UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

For the quarterly period ended September 30, 2009

OR

For the transition period from                  to                

Commission File Number 0-23240

BLACKROCK GLOBAL HORIZONS I L.P.

(Exact Name of Registrant as

specified in its charter)

c/o BlackRock Investment Management LLC

40 East 52nd Street

New York, New York 10022

(Address of principal executive offices)

(Zip Code)

609-282-6996

(Registrant’s telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.  Yes x  No o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).  Yes o  No o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer or a non-accelerated filer (as defined in Rule 12b-2 of the Exchange Act).  See definition of “accelerated and large accelerated filer” in Rule 12b-2 of the Exchange Act. (Check one)

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).  Yes o  No x

BLACKROCK GLOBAL HORIZONS I L.P.

QUARTERLY REPORT FOR SEPTEMBER 30, 2009 ON FORM 10-Q

Table of Contents

PART I - FINANCIAL INFORMATION

Item 1.    Financial Statements

BLACKROCK GLOBAL HORIZONS I L.P.

(A DELAWARE LIMITED PARTNERSHIP)

STATEMENTS OF FINANCIAL CONDITION

(unaudited)

NET ASSET VALUE PER UNIT (Note 2)

See notes to financial statements.

2

BLACKROCK GLOBAL HORIZONS I L.P.

(A DELAWARE LIMITED PARTNERSHIP)

STATEMENTS OF OPERATIONS

(unaudited)

See notes to financial statements.

3

BLACKROCK GLOBAL HORIZONS I L.P.

(A DELAWARE LIMITED PARTNERSHIP)

STATEMENTS OF CHANGES IN PARTNERS’ CAPITAL

FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2009 AND 2008

(unaudited)

See notes to financial statements.

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BLACKROCK GLOBAL HORIZONS I L.P.

(A DELAWARE LIMITED PARTNERSHIP)

FINANCIAL DATA HIGHLIGHTS

FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2009

(unaudited)

The following per Unit data and ratios have been derived from information provided in the financial statements.  An individual Partner’s results may vary from these ratios due to timing of income and expenses and capital transactions.

(1) Included in the ratios of expenses to average net assets are brokerage commissions and clearing costs which are presented in Trading Profits (Losses) on the Statement of Operations.

(2) The expenses (before Profit Shares) and the interest portion of net investment loss for the net investment loss ratios have been annualized.

See notes to financial statements.

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BLACKROCK GLOBAL HORIZONS I L.P.

(A DELAWARE LIMITED PARTNERSHIP)

NOTES TO FINANCIAL STATEMENTS

(unaudited)

1.     SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

The interim financial information at September 30, 2009 and for the periods ended September 30, 2009 and September 30, 2008 is unaudited.  However, in the opinion of management, the financial statements contain all adjustments necessary to present fairly the financial position of BlackRock Global Horizons I L.P. (the “Partnership”) as of September 30, 2009 and December 31, 2008, and the results of its operations for the three and nine month periods ended September 30, 2009 and 2008. The operating results for the interim periods may not be indicative of the results for the full year.

Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“US GAAP”) have been omitted. These financial statements should be read in conjunction with the financial statements and notes thereto included in the Partnership’s Annual Report on Form 10-K filed with the Securities and Exchange Commission for the year ended December 31, 2008 (the “Form 10-K”).

The preparation of financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.  Actual results could differ from those estimates.

BlackRock Investment Management, LLC (the “General Partner” or “BRIM”), a wholly owned subsidiary of BlackRock, Inc. (“BlackRock”) is the general partner of the Partnership.

PFPC Trust Company (“PFPC Trust”), an affiliate of the General Partner, provides custody services for the Partnership. As of September 30, 2009 $191,734,763 was held in custody at PFPC Trust and invested in an affiliated BlackRock money market fund.  The Partnership’s assets will also be held in cash and customer segregated accounts at Merrill Lynch, Pierce, Fenner & Smith Incorporated (“MLPF&S”),  an affiliate of the General Partner, Newedge USA, LLC (“NUSA”) and any other clearing brokers that may be utilized by the Partnership in the future (the “Clearing Brokers”) or allocated to one or more Portfolio Funds for which custodians and clearing brokers are selected by the independent professional advisors of such Portfolio Funds or managed accounts (the “Trading Advisors”).

The Partnership has defined cash and cash equivalents as cash, money market funds and short-term, highly liquid investments with maturities of three months or less when acquired.  Money market funds, which are included in cash equivalents, are classified as Level 1 valuation inputs (quoted prices in active markets for identical assets) under the provisions of Accounting Standards Codification (“ASC”) 820-10, Fair Value Measurements and Disclosures (“ASC 820-10”) (Statement of Financial Accounting Standards (“SFAS”) No. 157, Fair Value Measurements).

On January 1, 2009, Bank of America Corp. announced that it had completed its acquisition of Merrill Lynch & Co., Inc. (“Merrill Lynch”), one of the largest shareholders of BlackRock, Inc.

The Partnership, in its normal course of business, enters into various derivatives contracts with MLPF&S and NUSA, each acting as the Partnership’s clearing brokers. Pursuant to the brokerage agreements with MLPF&S and NUSA (which include netting arrangements with each broker), to the extent that such

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trading results in receivables from and payables to MLPF&S and NUSA, these receivables and payables are offset and reported as a net receivable or payable with each broker.  Net receivables are included in the Statements of Financial Condition under Equity in commodity futures trading accounts in net unrealized profit on open contracts and net payables are included under Liabilities in net unrealized loss on open contracts.

2.               NET ASSET VALUE PER UNIT

At September 30, 2009 and December 31, 2008, the Net Asset Values of the different series of Units were:

3.               FAIR VALUE DISCLOSURES

Effective January 1, 2008, the Partnership adopted ASC 820-10. ASC 820-10 defines fair value as the price that the Partnership would receive upon selling an investment or pay to transfer a liability in an orderly transaction to a market participant in the principal or most advantageous market for the investment. ASC 820-10 emphasizes that valuation techniques maximize the use of observable market inputs and minimize the use of unobservable inputs. Inputs refer broadly to the assumptions that market participants would use in pricing an asset or liability, including assumptions about risk to the extent the asset or liability is not traded on an exchange or an active market.  Inputs may be observable or unobservable. Observable inputs are inputs that reflect the assumptions market participants would use in pricing an asset or liability developed based on market data obtained from sources independent of the Partnership. Unobservable inputs are inputs that reflect the General Partner assumptions about what information market participants would use to price an asset or liability developed based on the best information available under the circumstances.

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ASC 820-10 establishes a hierarchy that classifies these inputs into the three broad levels listed below:

·                                          Level 1 — Price quotations (unadjusted) in active markets/exchanges for identical instruments.

·                                          Level 2 — Other than quoted prices included within Level 1 that are observable for substantially the full term of the asset or liability, either directly or indirectly.  Level 2 includes quoted prices (unadjusted) for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities that are not active; and inputs other than quoted prices that are observable, such as those used in models or other valuation methodologies.

·                                          Level 3 — Primarily inputs and significant assumptions that are unobservable in the market place.  Level 3 assets include investments for which there is little, if any, market activity.  These inputs require significant judgment or estimation by the General Partner of the Partnership.

The following table summarizes the valuation of the Partnership’s investments by the above ASC 820-10  fair value hierarchy levels as of September 30, 2009.

4.   DERIVATIVE CONTRACTS AND OFF-BALANCE SHEET RISK

The Partnership trades in the international futures and forward markets with the objective of achieving, through speculative trading, substantial capital appreciation over time. The Partnership’s assets are allocated and reallocated by the General Partner to managed accounts managed by the Trading Advisors applying proprietary strategies in numerous markets.

The Partnership engages in the speculative trading of derivative contracts on interest rates, commodities, currencies, metals, energy, livestock and stock indices. The following were the primary trading risk exposures of such derivative contracts as of at September 30, 2009, organized by market sector:

Agricultural.  The Partnership’s primary exposure is to agricultural price movements, which are often directly affected by severe or unexpected weather conditions.

Currencies.  Exchange rate risk is a principal market exposure of the Partnership.  The Partnership’s currency exposure is to exchange rate fluctuations, primarily fluctuations which disrupt the historical pricing relationships between different currencies and currency pairs.  The fluctuations are influenced by interest rate changes as well as political and general economic conditions.  The Partnership trades in a large number of currencies, including cross-rates—e.g., positions between two currencies other than the U.S. dollar.

Energy.  The Partnership’s primary energy market exposure is to gas and oil price movements, often resulting from political developments in the Middle East and economic conditions worldwide.  Energy prices are volatile and substantial profits and losses have been and are expected to continue to be experienced in this market.

Interest rates.  Interest rate movements directly affect the price of the sovereign bond futures positions held by the Partnership and indirectly the value of its stock index and currency positions.  Interest rate

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movements in one country as well as relative interest rate movements between countries may materially impact the Partnership’s profitability.  The Partnership’s primary interest rate exposure is to interest rate fluctuations in the United States and other major industrialized, or Group of Seven countries (Canada, France, Germany, Italy, Japan, United Kingdom and United States, collectively, “G-7”).  However, the Partnership also may take positions in futures contracts on the government debt of other nations.  The General Partner anticipates that G-7 interest rates, both long-term and short-term, will remain the primary market exposure of the Partnership for the foreseeable future.

Metals. The Partnership’s metals market exposure is to fluctuations in the price of aluminum, copper, gold, lead, nickel, silver, tin and zinc.

Stock Indices.  The Partnership’s equity exposure, through stock index futures, is to equity price risk in the G-7 countries, as well as other countries.

The Partnership, through the trading activities of the Trading Advisors, also engages in the speculative trading of forward currency contracts. Substantially all of the Partnership’s off-exchange trading takes place in the highly liquid, institutional spot and forward foreign exchange markets (the “FX Markets”) where there are no direct execution costs. Instead, the participant banks and dealers in the FX Markets take a “spread” between the prices at which they are prepared to buy and sell a particular currency, and such spreads are built into the pricing of the spot or forward contracts traded with the Partnership. In its exchange of futures for physical (“EFP”) trading, the Partnership acquires cash currency positions through banks and dealers. The Partnership pays a spread when it exchanges these positions for futures. This spread reflects, in part, the different settlement dates of the cash and the futures contracts, as well as prevailing interest rates, but also includes a pricing spread in favor of the banks and dealers, which may include a Merrill Lynch entity.

The Partnership is exposed to both market risk, the risks arising from changes in the market value of the contracts, and credit risk, the risk of failure by another party to perform according to the terms of a contract.

Market Risk

Derivative contracts involve varying degrees of off-balance sheet market risk.  Changes in the level or volatility of interest rates, foreign currency exchange rates or the market values of the financial contracts or commodities underlying such derivative contracts frequently result in changes in the Partnership’s net unrealized profit (loss) on such derivative contracts as reflected in the Statements of Financial Condition.  The Partnership’s exposure to market risk is influenced by a number of factors, including the relationships among the derivative contracts held by the Partnership as well as the volatility and liquidity of the markets in which the derivative contracts are traded.  Investments in foreign markets may also entail legal and political risks.

BRIM has procedures in place intended to control market risk exposure, although there can be no assurance that they will, in fact, succeed in doing so.  These procedures focus primarily on monitoring the trading of the Trading Advisors, calculating the Net Asset Value of the Partnership as of the close of business on each day and reviewing outstanding positions, or reallocating Partnership assets among Trading Advisors (although typically only as of the end of a month) for over-concentrations.  While BRIM does not itself intervene in the markets to hedge or diversify the Partnership’s market exposure, BRIM may urge the Trading Advisors to reallocate positions in an attempt to avoid over-concentrations.  Except in cases in which it appears that the Trading Advisors have begun to deviate from past practice or

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trading policies or to be trading erratically, BRIM’s basic risk control procedures consist simply of the ongoing process of Trading Advisor monitoring, with the market risk controls being applied by the Trading Advisors themselves.

Credit Risk

The credit risks associated with exchange-traded contracts are typically perceived to be less than those associated with over-the-counter (non-exchange-traded) transactions.  This is because exchanges typically (but not universally) have clearinghouse arrangements in which margin deposits, a clearing fund and collective credit (in some cases limited in amount, in some cases not) of the members of the clearinghouse are segregated and pledged to support the financial integrity of the contracts traded on the exchange. In over-the-counter transactions, on the other hand, traders must rely solely on the credit of their respective individual counterparties. Margins, which may be subject to loss in the event of a default, are generally required in exchange trading, and counterparties may also require margin in the over-the-counter markets.

The amount of required margin and good faith deposits with the brokers usually ranges from 5% to 30% of Net Asset Value.  The market value of cash and securities held to satisfy such requirements at September 30, 2009 and December 31, 2008 was $19,436,079 and $10,090,467, respectively, which equals 7.83% and 4.42% of Net Asset Value, respectively.

The Partnership has a substantial portion of its assets on deposit with financial institutions.  In the event of a financial institution’s insolvency, recovery of Partnership assets on deposit may be limited to account insurance or other protection afforded such deposits.

For derivatives, risks arise from changes in the market value of the contracts.  Theoretically, the Partnership is exposed to a market risk equal to the notional contract value of futures and forward currency contracts purchased and unlimited liability on such contracts sold short.

The Partnership qualifies as an investment company under the provisions of the American Institute of Certified Public Accountants Audit and Accounting Guide for Investment Companies and therefore, all investments including derivatives are stated at fair value in the Statements of Financial Condition, and changes in fair value are included in realized and unrealized trading profits and losses in the Statements of Operations.

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Condensed Schedule of Investments

The Partnership trades futures and forward contracts.  The level of trading is affected by conditions in those markets.  During the quarter and nine months ended September 30, 2009, 102,325 and 267,526 contracts were closed, respectively.  The fair value of the Partnership’s futures and forward contracts by type, defined as Net unrealized profit on open contracts in the Statements of Financial Condition as of September 30, 2009 are as follows:

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The trading profits (losses) of the Partnership’s derivatives by instrument type, as well as the location of those gains and losses on the Statement of Operations for the three and nine month periods ended September 30, 2009 are as follows:

For the three months ended September 30 , 2009

For the nine months ended September 30 , 2009

5.               RECENT ACCOUNTING PRONOUNCEMENTS

In March 2008, FASB issued, ASC 815-19, Derivatives and Hedging (SFAS No. 161 Disclosures about Derivative Instruments and Hedging Activities — an amendment of FASB Statement No. 133 ).  ASC 815-19 expands the disclosure requirements for derivative instruments and hedging activities.  ASC 815-19 specifically requires enhanced disclosures addressing: a) how and why an entity uses derivative instruments, b) how derivative instruments and related hedged items are accounted for under SFAS No. 133, Accounting for Derivative Instruments and Hedging Activities, and its related interpretations and c) how derivative instruments and related hedged items affect an entity’s financial position, financial performance and cash flows.  ASC 815-19 is effective for fiscal years and interim periods beginning after November 15, 2008.  The adoption of ASC 815-19 did not have a material impact on the Partnership’s

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financial statements.  The disclosures required by ASC 815-19 are included in Note 4 to these financial statements.

In April 2009, the FASB issued ASC 820-10, Fair Value Measurements and Disclosures (FASB Staff Position No. 157-4, Determining Fair Value When the Volume and Level of Activity for the Asset or Liability Have Significantly Decreased and Identifying Transactions That Are Not Orderly).  ASC 820-10 provides additional guidance for estimating fair value in accordance with ASC 820-10, when the volume and level of activity for the asset or liability have significantly decreased as well as guidance on identifying circumstances that indicate a transaction is not orderly.  ASC 820-10 is effective for reporting periods ending after June 15, 2009.   The adoption of ASC 820-10 did not have a material impact on the Partnership’s financial statements.

In May 2009, the FASB issued ASC 855-10, Subsequent Events (Statement of Financial Accounting Standards No. 165, Subsequent Events), which establishes general standards of accounting for and disclosure of events that occur after the balance sheet date but before financial statements are issued or available to be issued. ASC 855-10 is effective for financial statements issued for fiscal years and interim periods ending after June 15, 2009.  The adoption of ASC 855-10 did not have a material impact on the Partnership’s financial statements.

In June 2009, the FASB issued ASC 105-10, Generally Accepted Accounting Principles, (Statement of Financial Accounting Standards No. 168, The FASB Accounting Standards Codification and the Hierarchy of Generally Accepted Accounting Principles—a replacement of FASB Statement No. 16). On the effective date of ASC 105-10, the ASC will supersede all then-existing non-SEC accounting and reporting standards. All other non-grandfathered, non-SEC accounting literature not included in the ASC will become non-authoritative. ASC 105-10 is effective for financial statements issued for interim and annual periods ending after September 15, 2009. The adoption of ASC 105-10 did not have a material impact on the Partnership’s financial statements.

6.   SUBSEQUENT EVENTS

The Partnership reviewed subsequent events occurring through November 16, 2009 the date that these financial statements were issued and determined that no subsequent events occurred that would require accrual or additional disclosure.

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Item 2.  Management’s Discussion and Analysis of Financial Condition and Results of Operations

MONTH-END NET ASSET VALUE PER SERIES F UNIT

Performance Summary  — Results of Trading

January 1, 2009 to September 30, 2009

January 1, 2009 to March 31, 2009

The Partnership posted a net loss for the quarter, with early gains offset by losses late in the quarter.  The stock indices sector was the only profitable sector for the quarter, with the largest losses occurring in the interest rate sector.

Stock indices trading contributed to gains early in the quarter through short exposures to global markets. Broad-based equity declines impacted global markets in January and February on negative economic news and poor earnings.  However, investors experienced a sharp reversal and rally in March as they began to perceive stabilization in the global financial system after several months of uncertainty. Within this environment, short global equity exposures to the US, Germany, Hong Kong and Japan, proved to be beneficial as markets substantially declined early in the period. However, many of these short equity exposures detracted late in the quarter as the markets rallied on positive corporate earnings and government stimulus efforts.

Trading in energies was relatively flat over the first three months of the year, with slight profits early in the quarter roughly balanced by later losses. Oil prices hit cyclical lows in February, falling below $40/barrel for the first time since 2004 before rebounding to nearly $50/barrel by the end of March on signs that economic deterioration appears to be slowing. Demand for energy continued to slump, weighed by a decrease in economic activity driven by the global recession.  Natural gas prices were negatively impacted by falling demand from power producers and their industrial clientele.

Short exposures in the metals sector detracted slightly from performance for the quarter, with gains early in the quarter outweighed by March losses. Prices for industrial metals such as copper, lead and zinc, rallied in March from their earlier lows on hopes that government stimulus efforts would spark industrial production and reduce existing basic materials inventory levels. Precious metals prices also rose during the quarter, continuing to benefit from higher levels of market volatility and economic uncertainty, as well as latent fears over growing inflation after the economy recovers.

Trading in agricultural commodities detracted from performance despite a profitable month of February. In particular, short positions in corn and soybeans profited in February on speculation that demand for biofuels and animal feed would decline in the midst of the recession, and demand for cotton process fell based on a reduced demand for raw materials. However, prices broadly recovered in March as investors perceived better economic times ahead.  Coffee prices improved substantially over the course of the quarter, as investors anticipated a reduced supply from Central and South America.

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Currency trading also detracted from performance for the quarter. Long exposures to Japanese yen and short exposures to the Euro contributed early in the quarter; however it was not enough to offset losses in the latter half of the quarter.  The foreign exchange markets were range-bound during February with declining volatility, resulting in a challenging environment for underlying managers with shorter holding periods. While demand for the U.S. dollar was strong early in the period due to high market uncertainty, late in the quarter, long U.S. dollar trades struggled following quantitative easing initiatives launched by the U.S. Federal Reserve.

The interest rate sector was the worst performing strategy for the quarter. Long U.S. treasury, Gilt, and German Bund exposures led losses, selling off despite a backdrop of stock market volatility, worsening economic conditions and regulatory uncertainty. March proved to be particularly challenging, with several government and central bank stimulus initiatives, including those by the U.S. Federal Reserve, the Bank of England, the Swiss National Bank and the Bank of Japan, creating a challenging environment for systematic managers.

April 1, 2009 to June 30, 2009

The Partnership posted a net loss for the quarter as mid-quarter gains were offset by losses early and late in the quarter. In general, Trading Advisors faced challenges as reduced volatility and shifting trends resulted in an environment with limited momentum to exploit. Overall, foreign exchange activity was the only positive contributor to gains in the currencies sector, with agriculture-based trades posting essentially flat returns. Amongst sectors producing losses for the quarter, the worst performer was interest rates, followed by energy, metals and stock indices.