The Internal Revenue Service has issued a new notice targeting Section 351 exchange ETFs, signaling increased scrutiny of structures that may violate the spirit of existing tax law. The guidance aims to address specific transactions within these funds that regulators believe circumvent intended tax provisions. Market participants are currently assessing the scope of the enforcement action, which appears focused on distinguishing between compliant exchanges and those exploiting regulatory loopholes. Industry experts suggest the notice serves as a clarification measure rather than a blanket prohibition, though the precise implications for existing and future crypto-related ETF structures remain under review.