According to a blog post by two officials at the European Central Bank, the recent approval of spot bitcoin ETFs and resulting price rally do not prove that the cryptocurrency is a good investment. While bitcoin's price may increase in the short term, there is no "fair value" from which accurate predictions can be made. The officials also reiterated the ECB's longstanding position that bitcoin is a poor investment and a cumbersome means of payment. They cited ongoing market manipulation, demand for the currency in criminal activities, and shortcomings in regulatory measures as factors driving the current rally, but warned that authorities must remain vigilant to protect society when the market eventually collapses.