Commodity Exchange Traded Funds (ETFs) are essentially compliant products that package the business model of "holding commodities long-term and continuously generating rental income" and offer it to retail investors. Fund companies receive a share of the rental income earned by large investors who hold substantial amounts of commodities, lend related assets, and participate in derivatives market transactions, while also charging management fees. Fund companies are not simply optimistic about the market prospects of a particular commodity, but rather value its asset attribute of continuously generating "rent." Since May 13, 2016, the day BitMEX launched the world's first BTC perpetual contract, a funding rate mechanism has been implemented. From then on, long-term BTC holders could obtain rental income through hedging operations, marking its true transformation into a "rental asset." Before this, it existed merely as a speculative target for evangelistic beliefs; afterwards, it possessed a stable positive cash flow logic.