Is dYdX legal in the US?

Could you please enlighten me on the legality of dYdX in the United States? I've been hearing quite a buzz about this cryptocurrency exchange platform, but I'm somewhat uncertain about its compliance with the regulatory framework in the country. Would you mind clarifying whether dYdX operates within the legal boundaries in the US? Is it registered and licensed by the appropriate authorities? Also, are there any specific regulations or restrictions that users in the US should be aware of when dealing with dYdX? Your insights would be greatly appreciated.