There are plenty of cryptocurrency-related products, services, and advice on the web that range from 'suspicious' to 'scam.' In an attempt to protect users from risk, Google is banning all online ads promoting cryptocurrencies and initial coin offerings starting in June.

Google announced that the restrictions would appear in its updated financial products policy, which will also see it ban ads for cryptocurrency wallets and trading advice. The restrictions cover online advertisements for other risky financial services, too, including binary options.

"We don't have a crystal ball to know where the future is going to go with cryptocurrencies, but we've seen enough consumer harm or potential for consumer harm that it's an area that we want to approach with extreme caution," Google's director of sustainable ads, Scott Spencer, told CNBC.

Google's decision comes after Facebook recently banned ads for financial products and services that are frequently associated with deceptive or misleading promotional practices. These include binary options, ICOs, and all cryptocurrencies.

The update means users won't see crypto-related ads on Google's services or sites that feature Google ads. Some businesses attempt to get around Facebook's rules by purposely misspelling words such as "bitcoin" in their ads, but Google said it would try to anticipate tricks like this.

The announcement also appeared within Google's "bad ads" report, in which the company said it removed 3.2 billion malicious, deceptive and controversial advertisements from the web in 2017---an increase from the 1.7 billion it scrubbed in 2016.

Initial coin offerings have come under increased scrutiny recently due to their high failure rate. According to tracker Tokendata (via, 46 percent of its 902 listed ICOs that took place last year have failed. If you include those that have "semi-failed" because the team has stopped all communications on social media, or because the project has no chance of success due to the community being so small, the figure rises to 59 percent. Yet these 531 failed or failing ICOs managed to raise $233 million between them.