WASHINGTON — Coinbase said on 27 April it would fight the Securities and Exchange Commission over the agency's claim that much of its business is illegal and try to convince a court that Wall Street regulators lack the authority to oversee cryptocurrency markets.

The company outlined its legal strategy in a memorandum that formally responded to the SEC's earlier notice of a potential enforcement action against the company. The memo, made public by Coinbase along with a video featuring its chief executive, underscores the company's effort to generate political backing and public support for its confrontation with the SEC.