YieldMax Launches Inverse MSTR ETF YieldMax introduced its 46th ETF, the YieldMax MSTR Short Option Income Strategy ETF (WNTR), on March 27, 2025. This ETF offers inverse exposure to MicroStrategy's stock, aiming to profit from declines while providing downside protection and monthly income. It employs synthetic covered put strategies and holds U.S. Treasuries as collateral.34