Strategy. The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in mortgage-backed securities of any maturity or type guaranteed by, or secured by collateral that is guaranteed by, the U.S. government, its agencies, instrumentalities or sponsored corporations (a Federal Agency), and in mortgage-backed securities privately issued in the United States, and in derivatives and other instruments that have economic characteristics similar to such securities. Mortgage-backed securities generally consist of government mortgage pass-through securities, collateralized mortgage obligations (CMOs), multiclass pass-through securities, private mortgage pass-through securities, stripped mortgage securities and inverse floaters. The Fund historically has invested primarily in mortgage-backed securities that directly or indirectly represent a participation in, or are secured by … Show more… The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in mortgage-backed securities of any maturity or type guaranteed by, or secured by collateral that is guaranteed by, the U.S. government, its agencies, instrumentalities or sponsored corporations (a Federal Agency), and in mortgage-backed securities privately issued in the United States, and in derivatives and other instruments that have economic characteristics similar to such securities. Mortgage-backed securities generally consist of government mortgage pass-through securities, collateralized mortgage obligations (CMOs), multiclass pass-through securities, private mortgage pass-through securities, stripped mortgage securities and inverse floaters. The Fund historically has invested primarily in mortgage-backed securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans secured by real property. Mortgage-backed securities also include mortgage pass-through certificates representing participation interests in pools of mortgage loans originated by the U.S. government or private lenders and guaranteed by U.S. government agencies such as the Government National Mortgage Association (GNMA), the Federal National Mortgage Association (FNMA) or the Federal Home Loan Mortgage Corporation (FHLMC). The Fund may invest in real estate mortgage investment conduits (REMICs). The Fund may invest in stripped mortgage securities, which are derivative multi-class mortgage securities. The Fund may also invest in asset-backed securities. The Fund may invest in illiquid or thinly traded securities. The Fund may also invest in securities that are subject to resale restrictions such as those contained in Rule 144A promulgated under the Securities Act of 1933. The Funds investments may include securities that do not produce immediate cash income, such as zero coupon securities and payment-in-kind securities. The Fund may purchase and sell securities on a when-issued and delayed delivery basis, which means that the Fund may buy or sell a security with payment and delivery taking place in the future. The Fund may also engage in to be announced (TBA) transactions, which are transactions in which a fund buys or sells mortgage-backed securities on a forward commitment basis. TBA transactions may be conducted as dollar rolls. The Fund may engage in short sales of TBA mortgages, including short sales of TBA mortgages the Fund does not own. The Fund can invest in derivative instruments including swap contracts, options and futures contracts. The Fund can use swap contracts, including interest rate swaps, to seek to hedge or adjust its exposure to interest rates. The Fund can also use swap contracts, including credit default swaps, to create long or short exposure to corporate or sovereign debt securities. The Fund can further use total return swaps to gain exposure to a reference asset, and volatility swaps to adjust the volatility profile of the Fund. The Fund can use options, including swaptions (options on swaps), to seek to manage interest rate risk and options on bond or rate futures to seek to manage interest rate exposure. The Fund can use futures contracts, including interest rate futures, to increase or reduce its exposure to interest rate changes. The Fund utilizes active duration (i.e., making investments to reduce or increase the sensitivity of the Funds portfolio to interest rate changes) and yield curve positioning (i.e., making investments that allow the Fund to benefit from varying interest rates) for risk management and for generating alpha (return on investments in excess of the Bloomberg U.S. Mortgage-Backed Securities Index). The portfolio managers utilize the Bloomberg U.S. Mortgage-Backed Securities Index as a reference in structuring the portfolio. The portfolio managers decide on appropriate risk factors such as duration, the shape of the U.S. Treasury yield curve, Federal Agency exposure, Federal Agency mortgage-backed security exposure and Treasury Inflation-Protected Security (TIPS) exposure relative to this index. The portfolio managers then employ proprietary technology to calculate appropriate position sizes for each of these risk factors. In doing so, the portfolio managers consider recommendations from a globally interconnected team of specialist decision makers in positioning the Fund to seek to generate alpha. The portfolio managers generally rely upon a team of market-specific specialists for trade execution and for assistance in determining efficient ways (in terms of cost-efficiency and selection) to implement those recommendations. Specialist investment professionals employ both top down and bottom-up analysis in determining whether to recommend larger or smaller exposure to specific risk factors. In general, these specialists will look for what they believe are attractive risk-reward opportunities and securities that best enable the Fund to pursue those opportunities. The portfolio managers consider the recommendations of these market-specific specialists in adjusting the Funds risk exposures and security selection on a real-time basis using proprietary communication technology. Although a variety of specialists provide input in the management of the Fund, the portfolio managers retain responsibility for ensuring the Fund is positioned appropriately in terms of risk exposures and position sizes. Decisions to purchase or sell securities are determined by the relative value considerations of the portfolio managers that factor in economic and credit-related fundamentals, market supply and demand, market dislocations and situation-specific opportunities. The purchase or sale of securities may be related to a decision to alter the Funds macro risk exposure (such as duration, yield curve positioning and sector exposure), a decision to limit or reduce the Funds exposure to a particular security or issuer, degradation of an issuers credit quality or general liquidity needs of the Fund. In attempting to meet its investment objective or to manage subscription and redemption requests, the Fund engages in active and frequent trading of portfolio securities. Show less