JPMorgan BetaBuilders U.S. Treasury Bond 1-3 Year ETF (BBSB) is an exchange-traded fund that seeks to provide current income by tracking the performance of the ICE U.S. Treasury 1-3 Year Bond Index through a representative sampling approach. The fund invests primarily in USD-denominated, fixed-rate U.S. Treasury securities publicly issued by the U.S. government with remaining maturities greater than one year and less than or equal to three years; it employs monthly index rebalancing and maintains a portfolio concentrated in short-term Treasuries, with 99.9% allocated to Treasuries and 0.1% to cash as of late 2025, alongside an average duration of 1.86 years and net expense ratio of 0.04%. Launched on April 19, 2023, as part of J.P. Morgan Asset Management's BetaBuilders suite—which includes companion ETFs for intermediate (BBIB) and long-term (BBLB) U.S. Treasury exposures—the fund operates under the J.P. Morgan Exchange-Traded Fund Trust and is managed by a team including Mark Willauer, Evan Olonoff, and Jan Ho. Headquartered in New York, the ETF targets investors seeking low-cost beta exposure to the short end of the U.S. Treasury yield curve, delivering monthly dividends and a Morningstar Gold Medalist rating as of September 2025. Recent developments include sustained net inflows of approximately $27.3 million over the past year through 2025, supporting assets under management reaching $32.03 million as of October 2025, alongside ongoing portfolio adjustments amid fluctuating yields, such as a 30-day SEC yield of 3.54% and 12-month rolling dividend yield of 3.98%; no major acquisitions, partnerships, or strategic shifts specific to BBSB have been reported in the last 1-2 years.