The SEC has not yet made any formal announcement about whether or not they are investigating Bitcoin, but many people believe that they are. The SEC is responsible for regulating the securities industry, and Bitcoin could be considered a security.
If the SEC is investigating Bitcoin, it is likely because they are concerned about potential fraud or manipulation.
Bitcoin is a decentralized digital currency that is not subject to any government regulation. This makes it attractive to criminals and those who want to avoid government scrutiny.
However, it also makes it very difficult for the SEC to track or regulate. If the SEC is investigating Bitcoin, they will likely be looking into ways to make it more difficult for criminals to use the currency and to protect investors from potential fraud.