BlackRock MuniVest Fund, Inc. is a closed-end mutual fund, inaugurated by BlackRock, Inc., with its management entrusted to BlackRock Advisors, LLC. Domiciled in the United States, this fund primarily directs its investments toward the U.S. fixed income markets. A key focus is placed on long-term municipal bonds that possess an investment-grade rating and are exempt from federal income taxation. The fund specifically targets securities with maturities greater than a decade, having been established on September 29, 1988.