Company: PTY
Filing Date: 2025-06-06
Form Type: 424B5
Source: 0001193125-25-137029
Chunk: 277

Company: PIMCO CORPORATE & INCOME OPPORTUNITY FUND
Filing Date: 2025-06-06
Form: 424B5
Chunk 277
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 of purchase. Early repayment of principal on some mortgage-related securities (arising from prepayments of principal due to the sale of the underlying property, refinancing, or foreclosure, net of fees and costs that may be incurred) may expose the Fund to a lower rate of return upon reinvestment of principal. Also, if a security

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subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment. Like other fixed-income securities, when interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed-income securities. Adjustable rate mortgage-related and other ABS are also subject to interest rate risk. For example, because interest rates on most adjustable rate mortgage- and other ABS only reset periodically (e.g., monthly or quarterly), changes in prevailing interest rates (and particularly sudden and significant changes) can be expected to cause some fluctuations in the market value of these securities, including declines in value as interest rates rise. In addition, to the extent that unanticipated rates of pre-payment on underlying mortgages increase the effective duration of a mortgage-related security, the volatility of such security can be expected to increase. The residential mortgage market in the United States has experienced in the past, and could experience in the future, difficulties that may adversely affect the performance and market value of certain of the Fund’s mortgage-related investments. Delinquencies, defaults and losses on residential mortgage loans (especially subprime and second-lien mortgage loans) may increase substantially over a shorter period of time. A decline in or flattening of housing values may exacerbate such delinquencies and losses on residential mortgages. Borrowers with adjustable rate mortgage loans are more sensitive to changes in interest rates, which affect their monthly mortgage payments, and may be unable to secure replacement mortgages at comparably low interest rates. As a result of the 2008 financial crisis, a number of residential mortgage loan originators experienced serious financial difficulties or bankruptcy. Owing largely to the foregoing, reduced investor demand for mortgage loans and mortgage-related securities and increased investor yield requirements caused limited liquidity in the secondary market for certain mortgage-related securities, which adversely affected the market value of mortgage-related securities. It is possible that such limited liquidity in such secondary markets could recur or worsen in the future. Agency Mortgage-Related Securities. Payment of principal and interest on some mortgage pass-through securities (but not the market value of the securities