The U.K.'s Advertising Standards Authority (ASA) has issued an enforcement notice to over 50 companies that have advertised cryptocurrency services, advising them to review their ads to make sure they comply with new guidance.

• The advertising regulator told CoinDesk the list of 50 includes all firms that have previously been subject to ASA rulings. Among these companies are Coinbase (COIN), eToro, Luno and Crypto.com.

• "This is a ‘red alert’ priority issue for us and we’ve recently banned several crypto ads for misleading consumers and for being socially irresponsible," the ASA said.

• The new guidance requires advertisers to clearly state that crypto is unregulated in the U.K. and that the "value of investments are variable and can go down." Additionally, ads must not "state or imply that investment decisions are trivial, simple, easy or suitable for anyone" or "imply a sense of urgency to buy or create a fear of missing out, or that investments are ‘low risk’."

• Companies advertising crypto services have until May 2 to ensure their ads meet this guidance, after which non-compliant advertisers will be reported to the financial watchdog the Financial Conduct Authority (FCA).

• In January, the FCA announced its plans to tighten oversight of crypto advertising after it was granted additional powers by the government to regulate the industry.

• CoinDesk has contacted Coinbase, eToro, Luno and Crypto.com for comment on the new guidance, but had not received a response by press time. Luno, like CoinDesk, is owned by Digital Currency Group.

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