB Gold Fund. The intra-day index level of the DBLCI-OY GC ER is published under the symbol DGLDIX. The intra-day indicative value per Share of PowerShares DB Gold Fund is published under the symbol DGL.IV.

PowerShares DB Silver Fund. The intra-day index level of the DBLCI-OY SI ER is published under the symbol DBSLIX. The intra-day indicative value per Share of PowerShares DB Silver Fund is published under the symbol DBS.IV.

PowerShares DB Base Metals Fund. The intra-day index level of the DBLCI-OY Industrial Metals ER is published under the symbol DBBMIX. The intra-day indicative value per Share of PowerShares DB Base Metals Fund is published under the symbol DBB.IV.

PowerShares DB Agriculture Fund. The intra-day index level of the DBLCI-OY Agriculture ER is published under the symbol DBAGIX. The intra-day indicative value per Share of PowerShares DB Agriculture Fund is published under the symbol DBA.IV.

Each Index’s history is also available at https://index.db.com .

The Index Sponsor obtains information for inclusion in, or for use in the calculation of, the Indexes from sources the Index Sponsor considers reliable. None of the Index Sponsor, the Managing Owner, the Funds,

the Master Funds or any of their respective affiliates accepts responsibility for or guarantees the accuracy and/or completeness of any of the Indexes or any data included in any of the Indexes.

CUSIP Numbers

The CUSIP number of PowerShares DB Energy Fund is 73936B101.

The CUSIP number of PowerShares DB Oil Fund is 73936B507.

The CUSIP number of PowerShares DB Precious Metals Fund is 73936B200.

The CUSIP number of PowerShares DB Gold Fund is 73936B606.

The CUSIP number of PowerShares DB Silver Fund is 73936B309.

The CUSIP number of PowerShares DB Base Metals Fund is 73936B705.

The CUSIP number of PowerShares DB Agriculture Fund is 73936B408.

The Master-Feeder Structure

Each Fund invests substantially all of its assets in a separate Master Fund in a master-feeder structure. Each Fund holds no investment assets other than Master Fund Units of its corresponding Master Fund. Each Master Fund is wholly-owned by its corresponding Fund and the Managing Owner. Each Share issued by a Fund correlates with a Master Fund Unit issued by such Fund’s corresponding Master Fund and held by such Fund.

Risk Factors

An investment in Shares of any Fund is speculative and involves a high degree of risk. The summary risk factors set forth below are intended merely to highlight certain risks that are common to all the Funds. Each Fund has particular risks that are set forth elsewhere in this Prospectus.

Each Fund and its corresponding Master Fund is subject to the approximate fees and expenses in the aggregate amounts per annum set forth in the above table and elsewhere in this Prospectus. Each Fund and its corresponding Master Fund will be successful only if their annual returns from futures trading, plus their annual interest income from their holdings of United States Treasury securities and other high credit quality short-term fixed income securities, exceed these fees and expenses. Because it is expected that interest income will exceed the fees and costs incurred by each Fund and Master Fund at the end of the first twelve months of an investment, the percentage of profit required for each Fund to breakeven at the end of the first twelve months of an investment, by definition, is expected to be 0.00%. Each Master Fund (and, in turn, each Fund) is expected to earn interest income equal to 1.66% per annum, based upon the yield of 3-month U.S. Treasury bills as of July 11, 2008. Therefore, based upon the difference

between the current yield of 3-month U.S. Treasury bills and the annual fees and expenses, each Fund is expected to have net income equal to or greater than the approximate amount per annum set forth in the above table, assuming that each Fund does not experience gains or losses from its futures trading. Actual interest income could be higher or lower than the current yield of 3-month U.S. Treasury bill.

The Trustee

Wilmington Trust Company, or the Trustee, a Delaware banking corporation, is the sole trustee of the Trust and the Master Trust. The Trustee delegated to the Managing Owner all of the power and authority to manage the business and affairs of the Trust and each Fund and the Master Trust and each Master Fund and has only nominal duties and liabilities to the Trust, the Funds, the Master Trust and the Master Funds.

Investment Objective

Each Fund and its corresponding Master Fund seeks to track changes, whether positive or negative, in the level of its corresponding Index over time, plus the excess, if any, of its corresponding Master Fund’s interest income from its holdings of United States Treasury and other high credit quality short-term fixed income securities over the expenses of each Fund and its corresponding Master Fund. The Shares of each Fund are designed for investors who want a cost-effective and convenient way to invest in commodity futures on U.S. and non-U.S. markets.

Advantages of investing in the Shares include:

Investing in the Shares does not insulate Shareholders from certain risks, including price volatility.

Each Fund pursues its investment objective by investing substantially all of its assets in its corresponding Master Fund. Each Master Fund pursues its investment objective by investing in a portfolio of exchange-traded futures on the commodities comprising the corresponding Index.

The Trust is comprised of each of the following Funds, each of which, in turn, intends to reflect the below sectors:

If the Managing Owner determines in its commercially reasonable judgment that it has become impracticable or inefficient for any reason for any Master Fund to gain full or partial exposure to any Index Commodity by investing in a specific futures contract that comprises the applicable Index, such Master Fund may invest in a futures contract referencing the particular Index Commodity other than the specific contract that comprises the applicable Index or, in the alternative, invest in other futures contracts not based on the particular Index Commodity if, in the commercially reasonable judgment of the Managing Owner, such

futures contracts tend to exhibit trading prices that correlate with a futures contract that comprises the applicable Index.

The Index Sponsor calculates each Index on both an excess return basis and a total return basis. The excess return basis calculation reflects the change in market value over time, whether positive or negative, of the applicable underlying commodity futures only. The total return basis calculation reflects the sum of the change in market value over time, whether positive or negative, of the applicable underlying commodity futures plus the return on 3-month U.S. Treasury bills. Each Fund and its corresponding Master Fund seeks to track changes, whether positive or negative, in the level of its corresponding Index over time, plus the excess, if any, of its corresponding Master Fund’s interest income from its holdings of United States Treasury and other high credit quality short-term fixed income securities over the expenses of each Fund’s and its corresponding Master Fund’s expenses.

Each Fund will make distributions at the discretion of the Managing Owner. To the extent that a Master Fund’s actual and projected interest income from its holdings of United States Treasury securities and other high credit quality short-term fixed income securities exceeds the actual and projected fees and expenses of such Master Fund and its corresponding Fund, the Managing Owner expects periodically to make distributions of the amount of such excess. The Funds currently do not expect to make distributions with respect to capital gains. Depending on the applicable Fund’s performance for the taxable year and your own tax situation for such year, your income tax liability for the taxable year for your allocable share of such Fund’s net ordinary income or loss and capital gain or loss may exceed any distributions you receive with respect to such year.

The Master Fund’s portfolio also will include United States Treasury securities and other high credit quality short-term fixed income securities for deposit with the Master Fund’s Commodity Broker as margin.

General

The Deutsche Bank Liquid Commodity Index–Optimum Yield Excess Return™, or DBLCI-OYER™, is intended to reflect the changes in market value, positive or negative, in certain sectors of commodities, or an Index. Each Index is (i) calculated on an excess return, or

unfunded basis and (ii) rolled in a manner which is aimed at potentially maximizing the roll benefits in backwardated markets and minimizing the losses from rolling in contangoed markets. Each Index is comprised of one or more underlying commodities, or Index Commodities. The composition of Index Commodities with respect to each Index varies according to each specific sector that such Index intends to reflect. Each Index Commodity is assigned a weight, or Index Base Weight, which is intended to reflect the proportion of such Index Commodity relative to each Index.

DBLCI-OY CL ER™, DBLCI-OY GC ER™ and DBLCI-OY SI ER™ are Indexes with a single Index Commodity, or Single Commodity Sector Indexes.

Each Index has been calculated back to a base date, or Base Date. On the Base Date the closing level of each Index, or Closing Level, was 100.

The sponsor of each Index is Deutsche Bank AG London, or Index Sponsor.

Each Index, except each Single Commodity Sector Index, is composed of notional amounts of each of the underlying Index Commodities. Each Single Commodity Sector Index is composed of one underlying Index Commodity. The notional amount of each Index Commodity included in each multi-sector Index is intended to reflect the changes in market value of each such Index Commodity within the specific Index. The Closing Level of each Index is calculated on each business day by the Index Sponsor based on the closing price of the futures contracts for each of the underlying Index Commodities and the notional amounts of such Index Commodities.

Each Index, excluding each Single Commodity Sector Index, is rebalanced annually in November to ensure that each of the Index Commodities is weighted in the same proportion that such Index Commodities were weighted on the Base Date.

The composition of each Index may be adjusted in the event that the Index Sponsor is not able to calculate the closing prices of the Index Commodities.

Each Index includes provisions for the replacement of futures contracts as they approach maturity. This replacement takes place over a period of time in order to lessen the impact on the market for the futures contracts being replaced. With respect to each Index Commodity,

the Master Fund employs a rule-based approach when it ‘rolls’ from one futures contract to another. Rather than select a new futures contract based on a predetermined schedule (e.g., monthly), each Index Commodity rolls to the futures contract which generates the best possible ‘implied roll yield.’ The futures contract with a delivery month within the next thirteen months which generates the best possible implied roll yield will be included in each Index. As a result, each Index Commodity is able to potentially maximize the roll benefits in backwardated markets and minimize the losses from rolling in contangoed markets.

In general, as a futures contract approaches its expiration date, its price will move towards the spot price in a contangoed market. Assuming the spot price does not change, this would result in the futures contract price decreasing and a negative implied roll yield. The opposite is true in a backwardated market. Rolling in a contangoed market will tend to cause a drag on an Index Commodity’s contribution to the Fund’s return while rolling in a backwardated market will tend to cause a push on an Index Commodity’s contribution to the Fund’s return.

The futures contract price for each Index Commodity will be the exchange closing price for such Index Commodity on each weekday when banks in New York, New York are open, or Index Business Days. If a weekday is not an Exchange Business Day (as defined in the following sentence) but is an Index Business Day, the exchange closing price from the previous Index Business Day will be used for each Index Commodity. “Exchange Business Day” means, in respect of an Index Commodity, a day that is a trading day for such Index Commodity on the relevant exchange (unless either an Index disruption event or force majeure event has occurred).

On the first New York business day, or Verification Date, of each month, each Index Commodity futures contract will be tested in order to determine whether to continue including it in the applicable Index. If the Index Commodity futures contract requires delivery of the underlying commodity in the next month, known as the Delivery Month, a new Index Commodity futures contract will be selected for inclusion in such Index. For example, if the first New York business day is May 1, 2009, and the Delivery Month of the Index Commodity futures contract currently in such Index is June 2009, a new Index Commodity futures contract with a later Delivery Month will be selected.

For each underlying Index Commodity of an Index, the new Index Commodity futures contract selected will be the Index Commodity futures contract with the best possible “implied roll yield” based on the closing price for each eligible Index Commodity futures contract. Eligible Index Commodity futures contracts are any Index Commodity futures contracts having a Delivery Month (i) no sooner than the month after the Delivery Month of the Index Commodity futures contract currently in such Index, and (ii) no later than the 13 ^th month after the Verification Date. For example, if the first New York business day is May 1, 2009 and the Delivery Month of an Index Commodity futures contract currently in an Index is therefore June 2009, the Delivery Month of an eligible new Index Commodity futures contract must be between July 2009 and July 2010. The implied roll yield is then calculated and the futures contract on the Index Commodity with the best possible implied roll yield is then selected. If two futures contracts have the same implied roll yield, the futures contract with the minimum number of months prior to the Delivery Month is selected.

After the futures contract selection, the monthly roll for each Index Commodity subject to a roll in that particular month unwinds the old futures contract and enters a position in the new futures contract. This takes place between the 2 ^nd and 6 ^th Index Business Day of the month.

On each day during the roll period, new notional holdings are calculated. The calculations for the old Index Commodities that are leaving an Index and the new Index Commodities are then calculated.

On all days that are not monthly index roll days, the notional holdings of each Index Commodity future remains constant.

Each Index is re-weighted on an annual basis on the 6 ^th Index Business Day of each November.

The calculation of each Index is expressed as the weighted average return of the Index Commodities.

DBLCI™ and Deutsche Bank Liquid Commodity Index™ are trade marks of the Index Sponsor and are the subject of Community Trade Mark Nos. 3055043 and 3054996. Trade Mark applications in the United States are pending with respect to both the Trust and aspects of each Index. Any use of these marks must be with the consent of or under license from the Index Sponsor. The Fund, Master Fund and the Managing

Owner have been licensed to use DBLCI™ and Deutsche Bank Liquid Commodity Index™. The Index Sponsor does not approve, endorse or recommend the Fund, the Master Fund or the Managing Owner.

There can be no assurance that any Fund or Master Fund will achieve its investment objective or avoid substantial losses. The Master Funds have limited performance history. The value of the Shares of each Fund is expected to fluctuate generally in relation to changes in the value of its corresponding Master Fund Units.

Shares of Each Fund Should Track Closely the Value of its Index

The Shares of each Fund are intended to provide investment results that generally correspond to changes, positive or negative, in the levels of the Fund’s corresponding Index, over time.

The value of the Shares of each Fund is expected to fluctuate in relation to changes in the value of its corresponding Master Fund’s portfolio. The market price of the Shares of a Fund may not be identical to the net asset value per Share, but these two valuations are expected to be very close.

Each Master Fund holds a portfolio of long futures contracts on the Index Commodities which comprise its corresponding Index, each of which are traded on various commodity futures markets in the United States and abroad. Each Master Fund also holds cash and United States Treasury securities and other high credit quality short-term fixed income securities for deposit with its Commodity Broker as margin. Each Master Fund’s portfolio is traded with a view to tracking the changes in its corresponding Index over time, whether the Index is rising, falling or flat over any particular period. None of the Master Funds is “managed” by traditional methods, which typically involve effecting changes in the composition of a portfolio on the basis of judgments relating to economic, financial and market considerations with a view to obtaining positive results under all market conditions.

The Managing Owner

DB Commodity Services LLC, a Delaware limited liability company, serves as Managing Owner of the Trust and each Fund and the Master Trust and each Master Fund. The Managing Owner was formed on May 23, 2005. The Managing Owner is an affiliate of

Deutsche Bank AG. The Managing Owner serves as the commodity pool operator and commodity trading advisor of the Trust and each Fund and the Master Trust and each Master Fund. The Managing Owner and its trading principals have limited experience in operating commodity pools and in managing futures trading accounts. The Managing Owner is registered as a commodity pool operator and commodity trading advisor with the Commodity Futures Trading Commission, or the CFTC, and is a member of the National Futures Association, or the NFA. As a registered commodity pool operator and commodity trading advisor, with respect to both the Trust and each Fund and the Master Trust and each Master Fund, the Managing Owner must comply with various regulatory requirements under the Commodity Exchange Act and the rules and regulations of the CFTC and the NFA, including investor protection requirements, antifraud prohibitions, disclosure requirements, and reporting and recordkeeping requirements. The Managing Owner is also subject to periodic inspections and audits by the CFTC and NFA.

The Shares are not deposits or other obligations of the Managing Owner, the Trustee or any of their respective subsidiaries or affiliates or any other bank, are not guaranteed by the Managing Owner, the Trustee or any of their respective subsidiaries or affiliates or any other bank and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency. An investment in the Shares of any Fund is speculative and involves a high degree of risk.

The principal office of the Managing Owner is located at 60 Wall Street, New York, New York 10005. The telephone number of the Managing Owner is (212) 250-5883.

Each Master Fund pays the Managing Owner a Management Fee, monthly in arrears, in an amount equal to either:

No separate fee is paid by any Fund. The Management Fee is paid in consideration of the Managing Owner’s commodity futures trading advisory services.

The Commodity Broker

A variety of executing brokers execute futures transactions on behalf of the Master Funds. Such executing brokers give-up all such transactions to Deutsche Bank Securities Inc., a Delaware corporation, which serves as clearing broker, or Commodity Broker of each of the Master Funds. The Commodity Broker is an affiliate of the Managing Owner. In its capacity as clearing broker, the Commodity Broker executes and clears each Master Fund’s futures transactions and performs certain administrative services for each Master Fund. Deutsche Bank Securities Inc. is registered with the CFTC as a futures commission merchant and is a member of the NFA in such capacity.

Each Master Fund pays to the Commodity Broker all brokerage commissions, including applicable exchange fees, NFA fees, give-up fees, pit brokerage fees and other transaction related fees and expenses charged in connection with trading activities for each Master Fund. On average, total charges paid to the Commodity Broker are expected to be less than $10.00 per round-turn trade, although the Commodity Broker’s brokerage commissions and trading fees are determined on a contract-by-contract basis. The Managing Owner does not expect brokerage commissions and fees to exceed:

in any year, although the actual amount of brokerage commissions and fees in any year or any part of any year may be greater.

A round-turn trade is a completed transaction involving both a purchase and a liquidating sale, or a sale followed by a covering purchase.

The Administrator

The Trust and Master Trust, on behalf of each Fund and each Master Fund, respectively, has appointed The Bank of New York as the administrator, or the Administrator, of each Fund and each Master Fund and has entered into an Administration Agreement in connection therewith. The Bank of New York serves as custodian, or Custodian, of each Fund and has entered into a Global Custody Agreement, or Custody Agreement, in connection therewith. The Bank of New York serves as the transfer agent, or Transfer Agent, of each Fund and has entered into a Transfer Agency and Service Agreement in connection therewith.

The Bank of New York, a banking corporation organized under the laws of the State of New York with trust powers, has an office at 2 Hanson Place, 12 ^th Floor, Brooklyn, N.Y. 11217. The Bank of New York is subject to supervision by the New York State Banking Department and the Board of Governors of the Federal Reserve System. Information regarding the net asset value of each Fund, creation and redemption transaction fees and the names of the parties that have executed a Participant Agreement may be obtained from The Bank of New York by calling the following number: (718) 315-4412. A copy of the Administration Agreement is available for inspection at The Bank of New York’s trust office identified above.

Pursuant to the Administration Agreement, the Administrator performs or supervises the performance of services necessary for the operation and administration of each Fund and each Master Fund (other than making investment decisions), including receiving and processing orders from Authorized Participants to create and redeem Baskets, net asset value calculations, accounting and other fund administrative services. The Administrator retains, separately for each Fund and each Master Fund, certain financial books and records, including: Basket creation and redemption books and records, Fund and Master Fund accounting records, ledgers with respect to assets, liabilities, capital, income and expenses, the registrar, transfer journals and related details and trading and related documents received from futures commission merchants, c/o The Bank of New York, 2 Hanson

Place, 12 ^th Floor, Brooklyn, New York 11217, telephone number (718) 315-4850.

The Administration Agreement will continue in effect from the commencement of trading operations unless terminated on at least 90 days’ prior written notice by either party to the other party. Notwithstanding the foregoing, the Administrator may terminate the Administration Agreement upon 30 days’ prior written notice if any Fund and/or any Master Fund has materially failed to perform its obligations under the Administration Agreement.

The Administration Agreement provides for the exculpation and indemnification of the Administrator from and against any costs, expenses, damages, liabilities or claims (other than those resulting from the Administrator’s own bad faith, negligence or willful misconduct) which may be imposed on, incurred by or asserted against the Administrator in performing its obligations or duties under the Administration Agreement. Key terms of the Administration Agreement are summarized under the heading “Material Contracts.”

The Administrator’s monthly fees are paid on behalf of each Fund and each Master Fund by the Managing Owner out of the applicable Management Fee.

The Administrator and any of its affiliates may from time-to-time purchase or sell Shares for their own account, as agent for their customers and for accounts over which they exercise investment discretion.

The Administrator also receives a transaction processing fee in connection with orders from Authorized Participants to create or redeem Baskets in the amount of $500 per order. These transaction processing fees are paid indirectly by the Authorized Participants and not by any Fund or any Master Fund.

Each Fund is expected to retain the services of one or more additional service providers to assist with certain tax reporting requirements of each Fund and the Shareholders of each Fund.

ALPS Distributors, Inc.

The Trust, on behalf of each Fund, has appointed ALPS Distributors, Inc., or ALPS Distributors, to assist the Managing Owner and the Administrator with certain functions and duties relating to distribution and

marketing, including reviewing and approving marketing materials. ALPS Distributors retains all marketing materials separately for each Fund and each Master Fund, at c/o ALPS Distributors, Inc., 1290 Broadway, Suite 1100, Denver, Colorado 80203; telephone number (303) 623-2577. Investors may contact ALPS Distributors toll-free in the U.S. at (877) 369-4617. The Managing Owner, on behalf of each Fund, has entered into a Distribution Services Agreement with ALPS Distributors. ALPS Distributors is affiliated with ALPS Fund Services, Inc., a Denver-based outsourcing solution for administration, compliance, fund accounting, legal, marketing, tax administration, transfer agency and shareholder services for open-end, closed-end, hedge and exchange-traded funds, with over 350,000 shareholder accounts and approximately $17 billion in client mutual fund assets under administration. ALPS Distributors provides distribution services to approximately $232 billion in client assets.

The Managing Owner, out of the relevant Management Fee, pays ALPS Distributors for performing its duties on behalf of each Fund and its corresponding Master Fund and may pay ALPS Distributors additional compensation in consideration of the performance by ALPS Distributors of additional marketing, distribution and ongoing support services to such Fund or its corresponding Master Fund. Such additional services may include, among other services, the development and implementation of a marketing plan and the utilization of ALPS Distributors’ resources, which include an extensive broker database and a network of internal and external wholesalers.

ALPS Distributors, Inc. is the distributor of PowerShares DB Energy Fund, PowerShares DB Oil Fund, PowerShares DB Precious Metals Fund, PowerShares DB Gold Fund, PowerShares DB Silver Fund, PowerShares DB Base Metals Fund and PowerShares DB Agriculture Fund. Certain marketing services may be provided for each Fund by Invesco Aim Distributors, Inc. or Invesco PowerShares Capital Management, LLC. This assistance includes the licensing of the PowerShares ^® registered service mark to the Managing Owner for use with each Fund. PowerShares ^® is a registered service mark of Invesco PowerShares Capital Management LLC. Invesco PowerShares Capital Management LLC is not a sponsor or promoter of any of the Funds and has no responsibility for the performance of any of the Funds or the decisions made or actions taken by the Managing Owner.

“800” Number for Investors

Investors may contact Invesco PowerShares Capital Management LLC toll free in the U.S. at (800) 983-0903.

Invesco Aim Distributors, Inc.

Through a marketing agreement between the Managing Owner and Invesco Aim Distributors, Inc. (formerly known as A I M Distributors, Inc.), or Invesco Aim Distributors, an affiliate of Invesco PowerShares Capital Management LLC (formerly known as PowerShares Capital Management LLC), or Invesco PowerShares, the Managing Owner, on behalf of each Fund and each Master Fund, has appointed Invesco Aim Distributors as a marketing agent. Invesco Aim Distributors assists the Managing Owner and the Administrator with certain functions and duties such as providing various educational and marketing activities regarding each Fund, primarily in the secondary trading market, which activities include, but are not limited to, communicating each Fund’s name, characteristics, uses, benefits, and risks, consistent with this Prospectus. Invesco Aim Distributors will not open or maintain customer accounts or handle orders for each Fund. Invesco Aim Distributors is a subsidiary of Invesco Ltd. Invesco Ltd. is a leading independent global investment manager operating under the AIM, Atlantic Trust, Invesco, Perpetual, PowerShares, Trimark and WL Ross brands.

The Managing Owner, out of the relevant Management Fee, pays Invesco Aim Distributors for performing its duties on behalf of each Fund and its corresponding Master Fund.

Limitation of Liabilities

Although the Managing Owner has unlimited liability for any obligations of each Fund that exceed that Fund’s net assets, your investment in a Fund is part of the assets of that Fund, and it will therefore be subject to the risks of that Fund’s trading only. You cannot lose more than your investment in any Fund, and you will not be subject to the losses or liabilities of any Fund in which you have not invested. We have received an opinion of counsel that each Fund is entitled to the benefits of the limitation on inter-series liability provided under the Delaware Statutory Trust Act. Each Share, when purchased in accordance with the Declaration of Trust, shall, except as otherwise provided by law, be fully-paid and non-assessable.

The debts, liabilities, obligations, claims and expenses of a particular Fund will be enforceable against the assets of that Fund only, and not against the assets of the Trust generally or the assets of any other Fund or of any Master Fund, and, unless otherwise provided in the Declaration of Trust, none of the debts, liabilities, obligations and expenses incurred, contracted for or otherwise existing with respect to the Trust or Master Trust generally or any other series thereof will be enforceable against the assets of such Fund or Master Fund, as the case may be.

Creation and Redemption of Shares

The Funds create and redeem Shares from time-to-time, but only in one or more Baskets. A Basket is a block of 200,000 Shares. Baskets may be created or redeemed only by Authorized Participants. Except when aggregated in Baskets, the Shares are not redeemable securities. Authorized Participants pay a transaction fee of $500 in connection with each order to create or redeem a Basket. Authorized Participants may sell the Shares included in the Baskets they purchase from the Funds to other investors.

The Master Funds create and redeem Master Fund Units from time-to-time, but only in one or more Master Unit Baskets. A Master Unit Basket is a block of 200,000 Master Fund Units. Master Unit Baskets in a particular Master Fund may be created or redeemed only by its corresponding Fund. Each Master Fund is wholly-owned by its corresponding Fund and the Managing Owner. Each Share issued by its corresponding Fund correlates with a Master Fund Unit issued by its corresponding Master Fund and held by such Fund.

See “Creation and Redemption of Shares” for more details.

The Offering

Each Fund issues Shares in Baskets to Authorized Participants continuously as of noon, New York time, on the business day immediately following the date on which a valid order to create a Basket is accepted by the Fund, at the net asset value of 200,000 Shares of the Fund as of the closing time of the Amex or the last to close of the exchanges on which the corresponding Master Fund’s futures contracts are traded, whichever is later, on the date that a valid order to create a Basket is accepted by the Fund.

Each Master Fund issues Master Fund Units in Master Unit Baskets to its corresponding Fund continuously as of noon, New York time, on the business day immediately following the date on which a valid order to create a Master Unit Basket is accepted by the Master Fund, at the net asset value of 200,000 Master Fund Units as of the closing time of the Amex or the last to close of the exchanges on which the corresponding Master Fund’s futures contracts are traded, whichever is later, on the date that a valid order to create a Master Unit Basket is accepted by the Master Fund. Each Master Fund is wholly-owned by its corresponding Fund and the Managing Owner. Each Share issued by a Fund correlates with a Master Fund Unit issued by its corresponding Master Fund and held by the Fund.

Authorized Participants

Baskets may be created or redeemed only by Authorized Participants. Each Authorized Participant must (1) be a registered broker-dealer or other securities market participant such as a bank or other financial institution which is not required to register as a broker-dealer to engage in securities transactions, (2) be a participant in DTC, and (3) have entered into an agreement with each Fund and the Managing Owner (a Participant Agreement). The Participant Agreement sets forth the procedures for the creation and redemption of Baskets of Shares and for the delivery of cash required for such creations or redemptions. A list of the current Authorized Participants can be obtained from the Administrator. A similar agreement between each Fund and its corresponding Master Fund sets forth the procedures for the creation and redemption of Master Unit Baskets by the Funds. See “Creation and Redemption of Shares” for more details.

Net Asset Value

Net asset value, in respect of any Master Fund, means the total assets of the Master Fund including, but not limited to, all cash and cash equivalents or other debt securities less total liabilities of such Master Fund, each determined on the basis of generally accepted accounting principles in the United States, consistently applied under the accrual method of accounting.

Net asset value per Master Fund Unit, in respect of any Master Fund, is the net asset value of the Master Fund divided by the number of its outstanding Master Fund Units. Because there is a one-to-one correlation

between Shares of a Fund and Master Fund Units of its corresponding Master Fund and each Master Fund has assumed all liabilities of its corresponding Fund, the net asset value per Share of any Fund and the net asset value per Master Fund Unit of its corresponding Master Fund is equal.

See “Description of the Shares and the Master Fund Units; The Funds; Certain Material Terms of the Trust Declarations – Net Asset Value” for more details.

Clearance and Settlement

The Shares of each Fund are evidenced by global certificates that the Fund issues to DTC. The Shares of each Fund are available only in book-entry form. Shareholders may hold Shares of any Fund through DTC, if they are participants in DTC, or indirectly through entities that are participants in DTC. The Master Fund Units of each Master Fund are uncertificated and held by its corresponding Fund in book-entry form.

Segregated Accounts/Interest Income

The proceeds of the offering of each Fund are deposited in cash in a segregated account in the name of its corresponding Master Fund at the Commodity Broker (or another eligible financial institution, as applicable) in accordance with CFTC investor protection and segregation requirements. Each Master Fund is credited with 100% of the interest earned on its average net assets on deposit with the Commodity Broker or such other financial institution each week. In an attempt to increase interest income earned, the Managing Owner expects to invest non-margin assets of each Master Fund in United States government securities (which include any security issued or guaranteed as to principal or interest by the United States), or any certificate of deposit for any of the foregoing, including United States Treasury bonds, United States Treasury bills and issues of agencies of the United States government, and certain cash items such as money market funds, certificates of deposit (under nine months) and time deposits or other instruments permitted by applicable rules and regulations. Currently, the rate of interest expected to be earned by each Master Fund is estimated to be 1.66% per annum, based upon the yield on 3-month U.S. Treasury bills as of July 11, 2008. This interest income is used by each Master Fund to pay its own expenses and the expenses of its corresponding Fund. See “Fees and Expenses” for more details.

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Units and will take into account their allocable share of such Master Fund’s income, gain and loss when testing compliance with the asset, income and other statutory requirements specifically applicable to them. A Fund will be treated as a qualified publicly traded partnership (“qualified PTP”) within the meaning of the Internal Revenue Code of 1986, as amended, or the Code, for purposes of satisfying the qualification requirements specifically applicable to RICs for any taxable year in which its corresponding Master Fund realizes sufficient gross income from its commodity futures transactions. Prospective RIC investors should consult a tax adviser regarding the treatment of an investment in a Fund (and its corresponding Master Fund) to them under current tax rules. See “Material U.S. Federal Income Tax Considerations—Regulated Investment Companies” below.

Additionally, please refer to the “Material U.S. Federal Income Tax Considerations” section below for information on the potential U.S. federal income tax consequences of the purchase, ownership and disposition of Shares of a Fund.

“Breakeven Table”

The “Breakeven Table” on the following page indicates the approximate percentage and dollar returns required for the value of an initial $25.00 investment in a Share of each Fund to equal the amount originally invested twelve months after issuance.

The “Breakeven Table,” as presented, is an approximation only. The capitalization of each Fund does not directly affect the level of its charges as a percentage of its net asset value, other than brokerage commissions.

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Incorporation by Reference of Certain Documents

The Securities and Exchange Commission, or the SEC, allows us to “incorporate by reference” the information that we file with it, meaning we can disclose important information to you by referring you to those documents already on file with the SEC.

This filing incorporates by reference the following documents, which we have previously filed with the SEC, in response to certain disclosures pursuant to Item 11 of Form S-1:

The Annual Reports on Form 10-K for the fiscal year ended December 31, 2007, as filed on March 26, 2008 with respect to each of the following:

The Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2008, as filed on May 9, 2008 with respect to PowerShares DB Agriculture Fund, a series of PowerShares DB Multi-Sector Commodity Trust and DB Agriculture Master Fund, a series of DB Multi-Sector Commodity Master Trust;

The Quarterly Reports on Form 10-Q for the fiscal quarter ended March 31, 2008, as filed on May 14, 2008 with respect to each of the following:

The Current Report on Form 8-K filed on February 20, 2008 with respect to PowerShares DB Multi-Sector Commodity Trust and DB Multi-Sector Commodity Master Trust.

The Current Report on Form 8-K filed on February 28, 2008 with respect to PowerShares DB Agriculture Fund, a series of PowerShares DB Multi-Sector Commodity Trust and DB Agriculture Master Fund, a series of DB Multi-Sector Commodity Master Trust.

The Current Report on Form 8-K filed on April 11, 2008 with respect to PowerShares DB Multi-Sector Commodity Trust and DB Multi-Sector Commodity Master Trust.

The Current Report on Form 8-K filed on June 23, 2008 with respect to PowerShares DB Multi-Sector Commodity Trust and DB Multi-Sector Commodity Master Trust.

Any statement contained in a document that is incorporated by reference will be modified or superseded for all purposes to the extent that a statement contained in this Prospectus modifies or is contrary to that previous statement. Any statement so modified or superseded will not be deemed a part of this Prospectus except as so modified or superseded.

We will provide to you a copy of the filings that have been incorporated by reference in this Prospectus upon your request, at no cost. Any request may be made by writing or calling us at the following address or telephone number:

Invesco PowerShares Capital Management LLC

301 West Roosevelt Road

Wheaton, IL 60187

Telephone: (800) 983-0903

These documents may also be accessed through our website at www.dbfunds.db.com or as described under “Additional Information.” The information and other content contained on or linked from our website is not incorporated by reference in this Prospectus and should not be considered a part of this Prospectus.

We file annual, quarterly, current reports and other information with the SEC. You may read and copy these materials at the SEC’s Public Reference Room at 100 F Street, NW, Washington, DC 20549. The public may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC maintains an internet site at http://www.sec.gov that contains reports, proxy and information statements and other information regarding the company.

Reports to Shareholders

The Managing Owner will furnish you with an annual report of each Fund in which you are invested within 90 calendar days after the end of such Fund’s fiscal year as required by the rules and regulations of the SEC as well as with those reports required by the CFTC and the NFA, including, but not limited to, an annual audited financial statement certified by independent registered public accountants and any other reports required by any other governmental authority that has jurisdiction over the activities of the Funds and the Master Funds. You also will be provided with appropriate information to permit you to file your U.S. federal and state income tax returns (on a timely basis) with respect to your Shares. Monthly account statements conforming to CFTC and NFA requirements are posted on the Managing Owner’s website at www.dbfunds.db.com . Additional reports may be posted on the Fund’s website in the discretion of the Managing Owner or as required by regulatory authorities.

Cautionary Note Regarding Forward-Looking Statements

This Prospectus includes forward-looking statements that reflect the Managing Owner’s current expectations about the future results, performance, prospects and opportunities of the Funds and the Master Funds. The Managing Owner has tried to identify these forward-looking statements by using words such as “may,” “will,” “expect,” “anticipate,” “believe,” “intend,” “should,” “estimate” or the negative of those terms or similar expressions. These forward-looking statements are based on information currently available to the Managing Owner and are subject to a number of risks, uncertainties and other factors, both known, such as those described in “Risk Factors” in this Summary, in “The Risks You Face” and elsewhere in this Prospectus, and unknown, that could cause the actual results, performance, prospects or opportunities of the Funds and the Master Funds to differ materially from those expressed in, or implied by, these forward-looking statements.

You should not place undue reliance on any forward-looking statements. Except as expressly required by the federal securities laws, the Managing Owner undertakes no obligation to publicly update or revise any forward-looking statements or the risks, uncertainties or other factors described in this Prospectus, as a result of new information, future events

or changed circumstances or for any other reason after the date of this Prospectus.

THE SHARES ARE SPECULATIVE AND INVOLVE A HIGH DEGREE OF RISK.

Patent Applications Pending

Patent applications directed to the creation and operation of the Trust and aspects of each Index are pending at the United States Patent and Trademark Office.

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