iShares Short Duration High Yield Muni Active ETF (SHYM) seeks to maximize tax-free current income and secondarily capital appreciation through an actively managed portfolio principally composed of high-yield U.S. municipal bonds exempt from federal alternative minimum tax; short-duration bonds with maturities generally of five years or less and effective duration targeted below five years; up to 20% in distressed securities; and limited allocations to derivatives, cash equivalents, and other fixed-income instruments including asset-backed securities and corporates. The fund holds approximately 320 positions, with top issuers such as Public Finance Authority Wisconsin, New York Transportation Development Corp, Black Belt Energy Gas District, National Finance Authority NH, and University of Vermont & St Agricultural College. Issued by BlackRock ETF Trust II under the iShares brand and managed by BlackRock Fund Advisors with a net expense ratio of 0.35%, SHYM trades on Cboe BZX, distributes monthly dividends yielding around 4.5%, and operates in the U.S. fixed-income market targeting high-yield municipal segments for institutional and retail income-focused investors.
Launched on March 16, 2021, and headquartered with BlackRock in Wilmington, Delaware, the ETF manages approximately $370 million in assets. Recent developments include a merger with BlackRock High Yield Municipal Fund (MAYHX), adding $813 million in assets; a ticker change from HYMU to SHYM on February 10, 2025; rebranding from BlackRock to iShares branding on October 10, 2024; addition of "Short Duration" to the fund name on July 1, 2025, to reflect its duration strategy; introduction of a new customized benchmark in 2025 replacing a prior 80% high-yield muni blend; and portfolio manager addition of Patrick Haskell on February 10, 2025, alongside James Mauro, Kevin Maloney, Ryan McDonald, and Phillip Soccio.